机械专业外文翻译
机械专业外文文献翻译
翻译部分英文原文High-speed machining and demand for the development ofHigh-speed machining is contemporary advanced manufacturing technology an important component of the high-efficiency, High-precision and high surface quality, and other features. This article presents the technical definition of the current state of development of China's application fields and the demand situation.High-speed machining is oriented to the 21st century a new high-tech, high-efficiency, High-precision and high surface quality as a basic feature, in the automobile industry, aerospace, Die Manufacturing and instrumentation industries gained increasingly widespread application, and has made significant technical and economic benefits. contemporary advanced manufacturing technology an important component part.HSC is to achieve high efficiency of the core technology manufacturers, intensive processes and equipment packaged so that it has a high production efficiency. It can be said that the high-speed machining is an increase in the quantity of equipment significantly improve processing efficiency essential to the technology. High-speed machining is the major advantages : improve production efficiency, improve accuracy and reduce the processing of cutting resistance.The high-speed machining of meaning, at present there is no uniform understanding, there are generally several points as follows : high cutting speed. usually faster than that of their normal cutting 5 -10 times; machine tool spindle speed high, generally spindle speed in -20000r/min above 10,000 for high-speed cutting; Feed at high velocity, usually 15 -50m/min up to 90m/min; For different cutting materials and the wiring used the tool material, high-speed cutting the meaning is not necessarily the same; Cutting process, bladed through frequency (Tooth Passing Frequency) closer to the "machine-tool - Workpiece "system the dominant natural frequency (Dominant Natural Frequency), can be considered to be high-speed cutting. Visibility high-speed machining is a comprehensive concept.1992. Germany, the Darmstadt University of Technology, Professor H. Schulz in the 52th on the increase of high-speed cutting for the concept and the scope, as shown in Figure 1. Think different cutting targets, shown in the figure of the transition area (Transition), to be what is commonly called the high-speed cutting, This is also the time of metal cutting process related to the technical staff are looking forward to, or is expected to achieve the cutting speed.High-speed machining of machine tools, knives and cutting process, and other aspects specific requirements. Several were from the following aspects : high-speed machining technology development status and trends.At this stage, in order to achieve high-speed machining, general wiring with high flexibility of high-speed CNC machine tools, machining centers, By using a dedicated high-speed milling, drilling. These equipment in common is : We must also have high-speed and high-speed spindle system feeding system, Cutting can be achieved in high-speed process. High-speed cutting with the traditional cutting the biggest difference is that "Machine-tool-workpiece" the dynamic characteristics of cutting performance is stronger influence. In the system, the machine spindle stiffness, grip or form, a long knife set, spindle Broach, torque tool set, Performance high-speed impact are important factors.In the high-speed cutting, material removal rate (Metal Removal Rate, MRR), unit time that the material was removed volume, usually based on the "machine-tool-workpiece" whether Processing System "chatter." Therefore, in order to satisfy the high-speed machining needs, we must first improve the static and dynamic stiffness of machine spindle is particularly the stiffness characteristics. HSC reason at this stage to be successful, a very crucial factor is the dynamic characteristics of the master and processing capability.In order to better describe the machine spindle stiffness characteristics of the project presented new dimensionless parameter - DN value, used for the evaluation of the machine tool spindle structure on the high-speed machining of adaptability. DN value of the so-called "axis diameter per minute speed with the product." The newly developed spindle machining center DN values have been great over one million. To reduce the weight bearing, but also with an array of steel products than to the much more light ceramic ball bearings; Bearing Lubrication most impressive manner mixed with oil lubrication methods. In the field of high-speed machining. have air bearings and the development of magnetic bearings and magnetic bearings and air bearings combined constitute the magnetic gas / air mixing spindle.Feed the machine sector, high-speed machining used in the feed drive is usually larger lead, multiple high-speed ball screw and ball array of small-diameter silicon nitride (Si3N4) ceramic ball, to reduce its centrifugal and gyroscopic torque; By using hollow-cooling technology to reduce operating at high speed ball screw as temperature generated by the friction between the lead screw and thermal deformation.In recent years, the use of linear motor-driven high-speed system of up to'' Such feed system has removed the motor from workstations to Slide in the middle of all mechanical transmission links, Implementation of Machine Tool Feed System of zero transmission. Because no linear motor rotating components, from the role of centrifugal force, can greatly increase the feed rate. Linear Motor Another major advantage of the trip is unrestricted. The linear motor is a very time for a continuous machine shop in possession of the bed. Resurfacing of the very meeting where avery early stage movement can go, but the whole system of up to the stiffness without any influence. By using high-speed screw, or linear motor can greatly enhance machine system of up to the rapid response. The maximum acceleration linear motors up to 2-10G (G for the acceleration of gravity), the largest feed rate of up to 60 -200m/min or higher.2002 world-renowned Shanghai Pudong maglev train project of maglev track steel processing, Using the Shenyang Machine Tool Group Holdings Limited McNair friendship company production plants into extra-long high-speed system for large-scale processing centers achieve . The machine feeding system for the linear guide and rack gear drive, the largest table feed rate of 60 m / min, Quick trip of 100 m / min, 2 g acceleration, maximum speed spindle 20000 r / min, the main motor power 80 kW. X-axis distance of up to 30 m, 25 m cutting long maglev track steel error is less than 0.15 mm. Maglev trains for the smooth completion of the project provided a strong guarantee for technologyIn addition, the campaign machine performance will also directly affect the processing efficiency and accuracy of processing. Mold and the free surface of high-speed machining, the main wiring with small cut deep into methods for processing. Machine requirements in the feed rate conditions, should have high-precision positioning functions andhigh-precision interpolation function, especially high-precision arc interpolation. Arc processing is to adopt legislation or thread milling cutter mold or machining parts, the essential processing methods. Cutting Tools Tool Material developmenthigh-speed cutting and technological development of the history, tool material is continuous progress of history. The representation ofhigh-speed cutting tool material is cubic boron nitride (CBN). Face Milling Cutter use of CBN, its cutting speed can be as high as 5000 m / min, mainly for the gray cast iron machining. Polycrystalline diamond (PCD) has been described as a tool of the 21st century tool, It is particularly applicable to the cutting aluminum alloy containing silica material, which is light weight metal materials, high strength, widely used in the automobile, motorcycle engine, electronic devices shell, the base, and so on. At present, the use of polycrystalline diamond cutter Face Milling alloy, 5000m/min the cutting speed has reached a practical level. In addition ceramic tool also applies to gray iron of high-speed machining; Tool Coating : CBN and diamond cutter, despite good high-speed performance, but the cost is relatively high. Using the coating technology to make cutting tool is the low price, with excellent mechanical properties, which can effectively reduce the cost. Now high-speed processing of milling cutter, with most of the wiring between the Ti-A1-N composite technology for the way of multi-processing, If present in the non-ferrous metal or alloy material dry cutting, DLC (Diamond Like Carbon) coating on thecutter was of great concern. It is expected that the market outlook is very significant;Tool clamping system : Tool clamping system to support high-speed cutting is an important technology, Currently the most widely used is a two-faced tool clamping system. Has been formally invested as a commodity market at the same clamping tool system are : HSK, KM, Bigplus. NC5, AHO systems. In the high-speed machining, tool and fixture rotary performance of the balance not only affects the precision machining and tool life. it will also affect the life of machine tools. So, the choice of tool system, it should be a balanced selection of good products.Process ParametersCutting speed of high-speed processing of conventional shear velocity of about 10 times. For every tooth cutter feed rate remained basically unchanged, to guarantee parts machining precision, surface quality and durability of the tool, Feed volume will also be a corresponding increase about 10 times, reaching 60 m / min, Some even as high as 120 m / min. Therefore, high-speed machining is usually preclude the use of high-speed, feed and depth of cut small cutting parameters. Due to the high-speed machining cutting cushion tend to be small, the formation of very thin chip light, Cutting put the heat away quickly; If the wiring using a new thermal stability better tool materials and coatings, Using the dry cutting process for high-speed machining is the ideal technology program. High-speed machining field of applicationFlexible efficient production lineTo adapt to the needs of new models, auto body panel molds andresin-prevention block the forming die. must shorten the production cycle and reduce the cost of production and, therefore, we must make great efforts to promote the production of high-speed die in the process. SAIC affiliated with the company that : Compared to the past, finishing, further precision; the same time, the surface roughness must be met, the bending of precision, this should be subject to appropriate intensive manual processing. Due to the extremely high cutting speed, and the last finishing processes, the processing cycle should be greatly reduced. To play for machining centers and boring and milling machining center category represented by the high-speed machining technology and automatic tool change function of distinctions Potential to improve processing efficiency, the processing of complex parts used to be concentrated as much as possible the wiring process, that is a fixture in achieving multiple processes centralized processing and dilute the traditional cars, milling, boring, Thread processing different cutting the limits of technology, equipment and give full play to the high-speed cutting tool function, NC is currently raising machine efficiency and speed up product development in an effective way. Therefore, the proposed multi-purpose tool of the new requirements call for a tool to complete different partsof the machining processes, ATC reduce the number of ATC to save time, to reduce the quantity and tool inventory, and management to reduce production costs. More commonly used in a multifunctional Tool, milling, boring and milling, drilling milling, drilling-milling thread-range tool. At the same time, mass production line, against the use of technology requires the development of special tools, tool or a smart composite tool, improve processing efficiency and accuracy and reduced investment. In the high-speed cutting conditions, and some special tools can be part of the processing time to the original 1 / 10 below, results are quite remarkable. HSC has a lot of advantages such as : a large number of materials required resection of the workpiece with ultrafine, thin structure of the workpiece, Traditionally, the need to spend very long hours for processing mobile workpiece and the design of rapid change, short product life cycle of the workpiece, able to demonstrate high-speed cutting brought advantages.中文译文高速切削加工的发展及需求高速切削加工是当代先进制造技术的重要组成部分，拥有高效率、高精度及高表面质量等特征。
机械学英语
机械学英语
机械学（Mechanical Engineering）涉及广泛的工程领域，涵盖机械设计、制造、材料、热力学、控制等多个方面。
以下是一些常见的机械学英语术语及其解释：
1. Mechanical Engineering - 机械工程
2. Thermodynamics - 热力学
3. Fluid Mechanics - 流体力学
4. Mechanics - 力学
5. Materials Science - 材料科学
6. Manufacturing Processes - 制造工艺
7. Control Systems - 控制系统
8. Robotics - 机器人技术
9. Kinematics - 运动学
10. Dynamics - 动力学
11. Statics - 静力学
12. Heat Transfer - 热传导
13. Machine Design - 机械设计
14. CAD/CAM - 计算机辅助设计/计算机辅助制造
15. Vibration Analysis - 振动分析
16. Finite Element Analysis (FEA) - 有限元分析
17. Hydraulics - 液压学
18. Pneumatics - 气动学
19. Turbomachinery - 涡轮机械
20. Engineering Drawing - 工程制图
这些术语是在机械工程领域中常见的英语专业术语，涵盖了机械工程学科的各个方面。
深入学习这些术语可以帮助理解和掌握机械工程相关的知识和技术。
机械专业毕业设计外文翻译10
翻译部分英文部分ADV ANCED MACHINING PROCESSESAs the hardware of an advanced technology becomes more complex, new and visionary approaches to the processing of materials into useful products come into common use. This has been the trend in machining processes in recent years.. Advanced methods of machine control as well as completely different methods of shaping materials have permitted the mechanical designer to proceed in directions that would have been totally impossible only a few years ago.Parallel development in other technologies such as electronics and computers have made available to the machine tool designer methods and processes that can permit a machine tool to far exceed the capabilities of the most experienced machinist.In this section we will look at CNC machining using chip-making cutting tools. CNC controllers are used to drive and control a great variety of machines and mechanisms, Some examples would be routers in wood working; lasers, plasma-arc, flame cutting, and waterjets for cutting of steel plate; and controlling of robots in manufacturing and assembly. This section is only an overview and cannot take the place of a programming manual for a specific machine tool. Because of the tremendous growth in numbers and capability of comp uters ,changes in machine controls are rapidly and constantly taking place. The exciting part of this evolution in machine controls is that programming becomeseasier with each new advanced in this technology.Advantages of Numerical ControlA manually operated machine tool may have the same physical characteristics as a CNC machine, such as size and horsepower. The principles of metal removal are the same. The big gain comes from the computer controlling the machining axes movements. CNC-controlled machine tools can be as simple as a 2-axis drilling machining center (Figure O-1). With a dual spindle machining center, the low RPM, high horsepower spindle gives high metal removal rates. The high RPM spindle allows the efficient use of high cutting speed tools such as diamonds and small diameter cutters (Figure O-2). The cutting tools that remove materials are standard tools such as milling cutters, drills, boring tools, or lathe tools depending on the type of machine used. Cutting speeds and feeds need to be correct as in any other machining operation. The greatest advantage in CNC machining comes from the unerring and rapid positioning movements possible. A CNC machine does dot stop at the end of a cut to plan its next move; it does not get fatigued; it is capable of uninterrupted machining error free, hour after hour. A machine tool is productive only while it is making chips.Since the chip-making process is controlled by the proper feeds and speeds, time savings can be achieved by faster rapid feed rates. Rapid feeds have increased from 60 to 200 to 400 and are now often approaching 1000 inches per minute (IPM). These high feed rates can pose a safety hazard to anyone within the working envelope of the machine tool.Complex contoured shapes were extremely difficult to product prior to CNC machining .CNC has made the machining of these shapes economically feasible. Design changes on a part are relatively easy to make by changing the program that directs the machine tool.A CNC machine produces parts with high dimensional accuracy and close tolerances without taking extra time or special precautions, CNC machines generally need less complex work-holding fixtures, which saves time by getting the parts machined sooner. Once a program is ready and production parts, each part will take exactly the same amount of time as the previous one. This repeatability allows for a very precise control of production costs. Another advantage of CNC machining is the elimination of large inventories; parts can be machined as needs .In conventional production often a great number of parts must be made at the same time to be cost effective. With CNC even one piece can be machined economically .In many instances, a CNC machine can perform in one setup the same operations that would require several conventional machines.With modern CNC machine tools a trained machinist can program and product even a single part economically .CNC machine tools are used in small and large machining facilities and range in size from tabletop models to huge machining centers. In a facility with many CNC tools, programming is usually done by CNC programmers away from the CNC tools. The machine control unit (MCU) on the machine is then used mostly for small program changes or corrections. Manufacturing with CNC tools usually requires three categories of persons. The first is the programmer, who is responsible for developing machine-ready code. The next person involved is the setup person, who loads the raw stork into the MCU, checks that the co rrect tools are loaded, and makes the first part. The third person is the machine and unloads the finished parts. In a small company, one person is expected to perform all three of these tasks.CNC controls are generally divided into two basic categories. One uses a ward address format with coded inputs such as G and M codes. The other users a conversational input; conversational input is also called user-friendly or prompted input. Later in this section examples of each of these programming formats in machining applications will be describes.CAM and CNCCAM systems have changed the job of the CNC programmer from one manually producing CNC code to one maximizing the output of CNC machines. Since CNC machine tools are made by a great number of manufacturers, many different CNC control units are in use. Control units from different manufacturers use a variety of program formats and codes. Many CNC code words are identical for different controllers, but a great number vary from one to another.To produce an identical part on CNC machine tools with different controllers such as one by FANCU, OKUMA or DYNAPATH, would require completely different CNC codes. Each manufacturer is constantly improving and updating its CNC controllers. These improvements often include additional code words plus changes in how the existing code works.A CAM systems allows the CNC programmer to concentrate on the creation of an efficient machining process, rather then relearning changed code formats. A CNC programmer looks atthe print of a part and then plans the sequence of machining operations necessary to make it (Figure O-3). This plan includes everything, from the selection of possible CNC machine tools, to which tooling to use, to how the part is held while machining takes place. The CNC programmer has to have a thorough understanding of all the capacities and limitations of the CNC machine tools that a program is to be made for. Machine specifications such as horsepower, maximum spindle speeds, workpiece weight and size limitations, and tool changer capacity are just some of the considerations that affect programming.Another area of major importance to the programmer is the knowledge of machining processes. An example would be the selection of the surface finish requirement specified in the part print. The sequence of machining processes is critical to obtain acceptable results. Cutting tool limitations have to be considered and this requires knowledge of cutting tool materials, tool types, and application recommendations.A good programmer will spend a considerable amount of time in researching the rapidly growing volume of new and improved tools and tool materials. Often the tool that was on the cutting edge of technology just two years ago is now obsolete. Information on new tools can come from catalogs or tool manufacturers' tooling engineers. Help in tool selection or optimum tool working conditions can also be obtained from tool manufacturer software. Examples would be Kennametal's "TOOLPRO", software designed to help select the best tool grade, speed, and feed rates for different work materials in turning application. Another very important feature of "TOOLPRO" is the display of the horsepower requirement for each machining selection. This allow the programmer to select a combination of cutting speed, feed rate, and depth of cut that equals the machine's maximum horsepower for roughing cuts. For a finishing cut, the smallest diameter of the part being machined is selected and then the cutting speed varied until the RPM is equal to the maximum RPM of the machine. This helps in maximizing machining efficiency. Knowing the horsepower requirement for a cut is critical if more than one tool is cutting at the same time.Software for a machining center application would be Ingersoll Tool Company's "Actual Chip Thickness", a program used to calculate the chip thickness in relation to feed-per-tooth for a milling cutter, especially during a shallow finishing cut. Ingersoll's "Rigidity Analysis" software ealculates tool deflection for end mills as a function of tool stiffness and tool force.To this point we looked at some general qualifications that a programmer should possess. Now we examine how a CAM system works. Point Control Company's SmartCam system uses the following approach. First, the programmer makes a mental model of the part to be machined. This includes the kind of machining to be performed-turning or milling. Then the part print is studied to develop a machining sequence, roughing and finishing cuts, drilling, tapping, and boring operations. What work-holding device is to be used, a vise or fixture or clamps? After these considerations, computer input can be started. First comes the creation of a JOBPLAN. This JOBPLAN consists of entries such as inch or metric units, machine type, part ID, type of workpiece material, setup notes, and a description of the required tools.This line of information describes the tool by number, type, and size and includes theappropriate cutting speed and feed rate. After all the selected tools are entered, the file is saved.The second programming step is the making of the part. This represents a graphic modeling of the projected machining operation. After selecting a tool from the prepared JOBPLAN, parameters for the cutting operation are entered. For a drill, once the coordinate location of the hole and the depth are given, a circle appears on that spot. If the location is incorrect, the UNDO command erases this entry and allows you to give new values for this operation. When an end mill is being used, cutting movements (toolpath) are usually defined as lines and arcs. As a line is programmed, the toolpath is graphically displayed and errors can be corrected instantly.At any time during programming, the command SHOWPATH will show the actual toolpath for each of the programmed tools. The tools will be displayed in the sequence in which they will be used during actual machining. If the sequence of a tool movement needs to be changed, a few keystrokes will to that.Sometimes in CAM the programming sequence is different from the actual machining order. An example would be the machining of a pocket in a part. With CAM, the finished pocket outline is programmed first, then this outline is used to define the ro ughing cuts to machine the pocket. The roughing cuts are computer generated from inputs such as depth and width of cut and how much material to leave for the finish cut. Different roughing patterns can be tried out to allow the programmer to select the most efllcient one for the actual machining cuts. Since each tool is represented by a different color, it is easy to observe the toolpath made by each one.A CAM system lets the programmer view the graphics model from varying angles, such as a top, front, side, or isometric view. A toolpath that looks correct from a top view, may show from a front view that the depth of the cutting tool is incorrect. Changes can easily be made and seen immediately.When the toolpath and the sequence of operations are satisfactory, machine ready code has to be made. This is as easy as specifying the CNC machine that is to be used to machine the part. The code generator for that specific CNC machin e during processing accesses four different files. The JOBPLAN file for the tool information and the GRAPHICE file for the toolpath and cutting sequence. It also uses the MACHINE DEFINE file which defines the CNC code words for that specific machine. This file also supplies data for maximum feed rates, RPM, toolchange times, and so on. The fourth file taking part in the code generating process is the TEMPLATE file. This file acts like a ruler that produces the CNC code with all of its parts in the right place and sequence. When the code generation is complete, a projected machining time is displayed. This time is calculated from values such as feed rates and distances traveled, noncutting movements at maximum feed rates between points, tool change times, and so on. The projected machining time can be revised by changing tooling to allow for higher metal removal rates or creating a more efficient toolpath. This display of total time required can also be used to estimate production costs. If more then one CNC machine tool is available to machine this part, making code and comparing the machining time may show that one machine is more efficient than the others.CAD/CAMAnother method of creating toolpath is with the use of a Computer-aided Drafting (CAD) file. Most machine drawings are created using computers with the description and part geometry stored in the computer database. SmartCAM, though its CAM CONNECTION, will read a CAD file and transfer its geometry represents the part profile, holes, and so on. The programmer still needs to prepare a JOBPLAN with all the necessary tools, but instead of programming a profile line by line, now only a tool has to be assigned to an existing profile. Again, using the SHOWPA TH function will display the toolpath for each tool and their sequence. Constant research and developments in CAD/CAM interaction will change how they work with each other. Some CAD and CAM programs, if loaded on the same computer, make it possible to switch between the two with a few keystrokes, designing and programming at the same time.The work area around the machine needs to be kept clean and clear of obstructions to prevent slipping or tripping. Machine surfaces should not be used as worktables. Use proper lifting methods to handle heavy workpieces, fixtures, or heavy cutting tools. Make measurements only when the spindle has come to a complete standstill. Chips should never be handled with bare hands.Before starting the machine make sure that the work-holding device and the workpiece are securely fastened. When changing cutting tools, protect the workpiece being machined from damage, and protect your hands from sharp cutting edges. Use only sharp cutting tools. Check that cutting tools are installed correctly and securely.Do not operate any machine controls unless you understand their function and what the y will do.The Early Development Of Numerically Controlled Machine ToolsThe highly sophisticated CNC machine tools of today, in the vast and diverse range found throughout the field of manufacturing processing, started from very humble beginnings in a number of the major industrialized countries. Some of the earliest research and development work in this field was completed in USA and a mention will be made of the UK's contribution to this numerical control development.A major problem occurred just after the Second World War, in that progress in all areas of military and commercial development had been so rapid that the levels of automation and accuracy required by the modern industrialized world could not be attained from the lab our intensive machines in use at that time. The question was how to overcome the disadvantages of conventional plant and current manning levels. It is generally ackonwledged that the earliest work into numerical control was the study commissioned in 1947 by the US governme nt. The study's conclusion was that the metal cutting industry throughout the entire country could not copy with the demands of the American Air Force, let alone the rest of industry! As a direct result of the survey, the US Air Force contracted the Persons Corporation to see if they could develop a flexible, dynamic, manufacturing system which would maximize productivity. TheMassachusetts Institute of Technology (MIT) was sub-contracted into this research and development by the Parsons Corporation, during the period 1949-1951,and jointly they developed the first control system which could be adapted to a wide range of machine tools. The Cincinnati Machine Tool Company converted one of their standard 28 inch "Hydro-Tel" milling machines or a three-axis automatic milling made use of a servo-mechanism for the drive system on the axes. This machine made use of a servomechanism for the drive system on the axes, which controlled the table positioning, cross-slide and spindle head. The machine cab be classified as the first truly three axis continuous path machine tool and it was able to generate a required shape, or curve, by simultaneous slide way motions, if necessary.At about the same times as these American advances in machine tool control were taking Place, Alfred Herbert Limited in the United Kingdom had their first Mutinous path control system which became available in 1956.Over the next few years in both the USA and Europe, further development work occurred. These early numerical control developments were principally for the aerospace industry, where it was necessary to cut complex geometric shapes such as airframe components and turbine blades. In parallel with this development of sophisticated control systems for aerospace requirements, a point-to-point controller was developed for more general machining applications. These less sophisticated point-to-point machines were considerably cheaper than their more complex continuous path cousins and were used when only positional accuracy was necessary. As an example of point-to-point motion on a machine tool for drilling operations, the typical movement might be fast traverse of the work piece under the drill's position-after drilling the hole, anther rapid move takes place to the next hole's position-after retraction of the drill. Of course, the rapid motion of the slideways could be achieved by each axis in a sequential and independent manner, or simultaneously. If a separate control was utilisec for each axis, the former method of table travel was less esse ntial to avoid any backlash in the system to obtain the required degree of positional accuracy and so it was necessary that the approach direction to the next point was always the same.The earliest examples of these cheaper point-to-point machines usually did not use recalculating ball screws; this meant that the motions would be sluggish, and sliderways would inevitably suffer from backlash, but more will be said about this topic later in the chapter.The early NC machines were, in the main, based upon a modified milling machine with this concept of control being utilized on turning, punching, grinding and a whole host of other machine tools later. Towards the end of the 1950s,hydrostatic slideways were often incorporated for machine tools of highly precision, which to sonic extent overcame the section problem associated with conventional slideway response, whiles averaging-out slideway inaccuracy brought about a much increased preasion in the machine tool and improved their control characteristics allows "concept of the machining center" was the product of this early work, as it allowed the machine to manufacture a range of components using a wide variety of machining processes at a single set-up, without transfer of workpieces to other variety machine tools. A machining center differed conceptually in its design from that of a milling machine, In that thecutting tools could be changed automatically by the transfer machanism, or selector, from the magazine to spindle, or vice versa.In this ductively and the automatic tool changing feature enabled the machining center to productively and efficiently machine a range of components, by replacing old tools for new, or reselecting the next cutter whilst the current machining process is in cycle.In the mid 1960s,a UK company, Molins, introduced their unique "System 24" which was meant represent the ability of a system to machine for 24 hours per day. It could be thought of as a "machining complex" which allowed a series of NC single purpose machine tools to be linked by a computerized conveyor system. This conveyor allowed the work pieces to be palletized and then directed to as machine tool as necessary. This was an early, but admirable, attempt at a form of Flexible manufacturing System concept, but was unfortunately doomed to failure. Its principal weakness was that only a small proportion of component varieties could be machine at any instant and that even fewer work pieces required the same operations to be performed on them. These factors meant that the utilization level was low, coupled to the fact that the machine tools were expensive and allowed frequent production bottlenecks of work-in-progress to arise, which further slowed down the whole operation.The early to mid-1970s was a time of revolutionary in the area of machine tool controller development, when the term computerized numerical control (CNC) became a reality. This new breed of controllers gave a company the ability to change work piece geometries, together with programs, easily with the minimum of development and lead time, allowing it to be economically viable to machine small batches, or even one-off successfully. The dream of allowing a computerized numerical controller the flexibility and ease of program editing in a production environment became a reality when two ralated factors occurred.These were:the development of integrated circuits, which reduces electronics circuit size, giving better maintenance and allowing more standardization of desing; that general purpose computers were reduced in size coupled to the fact that their cost of production had fallen considerably.The multipie benefits of cheaper electorics with greater reliability have result in the CNC fitted to the machine tools today, with the power and sophistication progtessing considerably in the last few years, allowing an almost artificial intelligence(AI) to the latest systems. Over the years, the machine tools builders have produced a large diversity in the range of applications of CNC and just some of those development will be reviewed in V olume Ⅲ。
机械制造专业外文翻译-轴、联轴器和滚动轴承
外文原文：shafts、couplings and rolling contact bearingskey words: shafts、couplings、bearingsVirtually all machines contain shafts.The most common shape for shafts is circular and the cross section can be either solid or hollow (hollow shafts can result in weight savings ).Rectangular shafts are sometimes used ,as in screwdriver blades,socket wrenches and control knob stems .A shaft must have adequate torsional strength to transmit torque and not be overstressed. It also be torsionally stiff enough so that one mounted component does not deviate excessively from its original angular position relative to a second component mounted on the same shaft. Generally speaking ,the angle of twist should not exceed one degree in a shaft length equal to 20 diameters.Shafts are mounted inbearings and transmint power through such devices as gears, pullerys, cams and clutches. These devices introduce forces which attempt to bend the shaft; hence, the shaft must be rigid enough to prevent overloading of the supporting bearings. In general, the bending deflection of a shaft should not exceed 0.01 in. per ft of length between bearing supports.In addition, the shaft must be able to sustain a combination of bending and torsional loads. Thus an equivalent load must be consideredwhich takes into account both torsion and bending. Also, the allowable stress must contain a factor of safety which includes fatigue, since torsional and bending stress reversals occur.For diameters less than 3 in. , the usual shaft material is cold-rolled ateel containing about 0.4 percent carbon. Shafts are either cold-rolled or forged in sizes from 3 in. to 5 in. ,shafts are forged and machined to size .Pleastic shafts are widely used for light load applications. One advantage of using plastic is safety in electrical applications ,since plastic is a poor conductor of electricity.Components such as gears and pulleys are mounted on shafts by means of key .The design of the key and the corresponding keyway in the shaft must be prperly evaluated. For example ,stress concentrations occur in shafts due to keyways ,and the material removed to form the keyway further weakens the shaft.If shafts are run at cirtical speeds ,severe vibrations can occur which can seriously damage a machine. It is important to know the magnitude of these critical speeds so that they can be avoided. As a general rule of thumb,the difference between the operating speed and the critical speed should be at least 20 percent .Another important aspect of shaft design is the method of directly connecting one shaft to another. This is accomplished by devices such as rigid and flexible couplings.A coupling is a device for connecting the eds of adjacent shafts. In machine construction, ouplings are used to effect a semipermanent connection between adjacent rotating shafts. The connection is permanent in the sense that it is not meant to be broken during the useful life of the machine, but it can be broken and restored in an emergency or when worn parts are replaced.There are several types of shaft couplings, their characteristics depend on the purpose for which they are used. If an exceptionally long shaft is required in a manufacturing plant or a propeller shaft on a ship, it is made in sections that are coupled together with rigid couplings. A common type of rigid coupling consists of two mating radial flanges(disks) that are cttached by key-driven hubs to the eds of adjacent shaft sections and bolted together through the flanges to form a rigid connection. Alignment of the connected shafts is usually effeted by means of a rabbet joint on the face of the flanges.In connecting shafts belonging to separate devices (such as an electric motor and a gearbox ),precise aligning of the shafts is difficult and a flexible coupling is used. This coupling connects theshafts in such a way as to minimize the harmful effects of shaft misalignment. Flexible couplings also permit the shafts to deflect under their separate systems of with one another. Flexible couplings can also serve to reduce the intensity of shock loads and vibrations transmitted from one shaft to another.Virtually all shafts contain rolling contact bearings.The concern of a machine designer with ball and roller bearings is fivefold as follows:(a) life in relation to load; (b) stiffness ,i.e. deflections under load; (c) friction;(d) wear; (e) noise. For moderate loads and speeds the correct selection of a standard bearing on the basis of load rating will usually secure satisfactory performance. The deflection of the bearing elements will become important where loads are high, although this is usuallyof less magnitude than that of the shafts or other components associated with the bearing. Where speeds are high special cooling arrangements become necessary which may increase frictional drag. Wear is primarily associated with the introduction of contaminants, and sealing arrangements must be chosen with regard the hostility of the environment.Because the high quality and low price of ball and roller bearings depends on quantity production, the task of the machine designer becomes one of selection rather than design. Rolling-contact bearings are generally made with ateel which is through-hardened toabout 900HV,although in many mechanisms special races are not provided and the interacting surfaces are hardened to about 600 HV. It is not surprising that, owing to the high stresses involved, a predominant form of failure should be metal fatigue, and a good deal of work is currently in progress intended to improve the reliability of this type of bearing. Design can bebased on accepted values of life and it is generral practice in the bearing industry to define the load capacity of the bearing as that value below which 90 lpercent of a batch will exceed a lift of ane million revolutions.Notwithstanding the fact that responsibility for the basic design of ball and roller bearings rests with the bearing manufacturer, the machine designer must form a correct appreciation of the duty to be performed by the bearing and be concerned not only with bearing selection but with the conditions for correct installation.The fit of the bearing races onto the shaft or onto the housings is of critical importance because of their combined effect on the internal clearance of the bearing as well as preserving the desired degree of interference fit. Inadequate interference can induce serious trouble from fretting corrosion. The inner race is frequently located axially by abutting against a shoulder. A radius at this point is essential for the avoidance of stress concentration and ball races are provides with a radius or chamfer to allow space for this .Where life is not the determining factor in design, it is usual to determine maximum loading by the amount towhich a bearing will deflect under load. Thus the concept of “static load-carrying capacity” is understood to mean the load that can be alpplied to a bearing, which is either stationary or subject to slight swiveling motions, without impairing its running qualities for subsequent rotational motion. This has beendetermined by practical experience as the load which when applied to a bearing results in a total deformation of the rolling element and raceway at any point of contact not exceeding 0.01 percent of the rolling-element diameter. This would correspond to a permanent deformation of 0.00025 mm for a ball 25mm in diameter.The successful functioning of many bearing depends upon providing them with adequate protection against their environment, and in some circumstances the enviroration of the bering surfaces. Achievement of the correct functioning of seals is an essential part of bearing design. Moreover, seals which are applied to moving parts for any purpose are of interest to tribologists because they are components of bearing systems and can only be designed satisfactorily on the basis of the approlpriate bearing theory. Notwithstanding their importance, the amount of research effort that has been devoted to the understanding of the understanding of the behavior of seals has been small when compared with that devoted to other aspects of bearing technology.References:1 Erickson.Belt and Application for Engineers.Marcel Dekker.Inc,19972 South,Mancuso.Mechanical Power Transmission Components.1994中文译文：轴、联轴器和滚动轴承关键词：轴、联轴器、轴承实际上，几乎所有的机器中都装有轴。
机械制造及自动化专业外文翻译--运动的综合,凸轮和齿轮
外文原文：Kinematic Synthesis ，Cams and Gears Mechanisms form the basic geometrical elements of many mechanical devices including automatic packaging machinery, typewriters, mechanical toys, textile machinery, and others. A mechanism typically is designed to create a desired motion of a rigid body relative to a reference member. Kinematic design, or kinematic syntheses, of mechanisms often is the first step in the design of a complete machine. When forces are considered, the additional problems of dynamics, bearing loads, stresses, lubrication, and the like are introduced, and the larger problem becomes one of machine design.A kinematician defined kinematics as “the study of the motion of mechanisms and methods of creating them.” The first part of this definition deals with kinematic analysis. Given a certain mechanism, the motion characteristics of its components will be determined by kinematic analysis. The statement of the tasks of analysis contains all principal dimensions of the mechanism, the interconnections of its links, and the specification of the input motion or method of actuation. The objective is to find the displacements, velocities, accelerations, shock or jerk (second acceleration) , and perhaps higher accelerations of the various members, as well as the paths described and motions performed by certain elements. In short, in kinematic analysis we determine the performance of a given mechanism. The second part of definition may be paraphrased in two ways:1. The study of methods of creating a given motion by means of mechanisms.2. The study of methods of creating mechanisms having a given motion.In either version, the motion is given and the mechanism is to be found. This is the essence of kinematic synthesis. Thus kinematic synthesis deals with the systematic design of mechanisms for a given performance. The area of synthesis may be grouped into two categories.1. Type synthesis. Given the required performance, what type of mechanism will be suitable? (Gear trains? Linkages? Cam mechanisms? ) Also, how many links should the mechanism have? How many degrees of freedom are required? What configuration id desirable? And so on. Deliberations involving the number of links and degrees of freedom are often referred to as the province of a subcategory of type synthesis called number synthesis.2. Dimensional synthesis. The second major category of kinematic synthesis is best defined by way of its objective: Dimensional synthesis seeks to determine the significant dimensions and the starting position of a mechanism of preconceived type for a specified task and prescribed performance.Significant dimensions mean link lengths or distances on binary, ternary, and so on, links, angles between axis, cam-contour dimensions and cam-follower diameters, eccentricities, gear rations, and so forth. A mechanism of preconceived type may be a slider-crank linkage, a four-bar linkage, a cam with flat follower, or a more complex linkage of a certain configuration defined topologically but not dimensionally. Thereare three customary tasks for kinematic synthesis: function generation, path generation and motion generation.In function generation mechanisms rotation or sliding motions of input and output links must be correlated. For an arbitrary function )(x f y =, a kinematic synthesis task may be to design a linkage to correlate input and output such that the input moves by x , the output moves by )(x f y = for the range 10+<<n x x x . In the case of rotary input and output, the angles of rotation ϕ and ψ are the linear analogs of x and y respectively. When the input link is rotated to a value of the independent x , the mechanism in a “black box” causes the output link to turn to the corresponding value of the dependent variable )(x f y =. This may be regarded as a simple case of a mechanical analog computer. A variety of different mechanisms cou ld be contained within the “black box”. However, the four -bar linkage is not capable of error-free generation of an arbitrary function and can match the function at only a limited number of precision points. It is widely used in industry because the four-bar linkage id simple to construct and maintain.In path generation mechanism a point on a “floating link” is to trace a path defined with respect to a fixed frame of reference. If the path points are to be correlated with either time or input-link positions, the task is called path generation with prescribed timing. An example of path generation mechanisms id a four-bar linkage designed to pitch a baseball or tennis ball. In this case the trajectory of point p would be such as to pick up a ball at a prescribed location and to deliver the ball along a prescribed path with prescribed timing for reaching a suitable throw-velocity and direction.There are many situations in the design of mechanical devises in which it is necessary either to guide a rigid body through a series of specified, finitely separated positions or to impose constraints on the velocity and/or acceleration of the moving body at a reduced number of finitely separated positions. Motion-generation or rigid-body guidance mechanism requires that an entire body be guided through a prescribed motion sequence. The body to be guided usually is a part of a floating link, of which not only is the path of a point p prescribed, but also the rotation of a line passing through the point and embedded in the body,. For instance, the line might represent a carrier link in a automatic machinery where a point located on the carrier link has a prescribed path while the carrier has a prescribed angular orientation. Prescribing the movement of the bucket for a bucket loader id another example of motion generation mechanisms, the path of tip of the bucket is critical since the tip must perform a scooping trajectory followed by a lifting and a dumping trajectory. The angular orientation of the bucket are equally important to ensure that load is dumped from the correct position.A cam is a convenient device for transforming one motion into another. Thismachine element has a curved or grooved surface which mates with a follower and imparts motion to it. The motion of the cam (usually rotation) is transformed into follower oscillation, translation, or both. Because of the various cam geometries and the large number of cam and follower combinations, the cam is an extremely versatile mechanical element. Although a cam and follower may be designed for motion, path, or function generation, the majority of applications utilize the cam and follower for function generation.The most common cam types according to cam shapes are: disk or plate translating (two-dimensional or planar), and cylindrical (three-dimensional or spatial) cams. Followers can be classified in several ways: according to follower motion, such as translation or oscillation; according to whether the translational (straight-line) follower motion is radial of offset from the center of the cam shaft; and according to the shape of the follower contact surface (e. g. , flat-face, roller, point (knife-edge), spherical, planar curved, or spatial-curved surface).In the case of a disk cam with a radial (in-line) translating roller follower the smallest circle that can be drawn tangent to the cam surface and concentric with the camshaft is the base circle. The tracer point is a point at the center of the roller center and the normal to the pitch curve. The pressure angle is the angle between the direction of the path of the roller center and the normal to the pitch curve through the center of the roller and is the complement of the transmission angle. Neglecting friction, this normal is collinear with the contact force between the cam and follower. As in a linkage, the pressure angle varies during the cycle and is a measure of the ability of the cam to transfer motive effort to the follower. A large pressure angle will produce an appreciable lateral force exerted on the stem of the follower, which, in the presence of friction, would tend to bind the follower in the guide.Numerous applications in automatic machinery require intermittent motion. A typical example will call for a rise-dwell-return and perhaps another dwell period of a specified number of degrees each, together with a required follower displacement measured in centimeters or degrees. The designer’s job is to lay out the cam accordingly. The first decision to be made is to choose the cam follower type. The specified application may dictate the combination of the cam and follower. Some factors that should enter into the decision are: geometric considerations, dynamic considerations, environmental considerations and economic matters. Once a type of cam and follower pair has been selected, the follower motion must be chosen. Therefore, the velocity, acceleration, and in some cases further derivatives of the displacement of the follower are of great importance.Gears are machine elements that transmit motion by means of successively engaging teeth. Gears transmit motion from one rotating shaft to another, or to a rack that translates. Numerous applications exist in which a constant angular velocity ratio (or constant torque ratio) must be transmitted between shafts. Based on the variety of gear types available, there is no restriction that the input and the output shafts need be either in-line or parallel. Nonlinear angular velocity ratios are also available by using noncircular gears. In order to maintain a constant angular velocity, the individual tooth profile must obey the fundamental law of gearing: for a pair of gears to transmita constant angular velocity ratio, the shape of their contacting profiles must be such that the common normal passes through a fixed point on the line of the centers.Any two mating tooth profiles that satisfy the fundamental law of gearing are called conjugate profiles. Although there are many tooth shapes possible in which a mating tooth could be designed to satisfy the fundamental law, only two are in general use: the cycloidal and involute profiles. The involute has important advantages: it is easy to manufacture and the center distance between a pair of involute gears can be varied without changing the velocity ratio. Thus chose tolerances between shafts are not required when utilizing the involute profile.There are several standard gear types. For applications with parallel shafts, straight spur gear, parallel helical, or herringbone gears are usually used. In the case of intersecting shafts, straight bevel of spiral bevel gears are employed. For nonintersecting and nonparallel shafts, crossed helical, worm, face, skew bevel or hypoid gears would be acceptable choices. For spur gears, the pitch circles of mating gears are tangent to each other. They roll on one another without sliding. The addendum is the height by which a tooth projects beyond the pitch circle (also the radial distance between the pitch circle and the addendum circle). The clearance is the amount by which the addendum (tooth height below the pitch circle) in a given gears exceeds the addendum of its mating gear. The tooth thickness is the distance across the tooth along the arc of the pitch circle while the tooth space is the distance between adjacent teeth along the arc of the pitch circle. The backlash is the amount by which the width of the tooth space exceeds the thickness of the engaging tooth at the pitch circle.中文译文：运动的综合，凸轮和齿轮机构是形成许多机械装置的基本几何结构单元，这些机械装置包括自动包装机、打印机、机械玩具、纺织机械和其他机械等。
机械专业外文翻译-挖掘机的机械学和液压学
┊┊┊┊┊┊┊┊┊┊┊┊┊装┊┊┊┊┊订┊┊┊┊┊线┊┊┊┊┊┊┊┊┊┊┊┊┊Multi-Domain Simulation:Mechanics and Hydraulics of an Excavator Abstract It is demonstrated how to model and simulate an excavator with Modelica and Dymola by using Modelica libraries for multi-body and for hydraulic systems. The hydraulic system is controlled by a “load sensing” controller. Usually, models containing3-dimensional mechanical and hydraulic components are difficult to simulate. At hand of the excavator it is shown that Modelica is well suited for such kinds of system simulations.1. IntroductionThe design of a new product requires a number of decisions in the initial phase that severely affect the success of the finished machine. Today, digital simulation is therefore used in early stages to look at different concepts. The view of this paper is that a new excavator is to be designed and several candidates of hydraulic control systems have to be evaluated.Systems that consist of 3-dimensional mechanical and of hydraulic components – like excavators – are difficult to simulate. Usually, two different simulation environments have to be coupled. This is often inconvenient, leads to unnecessary numerical problems and has fragile interfaces. In this article it is demonstrated at hand of the model of an excavator that Modelica is well suited for these types of systems.The 3-dimensional components of the excavator are modeled with the new, free Modelica MultiBody library. This allows especially to use an analytic solution of the kinematic loop at the bucket and to take the masses of the hydraulic cylinders, i.e., the “force elements”, directly into account. The hydraulic part is modeled in a detailed way, utilizing pump, valves and cylinders from HyLib, a hydraulics library for Modelica. For the control part a generic “load sensing” control system is used, modeled by a set of simple equations. This approach gives the required results and keeps the time needed for analyzing the problem on a reasonable level.2. Modeling ChoicesThere are several approaches when simulating a system. Depending on the task it may be necessary to build a very precise model, containing every detail of the system and needing a lot of information, e.g., model parameters. This kind of models is expensive to build up but on the other hand very useful if parameters of a well defined system have to be modified. A typical example is the optimization of parameters of a counterbalance valve in an excavator (Kraft 1996).The other kind of model is needed for a first study of a system. In this case some properties of the pump, cylinders and loads are specified. Required is information about the performance of that system, e.g., the speed of the pistons or the necessary input power at the pump shaft, to make a decision whether this design can be used in principle for the task at hand. This model has therefore to be “cheap”, i.e., it must be possible to build it in a short time without detailed knowledge of particular components.The authors intended to build up a model of the second type, run it and have first results with a minimum amount of time spent. To achieve this goal the modeling language Modelica (Modelica 2002), the Modelica simulation environment Dymola (Dymola 2003), the new Modelica library for 3-dimensional mechanical systems “MultiBody”(Otter et al. 2003) and the Modelica library of hydraulic components HyLib (Beater 2000) was used. The model consists of the 3-dimensional mechanical construction of the excavator, a detailed description of the power hydraulics and a generic “load sensing” controller. This model will be available as a demo in the next version of HyLib.3. Construction of ExcavatorsIn Figure 1 a schematic drawing of a typical excavator under consideration is shown. It consists of a chain track and the hydraulic propel drive which is used to manoeuvre the machine but usually not during a work cycle. On top of that is a carriage where the operator is sitting. It can rotate around a vertical axis with respect to the chain track. It also holds the Diesel engine, the hydraulic pumps and control system. Furthermore, there is a boom, an arm and at the end a bucket which is attached via a planar kinematic loop to the arm. Boom, arm and bucket can be rotated by the appropriate cylinders.┊┊┊┊┊┊┊┊┊┊┊┊┊装┊┊┊┊┊订┊┊┊┊┊线┊┊┊┊┊┊┊┊┊┊┊┊┊Figure 2 shows that the required pressures in the cylinders depend on the position. For the “stretched” situation the pressure in the boom cylinder is 60 % higher than in the retracted position. Not only the position but also the movements have to be taken into account. Figure 3 shows a situation where the arm hangs down. If the carriage does not rotate there is a pulling force required in the cylinder. When rotating –excavators can typically rotate with up to 12 revolutions per minute –the force in the arm cylinder changes its sign and now a pushing force is needed. This change is very significant because now the “active” chamber of the cylinder switches and that must be taken into account by the control system. Both figures demonstrate that a simulation model must take into account the couplings between the four degrees of freedom this excavator has. A simpler model that uses a constant load for each cylinder and the swivel drive leads to erroneous results4. Load Sensing SystemExcavators have typically one Diesel engine, two hydraulic motors and three cylinders. There exist different hydraulic circuits to provide the consumers with the required hydraulic energy. A typical design is a Load Sensing circuit that is energy efficient and user friendly. The idea is to have a flow rate control system for the pump such that it delivers exactly the needed flow rate. As a sensor the pressure drop across an orifice is used. The reference value is the resistance of the orifice. A schematic drawing is shown in figure 4, a good introduction to that topic is given in (anon. 1992).The pump control valve maintains a pressure at the pump port that is typically 15 bar higher than the pressure in the LS line (= Load Sensing line). If the directional valve is closed the pump has therefore a stand-by pressure of 15 bar. If it is open the pump delivers a flow rate that leads to a pressure drop of 15 bar across that directional valve. Note: The directional valve is not used to throttle the pump flow but as a flow meter (pressure drop that is fed back) and as a reference (resistance). The circuit is energy efficient because the pump delivers only the needed flow rate, the throttling losses are small compared to other circuits.If more than one cylinder is used the circuit becomes more complicated, see figure 5. E.g. if the boom requires a pressure of 100 bar and the bucket a pressure of 300 bar the pump pressure must be above 300 bar which would cause an unwanted movement of the boom cylinder. Therefore compensators are used that throttle the oil flow and thus achieve a pressure drop of 15 bar across the particular directional valve. These compensators can be installed upstream or downstream of the directional valves. An additional valve reduces the nominal pressure differential if the maximum pump flow rate or the maximum pressure is reached (see e.g. Nikolaus 1994).5. Model of Mechanical PartIn Figure 6, a Modelica schematic of the mechanical part is shown. The chain track is not modeled, i.e., it is assumed that the chain track does not move. Components “rev1”, ..., “rev4” are the 4 revolute joints to move the parts relative to each other. The icons with the long black line are “virtual”rods that are used to mark specific points on a part, especially the mounting points of the hydraulic cylinders. The light blue spheres (b2, b3, b4, b5) are bodies that have mass and an inertia tensor and are used to model the corresponding properties of the excavator parts.The three components “cyl1f”, “cyl2f”,and “cyl3f” are line force components that describe a force interaction along a line between two attachment points. The small green squares at these components represent 1-dimensional translational connectors from theModelica.Mechanics. Translational library. They are used to define the 1- dimensional force law acting between the two attachment points. Here, the hydraulic cylinders described in the next section are directly attached. The small two spheres in the icons of the “cyl1f,cyl2f, cyl3f” components indicate that optionally two point masses are taken into account that are attached at defined distances from the attachment points along the connecting line. This allows to easily model the essential mass properties (mass and center of mass) of the hydraulic cylinders with only a very small computational overhead.The jointRRR component (see right part of Figure 6) is an assembly element consisting of 3 revolute joints that form together a planar loop when connected to the arm. A picture of this part of an excavator, a zoom in the corresponding Modelica schematic and the animation view is shown in Figure 7. When moving revolute joint “rev4” (= the large red cylinder in the lower part of Figure 7; the small┊┊┊┊┊┊┊┊┊┊┊┊┊装┊┊┊┊┊订┊┊┊┊┊线┊┊┊┊┊┊┊┊┊┊┊┊┊red cylinders characterize the 3 revolute joints of the jointRRR assembly component) the position and orientation of the attachment points of the “left”and “right” revolute joints of the jointRRR component are known. There is a non-linear algebraic loop in the jointRRR component to compute the angles of its three revolute joints given the movement of these attachment points. This non-linear system of equations is solved analytically in the jointRRR object, i.e., in a robust and efficient way. For details see In a first step, the mechanical part of the excavator is simulated without the hydraulic system to test this part separatly. This is performed by attaching translational springs with appropriate spring constants instead of the hydraulic cylinders. After the animation looks fine and the forces and torques in the joints have the expected size, the springs are replaced by the hydraulic system described in the next sections.All components of the new MultiBody library have “built-in” animation definitions, i.e., animation properties are mostly deduced by default from the given definition of the multi-body system. For example, a rod connecting two revolute joints is by default visualized as cylinder where the diameter d is a fraction of the cylinder length L (d = L/40) which is in turn given by the distance of the two revolute joints. A revolute joint is by default visualized by a red cylinder directed along the axis of rotation of the joint. The default animation (with only a few minor adaptations) of the excavator is shown if Figure 8. The light blue spheres characterize the center of mass of bodies. The line force elements that visualize the hydraulic cylinders are defined by two cylinders (yellow and grey color) that are moving in each other. As can be seen, the default animation is useful to get, without extra work from the user side, a rough picture of the model that allows to check the most important properties visually, e.g., whether the center of masses or attachment points are at the expected places.For every component the default animation can be switched off via a Boolean flag. Removing appropriate default animations, such as the “centerof- mass s pheres”, and adding some components that have pure visual information (all visXXX components in the schematic of Figure 6) gives quickly a nicer animation, as is demonstrated in Figure 9. Also CAD data could be utilized for the animation, but this was not available for the examination of this excavator.6. The Hydraulics Library HyLibThe (commercial) Modelica library HyLib (Beater 2000, HyLib 2003) is used to model the pump, metering orifice, load compensator and cylinder of the hydraulic circuit. All these components are standard components for hydraulic circuits and can be obtained from many manufacturers. Models of all of them are contained in HyLib. These mathematical models include both standard textbook models (e. g. Dransfield 1981, Merrit 1967, Viersma 1980) and the most advanced published models that take the behavior of real components into account (Schulz 1979, Will 1968). An example is the general pump model where the output flow is reduced if pressure at the inlet port falls below atmospheric pressure. Numerical properties were also considered when selecting a model (Beater 1999). One point worth mentioning is the fact that all models can be viewed at source code level and are documented by approx. 100 references from easily available literature.After opening the library, the main window is displayed (Figure 10). A double click on the “pumps” icon opens the selection for all components that are needed to originate or end an oil flow (Figure 11). For the problem at hand, a hydraulic flow source with internal leakage and externally commanded flow rate is used. Similarly the needed models for the valves, cylinders and other components are chosen.All components are modeled hierarchically. Starting with a definition of a connector –a port were the oil enters or leaves the component – a template for components with two ports is written. This can be inherited for ideal models, e.g., a laminar resistance or a pressure relief valve. While it usually makes sense to use textual input for these basic models most of the main library models were programmed graphically, i.e., composed from basic library models using the graphical user interface. Figure12 gives an example of graphical programming. All mentioned components were chosen from the library and then graphically connected.7. Library Components in Hydraulics CircuitThe composition diagram in Figure 12 shows the graphically composed hydraulics part of the excavator model. The sub models are chosen from the appropriate libraries, connected and the┊┊┊┊┊┊┊┊┊┊┊┊┊装┊┊┊┊┊订┊┊┊┊┊线┊┊┊┊┊┊┊┊┊┊┊┊┊parameters input. Note that the cylinders and the motor from HyLib can be simply connected to the also shown components of the MultiBody library. The input signals, i.e., the reference signals of the driver of the excavator, are given by tables, specifying the diameter of the metering orifice, i.e. the reference value for the flow rate. From the mechanical part of the excavator only the components are shown in Figure 12 that are directly coupled with hydraulic elements, such as line force elements to which the hydraulic cylinders are attached.8. Model of LS ControlFor this study the following approach is chosen: Model the mechanics of the excavator, the cylinders and to a certain extent the pump and metering valves in detail because only the parameters of the components will be changed, the general structure is fixed. This means that the diameter of the bucket cylinder may be changed but there will be exactly one cylinder working as shown in Figure 1. That is different for the rest of the hydraulic system. In this paper a Load Sensing system, or LS system for short, using one pump is shown but there are other concepts that have to be evaluated during an initial design phase. For instance the use of two pumps, or a separate pump for the swing.The hydraulic control system can be set up using meshed control loops. As there is (almost) no way to implement phase shifting behavior in purely hydraulic control systems the following generic LS system uses only proportional controllers.A detailed model based on actual components would be much bigger and is usually not available at the begin of an initial design phase. It could be built with the components from the hydraulics library but would require a considerable amount of time that is usually not available at the beginning of a project.In Tables 1 and 2, the implementation of the LS control in form of equations is shown. Usually, it is recommended for Modelica models to either use graphical model decomposition or to define the model by equations, but not to mix both descrip- tion forms on the same model level.For the LS system this is different because it has 17 input signals and 5 output signals. One might built one block with 17 inputs and 5 outputs and connect them to the hydraulic circuit. However, in this case it seems more understandable to provide the equations directly on the same level as the hydraulic circuit above and access the input and output signals directly. For example, ”metOri1.port_A.p” used in table 2 is the measured pressure at port_A of the metering orifice metOri1. The calculated values of the LS controller, e.g., the pump flow rate “pump.inPort.signal[1] = ...” is the signal at the filled blue rectangle of the “pump” component, see Figure 12).The strong point of Modelica is that a seamless integration of the 3-dimensional mechanical library, the hydraulics library and the non standard, and therefore in no library available, model of the control system is easily done. The library components can be graphically connected in the object diagram and the text based model can access all needed variables.9. Some Simulation ResultsThe complete model was built using the Modelica modeling and simulation environment Dymola (Dymola 2003), translated, compiled and simulated for 5 s. The simulation time was 17 s using the DASSL integrator with a relative tolerance of 10-6 on a 1.8 GHz notebook, i.e., about 3.4 times slower as real-time. The animation feature in Dymola makes it possible to view the movements in an almost realistic way which helps to explain the results also to non-experts, see Figure 9.Figure 13 gives the reference signals for the three cylinders and the swing, the pump flow rate and pressure. From t = 1.1 s until 1.7 s and from t = 3.6 s until 4.0 s the pump delivers the maximum flow rate. From t = 3.1 s until 3.6 s the maximum allowed pressure is reached. Figure 14 gives the position of the boom and the bucket cylinders and the swing angle. It can be seen that there is no significant change in the piston movement if another movement starts or ends. The control system reduces the couplings between the consumers which are very severe for simple throttling control.Figure 15 shows the operation of the bucket cylinder. The top figure shows the reference trajectory, i. e. the opening of the directional valve. The middle figure shows the conductance of the compensators. With the exception of two spikes it is open from t = 0 s until t = 1 s. This means that in┊┊┊┊┊┊┊┊┊┊┊┊┊装┊┊┊┊┊订┊┊┊┊┊线┊┊┊┊┊┊┊┊┊┊┊┊┊that interval the pump pressure is commanded by that bucket cylinder. After t = 1 s the boom cylinder requires a considerably higher pressure and the bucket compensator therefore increases the resistance (smaller conductance). The bottom figure shows that the flow rate control works fine. Even though there is a severe disturbance (high pump pressure after t = 1 s due to the boom) the commanded flow rate is fed with a small error to the bucket cylinder.10. ConclusionFor the evaluation of different hydraulic circuits a dynamic model of an excavator was built. It consists of a detailed model of the 3 dimensional mechanics of the carriage, including boom, arm and bucket and the standard hydraulic components like pump or cylinder. The control system was not modeled on a component basis but the system was described by a set of nonlinear equations.The system was modeled using the Modelica MultiBody library, the hydraulics library Hylib and a set of application specific equations. With the tool Dymola the system could be build and tested in a short time and it was possible to calculate the required trajectories for evaluation of the control system.The animation feature in Dymola makes it possible to view the movements in an almost realistic way which helps to explain the results also to多畴模拟：挖掘机的机械学和液压学概要：通过使用用于多体和液压系统的Modelica程序库，示范通过Modelica和Dymola如何模拟和仿真挖掘机。
机械工程及自动化专业外文翻译--机械工程
外文原文：Mechanical engineering1.The porfile of mechanical engineeringEngingeering is a branch of mechanical engineerig,it studies mechanical and power generation especially power and movement.2.The history of mechanical engineering18th century later periods,the steam engine invention has provided a main power fountainhead for the industrial revolution,enormously impelled each kind of mechznical biting.Thus,an important branch of a new Engineering –separated from the civil engineering tools and machines on the branch-developed together with Birmingham and the establishment of the Associantion of Mechanical Engineers in 1847 had been officially recognized.The mechanical engineering already mainly used in by trial and error method mechanic application technological development into professional engineer the scientific method of which in the research,the design and the realm of production used .From the most broad perspective,the demend continuously to enhance the efficienceyof mechanical engineers improve the quality of work,and asked him to accept the history of the high degree ofeducation and training.Machine operation to stress not only economic but also infrastructure costs to an absolute minimun.3.The field of mechanical engineeringThe commodity machinery development in the develop country,in the high level material life very great degree is decided each kind of which can realize in the mechanical engineering.Mechanical engineers unceasingly will invent the machine next life to produce the commodity,unceasingly will develop the accuracy and the complexity more and more high machine tools produces the machine.The main clues of the mechanical development is:In order to enhance the excellent in quality and reasonable in price produce to increase the precision as well as to reduce the production cost.This three requirements promoted the complex control system development.The most successful machine manufacture is its machine and the control system close fusion,whether such control system is essentially mechanical or electronic.The modernized car engin production transmission line(conveyer belt)is a series of complex productions craft mechanization very good example.The people are in the process of development in order to enable further automation of the production machinery ,the use of a computer to store and handle largevolumes of data,the data is a multifunctional machine tools necessary for the production of spare parts.One of the objectives is to fully automated production workshop,three rotation,but only one officer per day to operate.The development of production for mechanical machinery must have adequate power supply.Steam engine first provided the heat to generate power using practical methods in the old human,wind and hydropower,an increase of engin .New mechanical engineering industry is one of the challenges faced by the initial increase thermal effciency and power,which is as big steam turbine and the development of joint steam boilers basically achieved.20th century,turbine generators to provide impetus has been sustained and rapid growth,while thermal efficiency is steady growth,and large power plants per kW capital consumption is also declining.Finally,mechanical engineers have nuclear energy.This requires the application of nuclear energy particularly high reliability and security, which requires solving many new rge power plants and the nuclear power plant control systems have become highly complex electroonics,fluid,electricity,water and mechanical parts networks All in all areas related to the mechanical engineers.Small internal combustion engine,both to the type(petrol and diesel machines)or rotary-type(gas turbines and Mong Kerr machine),as well as their broad application in the field of transport should also due to mechanical enginerrs.Throughout the transport,both in the air and space,or in the terrestrial and marine,mechanial engineers created a variety of equipment and power devices to their increasing cooperation with electrical engineers,especially in the development of appropration control systems.Mechanical engineers in the development of military weapons technology and civil war ,needs a similar,though its purpose is to enhance rather than destroy their productivity.However.War needs a lot of resources to make the area of techonlogy,many have a far-reaching development in peacetime efficiency.Jet aircraft and nuclear reactors are well known examples.The Biological engineering,mechanical engineering biotechnology is a relatively new and different areas,it provides for the replacement of the machine or increase the body functions as well as for medical equipment.Artficial limbs have been developed and have such a strong movement and touch response function of the human body.In the development of artificial organ transplant is rapid,complex cardiac machines and similar equipment to enable increasingly complexsurgery,and injuries and ill patients life functions can be sustained.Some enviromental control mechanical engineers through the initial efforts to drainage or irrigation pumping to the land and to mine and ventilation to control the human environment.Modern refrigeration and air-conditioning plant commonaly used reverse heat engine,where the heat from the engine from cold places to more external heat.Many mechanical engineering products,as well as other leading technology development city have side effects on the environment,producing noise,water and air pollution caused,destroyed land and landscape.Improve productivity and diver too fast in the commodity,that the renewable natural forces keep pace.For mechanical engineers and others,environmental control is rapidly developing area,which includes a possible development and production of small quantities of pollutants machine sequnce,and the development of new equipment and teachnology has been to reduce and eliminate pollution.4.The role of mechanical engineeringThere are four generic mechanical engineers in common to the above all domains function.The 1st function is the understanding and the research mechanical sciencefoundation.It includes the power and movement of the relationship dynamics For example,in the vibration and movement of the relationship;Automatic control;Study of the various forms of heart,energy,power relations between the thermodynamic;Fluidflows; Heat transfer; Lubricant;And material properties.The 2nd function will be conducts the research,the desing and the development,this function in turn attempts to carry on the essential change to satisfy current and the future needs.This not only calls for a clear understanding of mechanical science,and have to break down into basic elements of a complex system capacity.But also the need for synthetic and innovative inventions.The 3rd function is produces the product and the power,include plan,operation and maintenance.Its goal lies in the maintenance either enhances the enterprise or the organization longer-tern and survivabilaty prestige at the same time,produces the greatest value by the least investments and the consumption.The 4th function is mechanical engineer’s coordinated function,including the management,the consultation,as well as carries on the market marking in certain situation.In all these function,one kind unceasingly to use thescience for a long time the method,but is not traditional or the intuition method tendency,this is a mechanical engineering skill aspect which unceasingly grows.These new rationalization means typical names include:The operations research,the engineering economics,the logical law problem analysis(is called PABLA) However,creativity is not rationalization.As in other areas,in mechanical engineering,to take unexpected and important way to bring about a new capacity,still has a personal,marked characteristice.5.The design of mechanical engineeringThe design of mechanical is the design has the mechanical property the thing or the system,such as:the instrument and the measuring appliance in very many situations,the machine design must use the knowledge of discipline the and so on mathematics,materials science and mechanics.Mechanical engineering desgin includeing all mechanical desgin,but it was a study,because it also includes all the branches of mechsnical engineering,such as thermodynamics all hydrodynamics in the basic disciplines needed,in the mechanical engineering design of the initial stude or mechanical design.Design stages.The entire desgin process from start to finish,in the process,a demand that is designed forit and decided to do the start.After a lot of repetition,the final meet this demand by the end of the design procees and the plan.Design considerations.Sometimes in a system is to decide which parts needs intensity parts of geometric shapesand size an important factor in this context that we must consider that the intensity is an important factor in the design.When we use expression design considerations,we design parts that may affect the entire system design features.In the circumstances specified in the design,usually for a series of such functions must be taken into account.Howeever,to correct purposes,we should recognize that,in many cases the design of important design considerations are not calculated or test can determine the components or systems.Especially students,wheen in need to make important decisions in the design and conduct of any operation that can not be the case,they are often confused.These are not special,they occur every day,imagine,for example,a medical laboratory in the mechanical design,from marketing perspective,people have high expectations from the strength and relevance of impression.Thick,and heavy parts installed together:to produce a solid impression machines.And sometimes machinery and spare parts from the design style is the point and not theother point of view.Our purpose is to make those you do not be misled to believe that every design decision will need reasonable mathematical methods.Manufacturing refers to the raw meterials into finished products in the enterprise.Create three distinct phases.They are:input,processing exprot.The first phase includes the production of all products in line with market needs essential.First there must be the demand for the product,the necessary materials,while also needs such as energy,time,human knowledge and technology resourcess .Finall,the need for funds to obtain all the other resources. Lose one stage after the second phase of the resources of the processes to be distributed.Processing of raw materials into finished products of these processes.To complete the design,based on the design,and then develop plans.Plan implemented through various production processes.Management of resources and processes to ensure efficiency and productivity.For example,we must carefully manage resources to ensure proper use of funds.Finally,people are talking about the product market was cast.Stage is the final stage of exporting finished or stage.Once finished just purchased,it must be delivered to the users.According to productperformance,installation and may have to conduct further debugging in addition,some products,especially those very complex products User training is necessary.6.The processes of materials and maunfacturingHere said engineering materials into two main categories:metals and non-ferrous,high-performance alloys and power metals.Non-metallic futher divided into plastice,synthetic rubber,composite materials and ceramics.It said the production proccess is divided into several major process,includingshape,forging,casting/ founding,heat treatment,fixed/connections ,measurement/ quality control and materal cutting.These processes can be further divide into each other’s craft.Various stages of the development of the manufacturing industry Over the years,the manufacturing process has four distinct stages of development, despite the overlap.These stages are:The first phase is artisanal,the second Phase is mechanization.The third phase is automation the forth Phase is integrated.When mankind initial processing of raw materials into finished products will be,they use manual processes.Each with their hands and what are the tools manuslly produced.This is totally integrated production take shape.A person needsindentification,collection materials,the design of a product to meet that demand,the production of such products and use it.From beginning to end,everything is focused on doing the work of the human ter in the industrial revolution introduced mechanized production process,people began to use machines to complete the work accomplished previously manual. This led to the specialization.Specialization in turn reduce the manufacture of integrated factors.In this stage of development,manufacturing workers can see their production as a whole represent a specific piece of the part of the production process.One can not say that their work is how to cope with the entire production process,or how they were loaded onto a production of parts finished.Development of manufacting processes is the next phase of the selection process automation.This is a computer-controlled machinery and processes.At this stage,automation island began to emerge in the workshop lane.Each island represents a clear production process or a group of processes.Although these automated isolated island within the island did raise the productivity of indivdual processes,but the overall productivity are often not change.This is because the island is not caught in other automated production process middle,but not synchronous withthem .The ultimate result is the efficient working fast parked through automated processes,but is part of the stagnation in wages down,causing bottlenecks.To better understand this problem,you can imagine the traffic in the peak driving a red light from the red Service Department to the next scene. Occasionally you will find a lot less cars,more than being slow-moving vehicles,but the results can be found by the next red light Brance.In short you real effect was to accelerate the speed of a red Department obstruction offset.If you and other drivers can change your speed and red light simultaneously.Will advance faster.Then,all cars will be consistent,sommth operation,the final everyone forward faster.In the workshop where the demand for stable synchronization of streamlined production,and promoted integration of manufacturing development.This is a still evolving technology.Fully integrated in the circumstances,is a computer-controllrd machinery and processing.integrated is completed through computer.For example in the preceding paragraph simulation problems,the computer will allow all road vehicles compatible with the change in red.So that everyone can steady traffic.Scientific analysis of movement,timing and mechanics of the disciplines is that it is composed of two pater:statics anddynamics.Statics analyzed static system that is in the system,the time is not taken into account,research and analysis over time and dynamics of the system change.Dynameics from the two componets.Euler in 1775 will be the first time two different branches: Rigid body movement studies can conveniently divided into two parts:geometric and mechanics.The first part is without taking into account the reasons for the downward movement study rigid body from a designated location to another point of the movement,and must use the formula to reflect the actual,the formula would determine the rigid body every point position. Therefore,this study only on the geometry and,more specifically,on the entities from excision.Obviously,the first part of the school and was part of a mechanical separation from the principles of dynamics to study movement,which is more than the two parts together into a lot easier.Dynamics of the two parts are subsequently divided into two separate disciplines,kinematic and dynamics,a study of movement and the movement strength.Therefore,the primary issue is the design of mechanical systems understand its kinematic.Kinematic studies movement,rather than a study of its impact.In a more precise kinematic studies position,displacement,rotation,speed,velocity and acceleration of disciplines,for esample,or planets orbiting research campaing is a paradigm.In the above quotation content should be pay attention that the content of the Euler dynamics into kinematic and rigid body dynamics is based on the assumption that they are based on research.In this very important basis to allow for the treatment of two separate disciplines.For soft body,soft body shape and even their own soft objects in the campaign depends on the role of power in their possession.In such cases,should also study the power and movement,and therefore to a large extent the analysis of the increased complexity.Fortunately, despite the real machine parts may be involved are more or less the design of machines,usually with heavy material designed to bend down to the lowest parts.Therefore,when the kinematic analysis of the performance of machines,it is often assumed that bend is negligible,spare parts are hard,but when the load is known,in the end analysis engine,re-engineering parts to confirm this assnmption.中文译文：机械工程1.机械工程简介机械工程是工程学的一个分支，它研究机械和动力的产，尤其是力和动力。
机械专业外文翻译---残余应力
中文2748字附录Residual StressesA residual stress is one that exists without external loading or internal temperature differences on a structure or machine. It is usually a result of manufacturing or assembling operations. Sometimes it is called initial stress, and the operations, prestressing. When the structure or machine is put into service, the service loads superimpose stresses. If the residual stresses add to the service-load stresses, they are detrimental; if they subtract from the service-load stresses they are beneficial.In the plastic deformation the external force does the merit turns into outside the heat except the majority of extensions, but also some small part by the distortion can the form stores up in the deformation material. This part of energy named storage energy. The storage can the concrete manifestation way is: Macroscopic residual stress, microscopic residual stress and lattice distortion. According to the residual stress balance scope difference, usually may divide into it three kinds:(1) First kind of internal stress, also called the macroscopic residual stress, it is causes by the work piece different part macroscopic distortion nonuniformity, therefore its stress balance scope including entire work piece. For example, serves with Jin Shubang the curving load, then above is pulled elongates, under receives the compression; The distortion surpasses when the limit of elasticity has had the plastic deformation, after then the external force elimination by elongated one side on the existence compressed stress, the leg of right triangle is the tensile stress. This kind of residual stress corresponds the distortion can not be big, only accounts for always stores up can about 0.1%.(2) Second kind of internal stress, also called the microscopic residual stress, it is produces by between the crystal grain or the subgraindistortion nonuniformity. Its sphere of action and the crystal grain size quite, namely maintain the balance between the crystal grain or the subgrain. Sometimes this kind of internal stress may achieve the very great value, even possibly creates the micro crack and causes the work piece destruction.(3) Third kind of internal stress, also calls the lattice distortion. Its sphere of action is several dozens to several hundred nanometers, it is because the work piece forms in the plastic deformation the massive lattice flaw (for example vacancy, interstitial atom, dislocation and so on) cause. In the distortion metal the storage can the major part (80%~90%) uses in forming the lattice distortion. This part of energy enhanced the distortion crystal energy, causes it to be at the thermodynamics non-steady state, therefore it has one kind to make the distortion metal to restore to the free enthalpy lowest stable structure condition spontaneous tendency, and causes the plastic deformation metal in heating time reply and the recrystallization process.Only a few examples of detrimental residual stresses will be given here .One, in the assembly of machinery, occurs when two shafts are not in line or are a few thousandths of an inch out of parallel, and they are forced into connection by rigid couplings. The resulting stresses in the shafts become reversing stresses when the shafts are rotated. The correction, when perfect alignment cannot be economically attained, as is frequently the case, is to use flexible couplings of a type necessary for the degree of misalignment.The preceding case occurs with elastic stresses only, and the residual stresses are maintained by bearing constraints. In applications where mechanical work causes plastic yielding .stresses remain when the constraints are removed. For example, the forging of shafts and crankshafts and the cooling after forging may induce residual stresses, the equilibrium of which id changed in machining, causing some warping of the shafts. It is then common practice to straighten the shafts in a pressbefore the final machining operation. Straightening requires a bending moment large enough to cause permanent set or yielding.Detrimental residual stresses commonly result from differential heating or cooling. A weld is a common example, The weld metal and the areas immediately adjacent are, after solidification, at a much higher temperature than the main body of metal. The natural contraction of the metal along the length of the weld is partially prevented by the large adjacent body of cold metal. Hence residual tensile stresses are set up along the weld.In general, local or shallow heating which would expand the region or surface, if it were free, a distance well beyond that which the adjacent larger volume will allow causes yielding and upsetting of the heated material, This readily occurs because of the reduced yield strength at elevated temperatures. The same cooler volume prevents the upset, heated region from fully contracting during its cooling, and tensile general rule is that the “last to cool is in tension,”although there is an exception if certain transformations of microstructure occur. Methods for minimizing or reversing these stresses include annealing for stress relief and hammer or shot peening of the weakened surface. Annealing requires heating mild steel to 1100~1200F, followed by slow cooling, Some preheating of the parts to be joined may minimize the tensile stresses in welds.A thin but highly effective surface layer of compressive stress may be induced by cold-rolling, coining, and peening processes. It is seen that these processes work-harden an outer layer, thus causing compressive stresses to remain, together with minor tensile stresses in adjacent interior layers. Since the compressive layer is readily obtained all around, these processes are suitable for reversing loads and rotating components where the stress varies between tension and compression. The processes must be carefully controlled in respect to roller pressures and feeds, shot size and speed, etc., for which extensive information is available in engineering books and periodicals.Cold-rolling is applied primarily to cylindrical and other shapes that can be rotated, such as threads and shaft fillets. The shape, size, and pressure of the roller and the yield strength of the shaft determine the depth of penetration, which can be calculated. A special fixture may be attached to the carriages of a lathe and made to slowly traverse the desired rolling of bolts and screws has long been part of a forming process that not only forms but strengthens the threads by deformation and grain flow around the roots and by inducing compressive residual stresses.Coining of holes, also called ball drifting, is a manufacturing process of forcing a hard, tungsten carbide or AIDI 52100 steel, slightly oversize ball through a hole in a plate, bushing, or tubing to give the holes final size and a fine finish. The length of the hole may be from 1/20 to 10 times its diameter. The machine is often set up for a high production of small parts with unskilled labor. An incidental result is that the process increases hardness, hence wear resistance, and induces around the hole a compressive residual stress that is usually advantageous, as in roller-chain links. The links ate highly stressed in pulsating tension with a concentration of the stress at and near the hole surfaces. With the compressive stress from ball drifting, the net tensile stress in service is decreased, and failure is minimized.Peening is the most widely used method for prestressing by mechanically induced yielding. By the impact of rounded striking objects, the surface is deformed in a multitude of shallow dimples, which in trying to expand put the surface under compression. Hammer peening, usually by air-driven tool with a rounded end, is useful on limited areas, such as a weld in shaft or on areas found weakened by corrosion, decarburization, or minor fatigue damage. With a hard spherical end to the tool, the depth of the compressed layer, which occurs below the surface, is about half the strain-hardened region.Shot peening is done on steels by the high-velocity impingement ofsmall, round, steel or chilled cast-iron shot with diameters from 0.007to 0.175 in.. The compressed layer has a depth from a few thousandths to a few hundredths of an inch, less than with hammer peening, but roughly proportioned to the shot size used and its velocity. Again the residual stress produced is about half of the strain-hardened yield strength.Shot peening is extensively used because it may be applied with minimum cost to most metals and shapes, except some interior ones. On soft metals, glass beads may be used. Helical springs are commonly shot peened, with up to a 60%increase in allowable stress under pulsating loads. Part of the improvement may be due to the removal of the weakening longitudinal scratches left from the wire-drawing operation. Similarly, coarse-machined and coarse-ground surfaces are smoothed and improved by shot peening, which may be a more economical method than producing a final finish by machining or grinding. Peening is not used on bearing and other closely fitting surfaces where high precision is required.A final grinding for accuracy after peening would remove part or all of the residual stress. Machines are available for the automatic and continuous peening of small-and medium-size parts moving on a conveyor or turntable through the blast.残余应力残余应力是结构或者机器中在没有外部载荷或者内部温差时存在的一种应力，它通常是在制造或者装配过程中所产生的。
机械专业毕业设计外文翻译1
本科毕业设计（本科毕业论文）外文文献及译文文献、资料题目：High-rise Tower Crane designed文献、资料来源：期刊（著作、网络等）文献、资料发表（出版）日期：2000.3.25院（部）：机电工程学院专业：机电工程及自动化High-rise Tower Crane designed under Turbulent Winds At present, construction of tower cranes is an important transport operations lifting equipment, tower crane accident the people's livelihood, major hazards, and is currently a large number of tower crane drivers although there are job permits, due to the lack of means to monitor and review the actual work of a serious violation . Strengthen the inspection and assessment is very important. Tower crane tipping the cause of the accident can be divided into two aspects: on the one hand, as a result of the management of tower cranes in place, illegal operation, illegal overloading inclined cable-stayed suspended widespread phenomenon; Second, because of the tower crane safety can not be found in time For example,Took place in the tower crane foundation tilt, micro-cracks appear critical weld, bolts loosening the case of failure to make timely inspection, maintenance, resulting in the continued use of tower cranes in the process of further deterioration of the potential defect, eventually leading to the tower crane tipping. The current limit of tower crane and the black box and can not be found to connect slewing tower and high-strength bolts loosening tightened after the phenomenon is not timely, not tower verticality of the axis line of the lateral-line real-time measurement, do not have to fight the anti-rotation vehicles, lifting bodies plummeted Meng Fang, hook hoists inclined cable is a timely reminder and record of the function, the wind can not be contained in the state of suspended operation to prevent tipping on the necessary tips on site there is a general phenomenon of the overloaded overturning of the whole security risks can not be accurately given a reminder and so on, all of which the lease on the tower crane, use, management problems,Through the use of tower crane anti-tipping monitor to be resolved. Tower crane anti-tipping Monitor is a new high-tech security monitoring equipment, and its principle for the use of machine vision technology and image processing technology to achieve the measurement of the tilt tower, tower crane on the work of state or non-working state of a variety of reasons angle of the tower caused by the critical state to achieve the alarm, prompt drivers to stop illegal operation, a computer chip at the same time on the work of the state of tower crane be recorded. Tower crane at least 1 day overload condition occurs, a maximum number of days to reach 23 overloading, the driver to operate the process of playing the anti-car, stop hanging urgency, such as cable-stayed suspended oblique phenomenon often, after verification and education, to avoid the possible occurrence of fatal accidents. Wind conditions in the anti-tipping is particularly important, tower cranes sometimes connected with the pin hole and pin do not meet design requirements, to connect high-strength bolts are not loose in time after the tightening of the phenomenon, through timely maintenance in time after the tightening of the phenomenon, through timely maintenance and remedial measures to ensure that the safe and reliable construction progress. Reduced lateral line tower vertical axis measuring the number of degrees,Observation tower angle driver to go to work and organize the data once a month to ensure that the lateral body axis vertical line to meet the requirements, do not have to every time and professionals must be completed by Theodolite tower vertical axismeasuring the lateral line, simplified the management link. Data logging function to ensure that responsibility for the accident that the scientific nature to improve the management of data records for the tower crane tower crane life prediction and diagnosis of steel structures intact state data provides a basis for scientific management and proactive prevention of possible accidents, the most important thing is, if the joint use of the black box can be easily and realistically meet the current provisions of the country's related industries. Tower crane safety management at the scene of great importance occurred in the construction process should be to repair damaged steel, usually have to do a good job in the steel tower crane maintenance work and found that damage to steel structures, we must rule out potential causes of accidents, to ensure safety in production carried out smoothly. Tower crane in the building construction has become essential to the construction of mechanical equipment, tower crane at the construction site in the management of safety in production is extremely important. A long time, people in the maintenance of tower crane, only to drive attention to the conservation and electrical equipment at the expense of inspection and repair of steel structures, to bring all kinds of construction accidents.Conclusion: The tower crane anti-tipping trial monitor to eliminate potential causes of accidents to provide accurate and timely information, the tower crane to ensure the smooth development of the leasing business, the decision is correct, and should further strengthen and standardize the use of the environment (including new staff training and development of data processing system, etc.).The first construction cranes were probably invented by the Ancient Greeks and were powered by men or beasts of burden, such as donkeys. These cranes were used for the construction of tall buildings. Larger cranes were later developed, employing the use of human treadwheels, permitting the lifting of heavier weights. In the High Middle Ages, harbour cranes were introduced to load and unload ships and assist with their construction – some were built into stone towers for extra strength and stability. The earliest cranes were constructed from wood, but cast iron and steel took over with the coming of the Industrial Revolution.For many centuries, power was supplied by the physical exertion of men or animals, although hoists in watermills and windmills could be driven by the harnessed natural power. The first 'mechanical' power was provided by steam engines, the earliest steam crane being introduced in the 18th or 19th century, with many remaining in use well into the late 20th century. Modern cranes usually use internal combustion engines or electric motors and hydraulic systems to provide a much greater lifting capability than was previously possible, although manual cranes are still utilised where the provision of power would be uneconomic.Cranes exist in an enormous variety of forms – each tailored to a specific use. Sizes range from the smallest jib cranes, used inside workshops, to the tallest tower cranes,used for constructing high buildings, and the largest floating cranes, used to build oil rigs and salvage sunken ships.This article also covers lifting machines that do not strictly fit the above definition of a crane, but are generally known as cranes, such as stacker cranes and loader cranes.The crane for lifting heavy loads was invented by the Ancient Greeks in the late 6th century BC. The archaeological record shows that no later than c.515 BC distinctive cuttings for both lifting tongs and lewis irons begin to appear on stone blocks of Greek temples. Since these holes point at the use of a lifting device, and since they are to be found either above the center of gravity of the block, or in pairs equidistant from a point over the center of gravity, they are regarded by archaeologists as the positive evidence required for the existence of the crane.The introduction of the winch and pulley hoist soon lead to a widespread replacement of ramps as the main means of vertical motion. For the next two hundred years, Greek building sites witnessed a sharp drop in the weights handled, as the new lifting technique made the use of several smaller stones more practical than of fewer larger ones. In contrast to the archaic period with its tendency to ever-increasing block sizes, Greek temples of the classical age like the Parthenon invariably featured stone blocks weighing less than 15-20 tons. Also, the practice of erecting large monolithic columns was practically abandoned in favour of using several column drums.Although the exact circumstances of the shift from the ramp to the crane technology remain unclear, it has been argued that the volatile social and political conditions of Greece were more suitable to the employment of small, professional construction teams than of large bodies of unskilled labour, making the crane more preferable to the Greek polis than the more labour-intensive ramp which had been the norm in the autocratic societies of Egypt or Assyria.The first unequivocal literary evidence for the existence of the compound pulley system appears in the Mechanical Problems (Mech. 18, 853a32-853b13) attributed to Aristotle (384-322 BC), but perhaps composed at a slightly later date. Around the same time, block sizes at Greek temples began to match their archaic predecessors again, indicating that the more sophisticated compound pulley must have found its way to Greek construction sites by then.During the High Middle Ages, the treadwheel crane was reintroduced on a large scale after the technology had fallen into disuse in western Europe with the demise of the Western Roman Empire. The earliest reference to a treadwheel (magna rota) reappears in archival literature in France about 1225, followed by an illuminated depiction in a manuscript of probably also French origin dating to 1240. In navigation, the earliest uses of harbor cranes are documented for Utrecht in 1244, Antwerp in 1263, Brugge in 1288 and Hamburg in 1291, while in England the treadwheel is not recorded before 1331.Generally, vertical transport could be done more safely and inexpensively by cranes than by customary methods. Typical areas of application were harbors, mines, and, in particular, building sites where the treadwheel crane played a pivotal role in the construction of the lofty Gothic cathedrals. Nevertheless, both archival and pictorial sources of the time suggest that newly introduced machines like treadwheels or wheelbarrows did not completely replace more labor-intensive methods like ladders, hods and handbarrows. Rather, old and new machinery continued to coexist on medieval construction sites and harbors.Apart from treadwheels, medieval depictions also show cranes to be powered manually by windlasses with radiating spokes, cranks and by the 15th century also by windlasses shaped like a ship's wheel. To smooth out irregularities of impulse and get over 'dead-spots' in the lifting process flywheels are known to be in use as early as 1123.The exact process by which the treadwheel crane was reintroduced is not recorded, although its return to construction sites has undoubtedly to be viewed in close connection with the simultaneous rise of Gothic architecture. The reappearance of the treadwheel crane may have resulted from a technological development of the windlass from which the treadwheel structurally and mechanically evolved. Alternatively, the medieval treadwheel may represent a deliberate reinvention of its Roman counterpart drawn from Vitruvius' De architectura which was available in many monastic libraries. Its reintroduction may have been inspired, as well, by the observation of the labor-saving qualities of the waterwheel with which early treadwheels shared many structural similarities.In contrast to modern cranes, medieval cranes and hoists - much like their counterparts in Greece and Rome - were primarily capable of a vertical lift, and not used to move loads for a considerable distance horizontally as well. Accordingly, lifting work was organized at the workplace in a different way than today. In building construction, for example, it is assumed that the crane lifted the stone blocks either from the bottom directly into place, or from a place opposite the centre of the wall from where it could deliver the blocks for two teams working at each end of the wall. Additionally, the crane master who usually gave orders at the treadwheel workers from outside the crane was able to manipulate the movement laterally by a small rope attached to the load. Slewing cranes which allowed a rotation of the load and were thus particularly suited for dockside work appeared as early as 1340. While ashlar blocks were directly lifted by sling, lewis or devil's clamp (German Teufelskralle), other objects were placed before in containers like pallets, baskets, wooden boxes or barrels.It is noteworthy that medieval cranes rarely featured ratchets or brakes to forestall the load from running backward.[25] This curious absence is explained by the high friction force exercised by medieval treadwheels which normally prevented the wheel from accelerating beyond control.目前，塔式起重机是建筑工程进行起重运输作业的重要设备，塔机事故关系国计民生、危害重大，而目前众多的塔机司机虽然有上岗证，由于缺少监督和复核手段，实际工作中违规严重。
机械制造专业外文翻译--机械设计及加工工艺1
外文原文：Mechanical Design and Manufacturing ProcessesMechanical design is the application of science and technology to devise new or improved products for the purpose of satisfying human needs. It is a vast field of engineering technology which not only concerns itself with the original conception of the product in terms of its size, shape and construction details, but also considers the various factors involved in the manufacture, marketing and use of the product.People who perform the various functions of mechanical design are typically called designers, or design engineers. Mechanical design is basically a creative activity. However, in addition to being innovative, a design engineer must also have a solid background in the areas of mechanical drawing, kinematics,dynamics, materials engineering, strength ofmaterials and manufacturing processes.As stated previously, the purpose of mechanical design is to produce a product which will serve a need for man. Inventions, discoveries and scientific knowledge by themselves do not necessarily benefit people; only if they are incorporated into a designed product will a benefit be derived. It should berecognized,therefore, that a human need must be identified before a particular product is designed.Mechanical design should be considered to be an opportunity to use innovative talents to envision a design of a product, to analyze the system and then make sound judgments on how the product is to be manufactured. It is important to understand the fundamentals of engineering rather than memorize mere facts and equations. There are no facts or equations which alone can be used to provide all the correct decisions required to produce a good design.On the other hand, any calculations made must be done with the utmost care and precision. For example, if a decimal point is misplaced, an otherwise acceptable design may not function.Good designs require trying new ideas and being willing to take a certain amount of risk, knowing that if the new idea does not work the existing method can be reinstated. Thus a designer must have patience, since there is no assurance of success for the time and effort expended. Creating a completely new design generally requires that many old and well-established methods be thrust aside. This is not easy sincemany people cling to familiar ideas, techniques and attitudes. A design engineer should constantly search for ways to improve an existing product and must decide what old, proven concepts should be used and what new, untried ideas should be incorporated.New designs generally have "bugs" or unforeseen problems which must be worked out before the superior characteristics of the new designs can be enjoyed. Thus there is a chance for a superior product, but only at higher risk.It should be emphasized that,if a design does not warrant radical new methods, such methods should not be applied merely for the sake of change.During the beginning stages of design, creativity should be allowed to flourish without a great number of constraints.Even though many impractical ideas may arise, it is usually easy to eliminate them in the earlystages of design before firm details are required by manufac-turing. In this way, innovative ideas are not inhibited. Quite often, more than one design is developed, up to the point where they can be compared against each other.It is entirely possible that the design which is ultimately accepted will use ideas existing in one of the rejected designs that did not show as much overall promise.Psychologists frequently talk about trying to fit people to the machines they operate. It is essentially the responsibility of the design engineer to strive to fit machines to people. This is not an easy task, since there is really no average person for which certain operating dimensions and procedures are optimum.Another important point which should be recognized is that a design engineer must be able to communicate ideas to other people if they are to be incorporated. Communicating the design to others is the final, vital step in the design process. Undoubtedly many great designs, inventions, and creative works have been lost to mankind simply because the originators were unable or unwilling to explain their accomplishments to others. Presentation is a selling job. The engineer, when presenting a new solution to administrative, management, or supervisory persons, is attempting to sell or to prove to them that this solution is a better one. Unless this can be done successfully, the time and effort spent on obtaining the solution have been largely wasted.Basically, there are only three means of communication available to us. Theseare the written, the oral, and the graphical forms. Therefore the successful engineer will be technically competent and versatile in all three forms of communication. A technically competent person who lacks ability in any one of these forms is severely handicapped.If ability in all three forms is lacking, no one will ever know how competent that person is!The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, occasional failure should be expected because failure or criticism seems to accompany every really creative idea. There is a great deal to be learned from a failure,and the greatest gains are obtained by those willing to risk defeat. In the final analysis, the real failure would lie in deciding not to make the presentation at all. To communicate effectively, the following questions must be answered:(1) Does the design really serve a human need?(2) Will it be competitive with existing products of rival companies?(3) Is it economical to produce?(4) Can it be readily maintained?(5) Will it sell and make a profit?Only time will provide the true answers to the preceding questions, but the product should be designed, manufactured and marketed only with initial affirmative answers. The design engineer also must communicate the finalized design to manufacturing through the use of detail and assembly drawings.Quite often, a problem will occur during the manufacturing cycle[3]. It may be that a change is required in the dimensioning or tolerancing of a part so that it can be more readily produced. This fails in the category of engineering changes which must be approved by the design engineer so that the product functionwill not be adversely affected. In other cases, a deficiency in the design may appear during assembly or testing just prior to shipping. These realities simply bear out the fact that design is a living process. There is always a better way to do it and the designer should constantly strive towards finding that better way.Designing starts with a need,real or imagined.Existing apparatus may need improvements in durability, efficiently, weight, speed, or cost. New apparatus maybe needed to perform a function previously done by men, such as computation, assembly, or servicing. With the obj ective wholly or partly defined, the next step in design is the conception of mechanisms and their arrangements that will perform the needed functions.For this, freehand sketching is of great value, not only as a record of one's thoughts and as an aid in discussion with others, but particularly for communication with one's own mind, as a stimulant for creative ideas. to fluctuating stress, particular attention is given to a reduction in stress concentration, and to an increase of strength at fillets, threads, holes, and fits. Stress reduction are made by modification in shape, and strengthening may be done by prestressing treatments such as surface rolling and shallow hardening. Hollow shafts and tubing, and box sections give a favorable stress distribution, together with stiffness and minimum weight. Sufficient stiffness to maintain alignment and uniform pressure between contacting surfaces should be provided for crank, cam, and gear shafts, and for enclosures and frames containing bearing supports. The stiffness of shafts and other components must be suitable to avoid resonant vibrations.e &zsic equations to calculate and optimize dimensions.The fundamental equations of mechanics and the other sciences are the accepted bases for calculations. They are sometimes rearranged in special forms to facilitate the determination or optimization of dimensions, such as the beam and surface stress equations for determining gear-tooth size. Factors may be added to a fundamental equation for conditions not analytically determinable, e. g. , on thin steel tubes, an allowance for corrosion added to the thickness based on pressure. When it is necessary to apply a fundamental equation to shapes, materials, or conditions which only approximate the assumptions for its derivation, it is done in a manner which gives results "on the safe side".In situations where data are incomplete, equations of the sciences may be used as proportioning guides to extend a satisfactory design to new capacities.4.Choose materials for a combination of properties.Materials should be chosen fora combination of pertinent properties, not only for strengths, hardness, and weight, but sometimes for resistance to impact, corrosion, and low or high temperatures. Cost and fabrication properties are factors, such as weldability, machinability, sensitivity to variation in heat-treating temperatures, and required coating.5.Select carefully between stock and integral components. A previously developed components is frequently selected by a designer and his company from the stocks of parts manufacturers, if the component meet the performance and reliability requirements and is adaptable without additional development costs to the particular machine being designed.However, its selection should be carefully made wi'th a full knowledge of its propcrties, since the reputation and liability of the company suffer if there is a failure in any one of the machine's parts. In other eases the strength, reliability, and cost requirements are better met if the designer of the machine also designs the component, with the particular advantage of compactness if it is designs integral with other components, e. g., gears to be forged in clusters or integral with a shaft.6. Provide for accurate location and non interference of parts in assembly. A good design provides for the correct locating of parts and for easy assembly and repair.Shoulders and pilot surfaces give accurate location without measurement during assembly. Shapes can be designed so that parts cannot be assembled backwards or in the wrong place. Interferences, as between screws in tapped holes, and between linkages must he foreseen and prevended.Inaccurate alignment and positioning between such assemblies must be avoided, or provision must be made to minimize any resulting detrimental displacements and stresses.The human race has distinguished itself from all other forms of life by using tools and intelligence to create items that serve to make life easier and more enjoyable. Through the centuries, both the tools and theenergy sources to power these tools have evolved to meet the increasing sophistication and complexity ofmankind's ideas.In their earliest forms, tools primarily consisted of stone instruments. Considering tile relative simplicity of the items being made and the materials being shaped, stone was adequate. When iron tools were invented, durable metals and more sophisticated articles could be produced. The twentieth century has seen the creation of products made from the most durable and,consequently, the most unmachinable materials in history. In an effort to meet the manufacturing challenges created by these materials, tools have now evolved to include materials such as alloy steel, carbide, diamond, and ceramics.A similar evolution has taken place with the methods used to power our tools. Initially,tools were powered by muscles; either human or animal. However as the powers of water, wind, steam, and electricity were harnessed, mankind was able tofurther extended manufacturing capabilities with new machines, greater accuracy, and faster machining rates.Every time new tools, tool materials, and power sources are utilized, the efficiency and capabilities of manufacturers are greatly enhanced. However as old problems are solved, new problems and challenges arise so that the manufacturers of today are faced with tough questions such as the following: How do you drill a 2 mm diameter hole 670 mm deep without experiencing taper or runout? Is there a way to efficiently deburr passageways inside complex castings and guarantee 100 % that no burrs were missed? Is there a welding process that can eliminate the thermal damage now occurring to my product?Since the 1940s, a revolution in manufacturing has been taking place that once again allows manufacturers to meet the demands imposed by increasingly sophisticated designs and durable, but in many cases nearly unmachinable, materials. This manufacturing revolution is now, as it has been in the past, centered on the use of new tools and new forms of energy.The result has been the introduction of new manufacturing processes used for material removal, forming, and joining, known today as nontraditional manufacturing processes.The conventional manufacturing processes in use today for material removal primarily rely on electric motors and hard tool materials to perform tasks such as sawing, drilling, an broaching. Conventional forming operations are performed with the energy from electric motors, hydraulics, and gravity. Likewise, material joining is conventionally accomplished with thermal energy sources such as burning gases and electric arcs.In contrast, nontraditional manufacturing processes harness energy sources considered unconventional by yesterday's standards. Material removal can now be accomplished with electrochemical reactions, high-temperature plasmas, and high-velocity jets of liquids and abrasives. Materials that in the past have been extremely difficult to form, are now formed with magnetic fields, explosives, and the shock waves from powerful electric sparks. Material-joining capabilities have been expanded with the use of high-frequency sound waves and beams of electrons.In the past 50 years, over 20 different nontraditional manufacturing processes have been invented andsuccessfully implemented into production. The reason there are such a large number of nontraditional processes is the same reason there aresuch a large number of conventional processes; each process has its own characteristic attributes and limitations, hence no one process is best for all manufacturing situations.For example, nontraditional process are sometimes applied to increase productivity either by reducing the number of overall manufacturing operations required to produce a product or by performing operations faster than the previously used method.In other cases, nontraditional processes are used to reduce the number of rejects experienced by the old manufacturing method by increasing repeatability, reducing in-process breakage of fragile workpieces, or by minimizing detrimental effects on workpiece properties.Because of the aforementioned attributes, nontraditional manufacturing processes have experienced steady growth since their introduction. An increasing growth rate for these processes in the future is assured for the following reasons:1.Currently, nontraditional processes possess virtually unlimited capabilities when compared with conventional processes, except for volumetric material removal rates. Great advances have been made in the past few years in increasing the removal rates of some of these processes, and there is no reason to believe that this trend will not continue into the future.2. Approximately one half of the nontraditional manufacturing processes are available with computer control of the process parameters. The use of computers lends simplicity to processes that people may be unfamiliar with, and thereby accelerates acceptance.Additionally, computer control assures reliability and repeatability[s], which also accelerates acceptance and implementation.3.Most nontraditional processes are capable of being adaptively-controlled through the use of vision systems, laser gages, and other in-process inspection techniques. If, for example, the in-process inspection system determines that the size of holes being produced in a product are becoming smaller, the size can be modified without changing hard tools, such as drills.4.The implementation of nontraditional manufacturing processes will continus to increase as manufacturing engineers, product designers, and metallurgical engineers become increasingly aware of the unique capabilties and benefits that nontraditional manufacturing processes provide.The high speed milling processing is more and more high to the numericalcontrol programming system request, the price expensive high speed processing equipment proposed a higher secure and the valid request to the software. The high-speed cutting has compared to the traditional cutting special technological requirement, besides must have the high-speed cutting engine bed and the high-speed cutting cutting tool, has the appropriate CAM programming software also is very important. The numerical control processing numerical control instruction has contained all technological process, outstanding high speed processes the CAM programming system to be supposed to have the very high computation speed, strong inserts makes up the function, the entire journey is automatic has cut the inspection and the handling ability, the automatic hilt and the jig interference inspection, enters for rate the optimized processing function, treats the processing path monitoring function, the cutting tool path edition optimization function and the processing remaining analysis function and so on. The high-speed cutting programming first must pay attention to the processing method the security and the validity; Next, must guarantee with utmost effort the cutting tool path smooth is steady, this can affect components the directly and so on processing quality and engine bed main axle life; Finally, must cause the cutting tool load to be even as far as possible, this can affect the cutting tool directly the life.1. The CAM system should have the very high computation programming speedIn the high speed processing uses extremely small entering and cuts the depth for the quantity, its NC procedure must be much bigger than to the traditional numerical control processing procedure, thus requests the software computation speed to have to be quick, by saves the cutting tool path edition and the optimized programming time.2. The entire journey automatically guards against has cut the handling ability and the automatic hilt interference inspection abilityThe high speed processing processes the nearly 10 time of cuttings speeds by the tradition to carry on the processing, once will occur has cut to the engine bed, the product and the cutting tool has the calamity consequence, therefore will request its CAM system to have to have the entire journey automatically to guard against has cut processing the ability and the automatic hilt and the jig interference inspection, circles evades the function. The system can automatically prompt short supports on both sides the cutting tool length, and automatically carries on the cutting tool interference inspection.3. Rich high-speed cutting cutting tool path strategyThe high speed processing to processes the craft to feed the way to have the special request compared to the traditional way, in order to can guarantee the maximum cutting efficiency, also guaranteed when high-speed cutting processes the security, the CAM system ought to be able to act according to processes the instantaneous remainder the size automatically to enter for rate carries on optimized processing, can automatically carry on the cutting tool path edition to optimize, the processing remaining analysis and the treatment processing path monitoring, by guarantees the high speed processing cutting tool stressful condition the stability, enhances the cutting tool the service life.After uses the high speed processing equipment, will be able to increase to programmers' demand, because high speed will process the technological requirement strictly, has cut the protection to be more important, therefore will have to spend the much time to carry on the simulation examination to the NC instruction. In the ordinary circumstances, high speed processes the programming time the to be ordinary than processing programming time to have to be much longer. In order to guarantee the high speed processing equipment enough utilization ratio, must dispose the more CAM personnel. The existing CAM software, like PowerMILL, MasterCAM, UnigraphicsNX, Cimatron and so on have all provided the correlation function high speed milling cutting tool path strategy.中文译文：机械设计及加工工艺机械设计是一门通过设计新产品或者改进老产品，满足人类需求的应用技术科学。
机械制造专业外文翻译--锻造
英文原文：A.1 FORGINGBulk defirnnation of metals refers to various processes, such as forging, rolling, or extruding, where there is a controlled plastic flow or working of metals into useful shapes. The most well known of these processes is forging where deformation is accomplished by means of pressure, impact blows, or a combination of both.Hammer ForgingHanuner forging consists of striking the hot metal with a large semiautomatic hammer. If no dies are involved, the forging will be dependent mainly on the skill of the operator. If closed or impression dies are used, one blow is struck for each of several (lie cavities. A- gain, productivity and quality depend to a large degree on the skill of the hanimer operator and the tooling.Press ForgingPress forging is characterized by a slow squeezing action. Again, open or closed dies may be used. The open dies are used chiefly for large, simple-geometry parts that are later machined to shape. Closed-die forging relies less on operator skill awl more on the design of the preform and forging dies.2 As an example of the versatility of the process, newer developments have made it possible to produce bevel gears with straight or helical teeth. Rotation of the die (luring penetration will press bevel gears with spiral teeth.Open-die ForgingOpen-die forging is distinguished by the fact that the metal is never completely confined as it is shaped by various dies. Most open-die forgings are produced on flat, V, or swaging dies. Round swaging (lies and V dies are used in pairs or with a flat die. The top (lie is attached to the ram of the press, and the bottom die is attached to the hammer anvil or, in the case of press open-die forging, to the press bed.As the workpiece is hammered or pressed, it is repeatedly manipulated between the dies until hot working forces the metal to the final dimensions, as-shown in Fig. 1. After forging, the part is rough- and finished-machined. As an example of the amount of material allowed for machining, a 6.5 in. diameter shaft would have to be forged to 7.4 in. dianieter.In open-die forging of steel, a rule of thumb says that 50 lb of falling weight is required for each square inch of cross section.Impression-die ForgingIn the simplest example of impression-die forging, two dies are brought together, and the workpiece undergoes plastic deformation until its enlarged sides touch the side walls of the die (Fig. 2). A small amount of material is forced outside the die impression, forming flash that is gradually thinned. The flash cools rapidly and presents increased resistance to deformation, effectively becoming a part of the tool, and helps build up l)ressUre inside the bulk of the work- piece that aids material flow into unfilled impressions.Closed-die forgings, a special form of impression-die forging, does not depend on theformation of flash to achieve complete filling of the (lie. Thus closed-die forging is considerably more demanding on die design. Since pressing is often completed in one stroke, careful control of the workpieee volume is necessaiy to achieve complete filling without generating extreme pressures in the dies from overfilling.Extrusion ForgingAs with upsetting, extrusion forging is often accomplished by cold working. Three principal types of metal displacement by plastic flow are involved. Backward and forward, tube, and impact extrusion are shown in Fig. 3. The metal is placed in a container and corn- pressed by a ram movement until pressure inside the metal reaches flow-stress levels. The workpiece completely fills the container, and additional pressure causes it to leave through an orifice and form the extruded product.Extruded products may be either solid or hollow shapes. Tube extrusion is used to produce hollow shapes such as containers and pipes. Reverse-impact extrusion is used for mass production of aluminum cans. The ram hits a slug of metal in the die at high impact, usually 15 times the yield strength of the metal, which causes it to flow instantaneously up the walls of the die. Other common hollow extrusion products are aerosol cans, lipstick cases, flashlight cases, and vacuum bottles. Secondary operations, such as heading, thread rolling, dimpling, and machining, are often needed to complete the items.Generally steel impacts are limited to 2.5 times the punch diameter. Hydraulic presses areused for loads of over 2000 tons because they have a greater variation in stroke length, speed,and other economic advantages. Tolerances vary with materials arid design, hut productionruns calling for 0.002- to 0.005-in, tolerance are regularly made.Roll ForgingRoll forging in its simplest form consists of a heated billet passing between a pair of rollsthat deform it along its length (Fig. 8-4). Compared to conventional rolling processes, therolls are relatively small in diameter and serve as an arbor into which the forging tools aresecured. The active surface of the tool occupies only a portion (usually half) of the rollcircumference to accommodate the full cross section of the stock.The reduction of the cross section obtainable in one pass is limited by the tendency of thematerial to spread and form an undesirable flash that may be forged into the surface as a90rota- defect in the subsequent operations. The workpiece is int roduced repeatedly withtion between passes.Ring RollingRing rolling offers a homogeneous circumferential grain flow, ease of fabrication andmachining, and versatility of material size . Manu- facture of a rolled ring starts with asheared blank, which is forged to a pancake, punched, and pierced.There is no limit to the size of the rolled rings, ranging from roller-bearing sleeves to Fig.4 Roll forging rings 25 ft in diameter with face heights of 80 in. Various profiles may berolled by suitably shaping the driven, idling rolls.CAD/CAM in ForgingCAD/CAM is being increasingly applied to frging. Using the three-dimensional description of a machined part, which may have been computer designed, it is possible to generate the geometry of the associated forging. Thus the forging sections can be obtained from a common (laiR base. Using well-known techniques, forging loads and stresses can be obtained and flash dimensions can be selected for each section where metal flow is approximated as ro dimensional (plane strain or axisymmetric ). In some relatively simple section geomethes, computer simulation can be conducted to evaluate initial guesses on preform sections. Once the preform geometry has been developed to the designer¡¯s satisfaction, this geometric data base can utilized to write NC part programs to obtain the NC tapes or disks for machining.A.2 HEAT TREATMENT OF METALAnnealingThe word anneal has been used before to describe heat-treating processes for softening and regaining ductility in connection with cold working of material. It has a similar meaning when used in connection with the heat treating of allotropic materials. The purpose of full annealing is to decrease hardness, increase ductility, and sometimes improve machinability of high carbon steels that might otherwise be difflcult to cut. The treatment is also used to relieve stresses, refine grain size, and promote uniformity of structure throughout the material.Machinability is not always improved by annealing. The word machinability is used to describe several interrelated factors, including the ability of a material to be cut with a good surface finish. Plain low carbon steels, when fully annealed, are soft and relatively weak, offering little resistance to cutting, but usually having sufficient ductility and toughness that a cut chip tends to puli and tear the surface from which it is removed, leaving a comparatively poor quality surface, which results in a poor machinability rating. For such steels annealing may not be the most suitable treatment. The machinability of many of the higher plain carbon and most of the alloy steels can usually be greatly improved by annealing, as they are often too hard and strong to be easily cut at any but their softest condition .The procedure for annealing hypoeutectoid steel is to heat slowly to approximately 60C︒above the Ac3 line, to soak for a long enough period that the temperature equalizes throughout the material and homogeneous austenite is formed, and then to allow the steel to cool very slowly by cooling it in the furnace or burying it in lime or some other insulating material. The slow cooling is essential to the precipitation of the maximum ferrite and the coarsest pearlite to place the steel in its softest, most ductile, and least strained condition. NormalizingThe purpose of normalizing is somewhat similar to that of annealing with the exceptions that the steel is not reduced to its softest condition and the pearlite is left rather fine instead of coarse. Refinement of grain size, relief of internal stresses, and improvement of structural uniformity together with recovery of some ductility provide high toughness qualities in normalized steel. The process is frequently used for improvement of machinability and for stress nlief to reduce distortion that might occur with partial machining or aging.The procedure for normalizing is to austenitize by slowly heating to approximately80above the Ac3 or Accm3 temperature for hypoeutectoid or hypereuteetoid steels, C︒respectively; providing soaking time for the formation of austenite; and cooling slowly in still air. Note that the steels with more carbon than the eutectoid composition are heated above the Aom instead of the Ac used for annealing. The purpose of normalizing is to attempt to dissolve all the cementite during austenitization to eliminate, as far as possible, the settling of hani, brittle iron carbide in the grain boundaries. The desired decomposition products are smallgrained, fine pearlite with a minimum of free ferrite and free cementite. SpheroidizingMinimum hardness and maximum ductility of steel can he produced by a process called spheroidizing, which causes the iron carbide to form in small spheres or nodules in a ferrite matrix, in order to start with small grains that spheroid ize more readily, the process is usually performed on normalized steel. Several variations of processing am used, but all reqllin the holding of the steel near the A1 temperature (usually slightly below) for a number of hours to allow the iron carbide to form on its more stable and lower energy state of small, rounded glohules.The main need for the process is to improve the machinability quality of high carbonsteel and to pretreat hardened steel to help produce greater structural uniformity after quenching. Because of the lengthy treatment time and therefore rather high cost, spheroidizing is not performed nearly as much as annealing or normalizing.Hardening of SteelMost of the heat treatment hardening processes for steel are basel on the production of high pereentages of martensite. The first step. therefore, is that used for most of the other heat-treating processes-treatment to produce austenite. Hypoeutectoid steels are heated to approximately 60CC above the Ac3 temperature and allowed to soak to obtain temperature unifonnity and austenite homogeneity. Hypereutectoid steels are soaked at about 60CC above the A1 temperature, which leaves some iron carbide present in the material.The second step involves cooling rapidly in an attempt to avoid pearlite transformation by missing the nose of the i-T curve. The cooling rate is determined by the temperature and the ability of the quenching media to carry heat away from the surface of the material being quenched and by the conduction of heat through the material itself. Table1 shows some of the commonly used media and the method of application to remove heat, arranged in order of decreasing cooling ability.High temperature gradients contribute to high stresses that cause distortion and cracklug, so the quench should only as extreme as is necessary to produce the desired structure. Care must be exercised in quenching that heat is removed uniformly to minimize thermal stresses.For example, a long slender bar should be end-quenched, that is, inserted into the quenching medium vertically so that the entire section is subjected to temperature change at one time. if a shape of this kind were to be quenched in a way that caused one side to drop in temperature before the other, change of dimensions would likely cause high stresses producing plastic flow and permanent distortion.Several special types of quench are conducted to minimize quenching stresses and decrease the tendency for distortion and cracking. One of these is called martempering and consists of quenching an austenitized steel in a salt at a temperature above that needed for the start of martensite formation (Ms). The steel being quenched is held in this bath until it is of uniform temperature but is removed before there is time for fonnation of bainite to start. Completion of the cooling in air then causes the same hard martensite that would have formed with quenching from the high temperature, but the high thermal or ¡°quench¡± stresses that are the primary source of cracks and warping will have been eliminated.A similar process performed at a slightly higher temperature is called austempering. In this case the steel is held at the bath temperarnre for a longer period, and the result of the isothermal treatment is the formation of bainite. The bainite structure is not as hard as the martensite that could be formed from the same composition, but in addition to reducing the thermal shock to which the steel would be subjected under normal hardening procedures, ii is unnecessary to perform any further treatment to develop good impact resistance in the high hardness rangeTemperingA third step usually required to condition a hardened steel for service is tempering, or as it is sometimes referred to, drawing. With the exception of austempered steel, which is frequently used in the as-hardened condition, most steels are not serviceable “as quenched”. The drastic cooling to produce martensite causes the steel to be very hard and to contain both macroscopic and microscopic internal stresses with the result that the material has little ductility and extreme brittleness. Reduction of these faults is accomplished by reheating the steel to some point below the A1 (lower transformation) temperature. The stnictural changes caused by tempering of hardened steel are functions of both time and temperature, with temperature being the most important. It should be emphasized that tempering is not ahardening process, but is, instead, the reverse. A tempered steel is one that has been hardened by heat treatment and then stress relieved, softened, and provided with increased ductility by reheating in the tempering or drawing procedure.The magnitude of the structural changes and the change of properties caused by tempering depend upon the temperature to which the steel is reheated. The higher the ternperatun, the greater the effect, so the choice of temperature will generally depend on willingness to sacrifice hardness and strength to gain ductility and toughness. Reheating to below lOOt has little noticeable effect on hardened plain carbon steel. Between lO(YC and 200T, there is evidence of some structural changes. Above 200T marked changes in structure and properties appear. Prolonged heating at just under the A1 temperature will result in a spheroidized structure similar to that produced by the spheroidizing process.In commercial tempering the temperature range of 25O-425 is usually avoided because of an unexplained embrittlement, or loss of ductility, that often occun with steels ternpered in this range. Certain alloy steels also develop a ¡°temper brittleness¡± in the tempera- ture range of 425-600C︒, particularly when cooled slowly from or through this range of temperature. When high temperature tempering is necessary for these steels, they are usually heated to above 600C︒and quenched for rapid cooling. Quenches from this temperature, of course, do not cause hardening because austenitization has not been accomplished.中文译文：B.1 锻造金属变形方法有多种，比如通过锻造、滚压或挤压，使金属的塑性流动或加工受到控制而得到有用的形状。
机械专业外文翻译中英文翻译外文文献翻译
英文资料High-speed millingHigh-speed machining is an advanced manufacturing technology, different from the traditional processing methods. The spindle speed, cutting feed rate, cutting a small amount of units within the time of removal of material has increased three to six times. With high efficiency, high precision and high quality surface as the basic characteristics of the automobile industry, aerospace, mold manufacturing and instrumentation industry, such as access to a wide range of applications, has made significant economic benefits, is the contemporary importance of advanced manufacturing technology. For a long time, people die on the processing has been using a grinding or milling EDM (EDM) processing, grinding, polishing methods. Although the high hardness of the EDM machine parts, but the lower the productivity of its application is limited. With the development of high-speed processing technology, used to replace high-speed cutting, grinding and polishing process to die processing has become possible. To shorten the processing cycle, processing and reliable quality assurance, lower processing costs.1 One of the advantages of high-speed machiningHigh-speed machining as a die-efficient manufacturing, high-quality, low power consumption in an advanced manufacturing technology. In conventional machining in a series of problems has plagued by high-speed machining of the application have been resolved.1.1 Increase productivityHigh-speed cutting of the spindle speed, feed rate compared withtraditional machining, in the nature of the leap, the metal removal rate increased 30 percent to 40 percent, cutting force reduced by 30 percent, the cutting tool life increased by 70% . Hardened parts can be processed, a fixture in many parts to be completed rough, semi-finishing and fine, and all other processes, the complex can reach parts of the surface quality requirements, thus increasing the processing productivity and competitiveness of products in the market.1.2 Improve processing accuracy and surface qualityHigh-speed machines generally have high rigidity and precision, and other characteristics, processing, cutting the depth of small, fast and feed, cutting force low, the workpiece to reduce heat distortion, and high precision machining, surface roughness small. Milling will be no high-speed processing and milling marks the surface so that the parts greatly enhance the quality of the surface. Processing Aluminum when up Ra0.40.6um, pieces of steel processing at up to Ra0.2 ~ 0.4um.1.3 Cutting reduce the heatBecause the main axis milling machine high-speed rotation, cutting a shallow cutting, and feed very quickly, and the blade length of the workpiece contacts and contact time is very short, a decrease of blades and parts of the heat conduction. High-speed cutting by dry milling or oil cooked up absolute (mist) lubrication system, to avoid the traditional processing tool in contact with the workpiece and a lot of shortcomings to ensure that the tool is not high temperature under the conditions of work, extended tool life.1.4 This is conducive to processing thin-walled partsHigh-speed cutting of small cutting force, a higher degree of stability, Machinable with high-quality employees compared to the company may be very good, but other than the company's employees may Suanbu Le outstanding work performance. For our China practice, we use the models to determine the method of staff training needs are simple and effective. This study models can be an external object, it can also be a combination of internal and external. We must first clear strategy for the development of enterprises. Through the internal and external business environment and organizational resources, such as analysis, the future development of a clear business goals and operational priorities. According to the business development strategy can be compared to find the business models, through a comparative analysis of the finalization of business models. In determining business models, a, is the understanding of its development strategy, or its market share and market growth rate, or the staff of the situation, and so on, according to the companies to determine the actual situation. As enterprises in different period of development, its focus is different, which means that enterprises need to invest the manpower and financial resources the focus is different. So in a certain period of time, enterprises should accurately selected their business models compared with the departments and posts, so more practical significance, because the business models are not always good, but to compare some aspects did not have much practical significance, Furthermore This can more fully concentrate on the business use of limited resources. Identify business models, and then take the enterprise of the corresponding departments and staff with the business models for comparison, the two can be found in the performance gap, a comparative analysis to find reasons, in accordance with this business reality, the final identification of training needs. The cost of training is needed, if not through an effective way to determine whether companies need to train and the training of the way, but blind to training, such training is difficult to achieve the desired results. A comparison only difference between this model is simple and practical training.1.5 Can be part of some alternative technology, such as EDM, grinding high intensity and high hardness processingHigh-speed cutting a major feature of high-speed cutting machine has the hardness of HRC60 parts. With the use of coated carbide cutter mold processing, directly to the installation of ahardened tool steel processing forming, effectively avoid the installation of several parts of the fixture error and improve the parts of the geometric location accuracy. In the mold of traditional processing, heat treatment hardening of the workpiece required EDM, high-speed machining replace the traditional method of cutting the processing, manufacturing process possible to omit die in EDM, simplifying the processing technology and investment costs .High-speed milling in the precincts of CNC machine tools, or for processing centre, also in the installation of high-speed spindle on the general machine tools. The latter not only has the processing capacity of general machine tools, but also for high-speed milling, a decrease of investment in equipment, machine tools increased flexibility. Cutting high-speed processing can improve the efficiency, quality improvement, streamline processes, investment and machine tool investment and maintenance costs rise, but comprehensive, can significantly increase economic efficiency.2 High-speed millingHigh-speed milling the main technical high-speed cutting technology is cutting the development direction of one of it with CNC technology, microelectronic technology, new materials and new technology, such as technology development to a higher level. High-speed machine tools and high-speed tool to achieve high-speed cutting is the prerequisite and basic conditions, in high-speed machining in the performance of high-speed machine tool material of choice and there are strict requirements.2.1 High-speed milling machine in order to achieve high-speed machiningGeneral use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas:General use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas:High-speed milling machine must have a high-speed spindle, the spindle speed is generally 10000 ~ 100000 m / min, power greater than 15 kW. But also with rapid speed or in designated spots fast-stopping performance. The main axial space not more than 0 .0 0 0 2 m m. Often using high-speed spindle-hydrostatic bearings, air pressure-bearing, mixed ceramic bearings, magneticbearing structure of the form. Spindle cooling general use within the water or air cooled.High-speed processing machine-driven system should be able to provide 40 ~ 60 m / min of the feed rate, with good acceleration characteristics, can provide 0.4 m/s2 to 10 m/s2 acceleration and deceleration. In order to obtain good processing quality, high-speed cutting machines must have a high enough stiffness. Machine bed material used gray iron, can also add a high-damping base of concrete, to prevent cutting tool chatter affect the quality of processing. A high-speed data transfer rate, can automatically increase slowdown. Processing technology to improve the processing and cutting tool life. At present high-speed machine tool manufacturers, usually in the general machine tools on low speed, the feed of the rough and then proceed to heat treatment, the last in the high-speed machine on the half-finished and finished, in improving the accuracy and efficiency at the same time, as far as possible to reduce processing Cost.2.2 High-speed machining toolHigh-speed machining tool is the most active one of the important factors, it has a direct impact on the efficiency of processing, manufacturing costs and product processing and accuracy. Tool in high-speed processing to bear high temperature, high pressure, friction, shock and vibration, such as loading, its hardness and wear-resistance, strength and toughness, heat resistance, technology and economic performance of the basic high-speed processing performance is the key One of the factors. High-speed cutting tool technology development speed, the more applications such as diamond (PCD), cubic boron nitride (CBN), ceramic knives, carbide coating, (C) titanium nitride Carbide TIC (N) And so on. CBN has high hardness, abrasion resistance and the extremely good thermal conductivity, and iron group elements between the great inertia, in 1300 ℃ would not have happened significant role in the chemical, also has a good stability. The experiments show that with CBN cutting toolHRC35 ~ 67 hardness of hardened steel can achieve very high speed. Ceramics have good wear resistance and thermal chemical stability, its hardness, toughness below the CBN, can be used for processing hardness of HRC <5 0 parts. Carbide Tool good wear resistance, but the hardness than the low-CBN and ceramics. Coating technology used knives, cutting tools can improve hardness and cutting the rate, for cutting HRC40 ~ 50 in hardness between the workpiece. Can be used to heat-resistant alloys, titanium alloys, hightemperature alloy, cast iron, Chungang, aluminum and composite materials of high-speed cutting Cut, the most widely used. Precision machining non-ferrous metals or non-metallic materials, or the choice of polycrystalline diamond Gang-coated tool.2.3 High-speed processing technologyHigh-speed cutting technology for high-speed machining is the key. Cutting Methods misconduct, will increase wear tool to less than high-speed processing purposes. Only high-speed machine tool and not a good guide technology, high-speed machining equipment can not fullyplay its role. In high-speed machining, should be chosen with milling, when the milling cutter involvement with the workpiece chip thickness as the greatest, and then gradually decreased. High-speed machining suitable for shallow depth of cut, cutting depth of not more than 0.2 mm, to avoid the location of deviation tool to ensure that the geometric precision machining parts. Ensure that the workpiece on the cutting constant load, to get good processing quality. Cutting a single high-speed milling path-cutting mode, try not to interrupt the process and cutting tool path, reducing the involvement tool to cut the number to be relatively stable cutting process. Tool to reduce the rapid change to, in other words when the NC machine tools must cease immediately, or Jiangsu, and then implement the next step. As the machine tool acceleration restrictions, easy to cause a waste of time, and exigency stop or radical move would damage the surface accuracy. In the mold of high-speed finishing, in each Cut, cut to the workpiece, the feed should try to change the direction of a curve or arc adapter, avoid a straight line adapter to maintain the smooth process of cutting.3 Die in high-speed milling processing ofMilling as a highly efficient high-speed cutting of the new method,inMould Manufacturing has been widely used. Forging links in the regular production model, with EDM cavity to be 12 ~ 15 h, electrodes produced 2 h. Milling after the switch to high-speed, high-speed milling cutter on the hardness of HRC 6 0 hardened tool steel processing. The forging die processing only 3 h20min, improve work efficiency four to five times the processing surface roughness of Ra0.5 ~ 0.6m, fully in line with quality requirements.High-speed cutting technology is cutting technology one of the major developments, mainly used in automobile industry and die industry, particularly in the processing complex surface, the workpiece itself or knives rigid requirements of the higher processing areas, is a range of advanced processing technology The integration, high efficiency and high quality for the people respected. It not only involves high-speed processing technology, but also including high-speed processing machine tools, numerical control system, high-speed cutting tools and CAD / CAM technology. Die-processing technology has been developed in the mold of the manufacturing sector in general, and in my application and the application of the standards have yet to be improved, because of its traditional processing with unparalleled advantages, the future will continue to be an inevitable development of processing technology Direction.4 Numerical control technology and equipping development trend and countermeasureEquip the engineering level, level of determining the whole national economy of the modernized degree and modernized degree of industry, numerical control technology is it develop new developing new high-tech industry and most advanced industry to equip (such as information technology and his industry, biotechnology and his industry, aviation, spaceflight, etc. national defense industry) last technology and getting more basic most equipment. Marx has ever said "the differences of different economic times, do not lie in what is produced, and lie in how to produce,produce with some means of labor ". Manufacturing technology and equipping the most basic means of production that are that the mankind produced the activity, and numerical control technology is nowadays advanced manufacturing technology and equips the most central technology. Nowadays the manufacturing industry all around the world adopts numerical control technology extensively, in order to improve manufacturing capacity and level, improve the adaptive capacity and competitive power to the changeable market of the trends. In addition every industrially developed country in the world also classifies the technology and numerical control equipment of numerical control as the strategic materials of the country, not merely take the great measure to develop one's own numerical control technology and industry, and implement blockading and restrictive policy to our country in view of " high-grade, precision and advanced key technology of numerical control " and equipping. In a word, develop the advanced manufacturing technology taking numerical control technology as the core and already become every world developed country and accelerate economic development in a more cost-effective manner, important way to improve the overall national strength and national position. Numerical control technology is the technology controlled to mechanical movement and working course with digital information, integrated products of electromechanics that the numerical control equipment is the new technology represented by numerical control technology forms to the manufacture industry of the tradition and infiltration of the new developing manufacturing industry, namely the so-called digitization is equipped, its technological range covers a lot of fields: (1)Mechanical manufacturing technology; (2)Information processing, processing, transmission technology; (3)Automatic control technology; (4)Servo drive technology;(5)Technology of the sensor; (6)Software engineering ,etc..Development trend of a numerical control technologyThe application of numerical control technology has not only brought the revolutionary change to manufacturing industry of the tradition, make the manufacturing industry become the industrialized symbol , and with the constant development of numerical control technology and enlargement of the application, the development of some important trades (IT , automobile , light industry , medical treatment ,etc. ) to the national economy and the people's livelihood of his plays a more and more important role, because the digitization that these trades needed to equip has already been the main trend of modern development. Numerical control technology in the world at present and equipping the development trend to see, there is the following several respect [1- ] in its main research focus.5 A high-speed, high finish machining technology and new trend equippedThe efficiency, quality are subjavanufacturing technology. High-speed, high finish machining technology can raise the efficiency greatly , improve the quality and grade of the products, shorten production cycle and improve the market competitive power. Japan carries the technological research association first to classify it as one of the 5 great modern manufacturing technologies forthis, learn (CIRP) to confirm it as the centre in the 21st century and study one of the directions in international production engineering.In the field of car industry, produce one second when beat such as production of 300,000 / vehicle per year, and many variety process it is car that equip key problem that must be solved one of; In the fields of aviation and aerospace industry, spare parts of its processing are mostly the thin wall and thin muscle, rigidity is very bad, the material is aluminium or aluminium alloy, only in a situation that cut the speed and cut strength very small high, could process these muscles, walls. Adopt large-scale whole aluminium alloy method that blank " pay empty " make the wing recently, such large-scale parts as the fuselage ,etc. come to substitute a lot of parts to assemble through numerous rivet , screw and other connection way, make the intensity , rigidity and dependability of the component improved. All these, to processing and equipping the demand which has proposed high-speed, high precise and high flexibility.According to EMO2001 exhibition situation, high-speed machining center is it give speed can reach 80m/min is even high , air transport competent speed can up to 100m/min to be about to enter. A lot of automobile factories in the world at present, including Shanghai General Motors Corporation of our country, have already adopted and substituted and made the lathe up with the production line part that the high-speed machining center makes up. HyperMach lathe of U.S.A. CINCINNATI Company enters to nearly biggest 60m/min of speed, it is 100m/min to be fast, the acceleration reaches 2g, the rotational speed of the main shaft has already reached 60 000r/min. Processing a thin wall of plane parts, spend 30min only, and same part general at a high speed milling machine process and take 3h, the ordinary milling machine is being processed to need 8h; The speed and acceleration of main shaft of dual main shaft lathes of Germany DMG Company are up to 120000r/mm and 1g.In machining accuracy, the past 10 years, ordinary progression accuse of machining accuracy of lathe bring 5μm up to from 10μm already, accurate grades of machining center from 3～5μm, rise to 1～1.5μm, and ultraprecision machining accuracy is i t enter nanometer grade to begin already (0.01μm).In dependability, MTBF value of the foreign numerical control device has already reached above 6 000h, MTBF value of the servo system reaches above 30000h, demonstrate very high dependability .In order to realize high-speed, high finish machining, if the part of function related to it is electric main shaft, straight line electrical machinery get fast development, the application is expanded further .5.2 Link and process and compound to process the fast development of the lathe in 5 axesAdopt 5 axles to link the processing of the three-dimensional curved surface part, can cut with the best geometry form of the cutter , not only highly polished, but also efficiency improves by a large margin . It is generally acknowledged, the efficiency of an 5 axle gear beds can equal 2 3 axle gearbeds, is it wait for to use the cubic nitrogen boron the milling cutter of ultra hard material is milled and pared at a high speed while quenching the hard steel part, 5 axles link and process 3 constant axles to link and process and give play to higher benefit. Because such reasons as complicated that 5 axles link the numerical control system , host computer structure that but go over, it is several times higher that its price links the numerical control lathe than 3 axles , in addition the technological degree of difficulty of programming is relatively great, have restricted the development of 5 axle gear beds.At present because of electric appearance of main shaft, is it realize 5 axle complex main shaft hair structure processed to link greatly simplify to make, it makes degree of difficulty and reducing by a large margin of the cost, the price disparity of the numerical control system shrinks. So promoted 5 axle gear beds of head of complex main shaft and compound to process the development of the lathe (process the lathe including 5).At EMO2001 exhibition, new Japanese 5 of worker machine process lathe adopt complex main shaft hair, can realize the processing of 4 vertical planes and processing of the wanton angle, make 5 times process and 5 axles are processed and can be realized on the same lathe, can also realize the inclined plane and pour the processing of the hole of awls. Germany DMG Company exhibits the DMUVoution series machining center, but put and insert and put processing and 5 axles 5 times to link and process in once, can be controlled by CNC system or CAD/CAM is controlled directly or indirectly.5.3 Become the main trend of systematic development of contemporary numerical control intelligently, openly, networkedly.The numerical control equipment in the 21st century will be sure the intelligent system, the intelligent content includes all respects in the numerical control system: It is intelligent in order to pursue the efficiency of processing and process quality, control such as the self-adaptation of the processing course, the craft parameter is produced automatically; Join the convenient one in order to improve the performance of urging and use intelligently, if feedforward control , adaptive operation , electrical machinery of parameter , discern load select models , since exactly makes etc. automatically; The ones that simplified programming , simplified operating aspect are intelligent, for instance intelligent automatic programming , intelligent man-machine interface ,etc.; There are content of intelligence diagnose , intelligent monitoring , diagnosis convenient to be systematic and maintaining ,etc..Produce the existing problem for the industrialization of solving the traditional numerical control system sealing and numerical control application software. A lot of countries carry on research to the open numerical control system at present, such as NGC of U.S.A. (The Next Generation Work-Station/Machine Control), OSACA of European Community (Open System Architecture for Control within Automation Systems), OSEC (Open System Environment for Controller) of Japan, ONC (Open Numerical Control System) of China, etc.. The numerical control system melts tobecome the future way of the numerical control system open. The so-called open numerical control system is the development of the numerical control system can be on unified operation platform, face the lathe producer and end user, through changing, increasing or cutting out the structure target(numerical control function), form the serration, and can use users specially conveniently and the technical know-how is integrated in the control system, realize the open numerical control system of different variety , different grade fast, form leading brand products with distinct distinction. System structure norm of the open numerical control system at present, communication norm , disposing norm , operation platform , numerical control systematic function storehouse and numerical control systematic function software development ,etc. are the core of present research.The networked numerical control equipment is a new light spot of the fair of the internationally famous lathe in the past two years. Meeting production line , manufacture system , demand for the information integration of manufacturing company networkedly greatly of numerical control equipment, realize new manufacture mode such as quick make , fictitious enterprise , basic Entrance that the whole world make too. Some domestic and international famous numerical control lathes and systematic manufacturing companies of numerical control have all introduced relevant new concepts and protons of a machine in the past two years, if in EMO2001 exhibition, " Cyber Production Center " that the company exhibits of mountain rugged campstool gram in Japan (Mazak) (intellectual central production control unit, abbreviated as CPC); The lathe company of Japanese big Wei (Okuma ) exhibits " IT plaza " (the information technology square , is abbreviated as IT square ); Open Manufacturing Environment that the company exhibits of German Siemens (Siemens ) (open the manufacturing environment, abbreviated as OME),etc., have reflected numerical control machine tooling to the development trend of networked direction.5.4 Pay attention to the new technical standard, normal setting-up5.4.1 Design the norm of developing about the numerical control systemAs noted previously, there are better common ability, flexibility, adaptability, expanding in the open numerical control system, such countries as U.S.A. ,European Community and Japan ,etc. implement the strategic development plan one after another , carry on the research and formulation of the systematic norm (OMAC , OSACA , OSEC ) of numerical control of the open system structure, 3 biggest economies in the world have carried on the formulation that nearly the same science planned and standardized in a short time, have indicated a new arrival of period of change of numerical control technology. Our country started the research and formulation of standardizing the frame of ONC numerical control system of China too in 2000.5.4.2 About the numerical control standardThe numerical control standard is a kind of trend of information-based development of manufacturing industry. Information exchange among 50 years after numerical control technology was born was all because of ISO6983 standard, namely adopt G, M code describes how processes,。
机械专业外文翻译---带式输送机及其牵引系统
外文翻译英文原文Belt Conveying Systems Development of driving systemAmong the methods of material conveying employed，belt conveyors play a very important part in the reliable carrying of material over long distances at competitivecost．Conveyor systems have become larger and more complex and drive systems have also been going through a process of evolution and will continue to do so．Nowadays，bigger belts require more power and have brought the need for larger individual drives as well as multiple drives such as 3 drives of 750 kW for one belt(this is the case for theconveyor drives in Chengzhuang Mine)．The ability to control drive acceleration torque is critical to belt conveyors’ performance．An efficient drive system should be able toprovide smooth，soft starts while maintaining belt tensions within the specified safelimits．For load sharing on multiple drives．torque and speed control are also important considerations in the drive system’s design. Due to the advances in conveyor drive control technology，at present many more reliable．Cost-effective and performance-drivenconveyor drive systems covering a wide range of power are available for customers’choices[1].1 Analysis on conveyor drive technologies1．1 Direct drivesFull-voltage starters．With a full-voltage starter design，the conveyor head shaft is direct-coupled to the motor through the gear drive．Direct full-voltage starters are adequate for relativelylow-power, simple-profile conveyors．With direct fu11-voltage starters．no control is provided for various conveyor loads and．depending on the ratio between fu11- and no-1oad power requirements，empty starting times can be three or four times faster than full load．The maintenance-free starting system is simple，low-cost and very reliable．However, they cannot control starting torque and maximum stall torque；therefore．they are limited to the low-power, simple-profile conveyor belt drives．Reduced-voltage starters．As conveyor power requirements increase，controlling the appliedmotor torque during the acceleration period becomes increasingly important．Because motor torque 1s a function of voltage，motor voltage must be controlled．This can be achieved through reduced-voltage starters by employing a silicon controlled rectifier(SCR)．A common starting method with SCR reduced-voltage starters is to apply low voltage initially to take up conveyor belt slack．and then to apply a timed linear ramp up to full voltage and belt speed．However, this starting method will not produce constant conveyor belt acceleration．When acceleration is complete．the SCRs, which control the applied voltage to the electric motor．are locked in full conduction, providing fu11-line voltage to the motor．Motors with higher torque and pull—up torque，can provide better starting torque when combined with the SCR starters, which are available in sizes up to 750 KW．Wound rotor induction motors．Wound rotor induction motors are connected directly to the drive system reducer and are a modified configuration of a standard AC induction motor．By insert ing resistance in series with the motor’s rotor windings．the modified motor control system controls motor torque．For conveyor starting，resistance is placed in series with the rotor for low initial torque．As the conveyor accelerates，the resistance is reduced slowly to maintain a constant acceleration torque．On multiple-drive systems．an external slip resistor may be left in series with the rotor windings to aid in load sharing．The motor systems have a relatively simple design．However, the control systems for these can be highly complex，because they are based on computer control of the resistance switching．Today，the majority of control systems are custom designed to meet a conveyor system’s particular specifications．Wound rotor motors are appropriate for systems requiring more than 400 kW ．DC motor．DC motors．available from a fraction of thousands of kW ，are designed to deliver constant torque below base speed and constant kW above base speed to the maximum allowable revolutions per minute(r/min)．with the majority of conveyor drives, a DC shunt wound motor is used．Wherein the motor’s rotating armature is connected externally．The most common technology for controlling DC drives is a SCR device．which allows for continual variable-speed operation．The DC drive system is mechanically simple, but can include complex custom-designed electronics to monitor and control the complete system．This system option is expensive in comparison to other soft-start systems．but it is a reliable, cost-effective drive in applications in which torque,1oad sharing and variable speed are primary considerations．DC motors generally are used with higher-power conveyors，including complex profile conveyorswith multiple-drive systems，booster tripper systems needing belt tension control and conveyors requiring a wide variable-speed range．1．2 Hydrokinetic couplingHydrokinetic couplings，commonly referred to as fluid couplings．are composed of three basic elements; the driven impeller, which acts as a centrifugal pump；the driving hydraulic turbine known as the runner and a casing that encloses the two power components．Hydraulic fluid is pumped from the driven impeller to the driving runner, producing torque at the driven shaft．Because circulating hydraulic fluid produces the torque and speed，no mechanical connection is required between the driving and driven shafts．The power produced by this coupling is based on the circulated fluid’s amount and density and the torque in proportion to input speed．Because the pumping action within the fluid coupling depends on centrifugal forces．the output speed is less than the input speed．Referred to as slip．this normally is between l% and 3%．Basic hydrokinetic couplings are available in configurations from fractional to several thousand kW ．Fixed-fill fluid couplings．Fixed-fill fluid couplings are the most commonly used soft-start devices for conveyors with simpler belt profiles and limited convex/concave sections．They are relatively simple,1ow-cost,reliable,maintenance free devices that provide excellent soft starting results to the majority of belt conveyors in use today．Variable-fill drain couplings．Drainable-fluid couplings work on the same principle as fixed-fill couplings．The coupling’s impellers are mounted on the AC motor and the runners on the driven reducer high-speed shaft．Housing mounted to the drive base encloses the working circuit．The coupling’s rotating casing contains bleed-off orifices that continually allow fluid to exit the working circuit into a separate hydraulic reservoir．Oil from the reservoir is pumped through a heat exchanger to a solenoid-operated hydraulic valve that controls the filling of the fluid coupling．To control the starting torque of a single-drive conveyor system，the AC motor current must be monitored to provide feedback to the solenoid control valve．Variable fill drain couplings are used in medium to high-kW conveyor systems and are available in sizes up to thousands of kW ．The drives can be mechanically complex and depending on the control parameters．the system can be electronically intricate．The drive system cost is medium to high, depending upon size specified．Hydrokinetic scoop control drive．The scoop control fluid coupling consists of the threestandard fluid coupling components：a driven impeller, a driving runner and a casing that encloses the working circuit．The casing is fitted with fixed orifices that bleed a predetermined amount of fluid into a reservoir．When the scoop tube is fully extended into the reservoir, the coupling is l00 percent filled．The scoop tube, extending outside the fluid coupling，is positioned using an electric actuator to engage the tube from the fully retracted to the fully engaged position．This control provides reasonably smooth acceleration rates．to but the computer-based control system is very complex．Scoop control couplings are applied on conveyors requiring single or multiple drives from l50 kW to 750 kW.1．3 Variable-frequency control(VFC)Variable frequency control is also one of the direct drive methods．The emphasizing discussion about it here is because that it has so unique characteristic and so good performance compared with other driving methods for belt conveyor．VFC devices Provide variable frequency and voltage to the induction motor, resulting in an excellent starting torque and acceleration rate for belt conveyor drives．VFC drives．available from fractional to several thousand(kW ), are electronic controllers that rectify AC line power to DC and，through an inverter, convert DC back to AC with frequency and voltage contro1．VFC drives adopt vector control or direct torque control(DTC)technology，and can adopt different operating speeds according to different loads．VFC drives can make starting or stalling according to any givenS-curves．realizing the automatic track for starting or stalling curves．VFC drives provide excellent speed and torque control for starting conveyor belts．and can also be designed to provide load sharing for multiple drives．easily VFC controllers are frequently installed on lower-powered conveyor drives，but when used at the range of medium-high voltage in the past．the structure of VFC controllers becomes very complicated due to the limitation of voltage rating of power semiconductor devices，the combination of medium-high voltage drives and variable speed is often solved with low-voltage inverters using step-up transformer at the output，or with multiple low-voltage inverters connected in series．Three-level voltage-fed PWM converter systems are recently showing increasing popularity for multi-megawatt industrial drive applications because of easy voltage sharing between the series devices and improved harmonic quality at the output compared to two-level converter systems With simple series connection of devices．This kind of VFC system with three 750 kW /2．3kV inverters has been successfully installed in ChengZhuang Mine for one 2．7-km long belt conveyor driving system in followingthe principle of three-level inverter will be discussed in detail．2 Neutral point clamped(NPC)three-level inverter using IGBTsThree-level voltage-fed inverters have recently become more and more popular for higher power drive applications because of their easy voltage sharing features．1ower dv/dt per switching for each of the devices，and superior harmonic quality at the output．The availability of HV-IGBTs has led to the design of a new range of medium-high voltage inverter usingthree-level NPC topology．This kind of inverter can realize a whole range with a voltage rating from 2．3 kV to 4．1 6 kV Series connection of HV-IGBT modules is used in the 3．3 kV and 4．1 6 kV devices．The 2．3 kV inverters need only one HV-IGBT per switch[2,3].2．1 Power sectionTo meet the demands for medium voltage applications．a three-level neutral point clamped inverter realizes the power section．In comparison to a two-level inverter．the NPC inverter offers the benefit that three voltage levels can be supplied to the output terminals，so for the same output current quality，only 1/4 of the switching frequency is necessary．Moreover the voltage ratings of the switches in NPC inverter topology will be reduced to 1/2．and the additional transient voltage stress on the motor can also be reduced to 1/2 compared to that of a two-level inverter．The switching states of a three-level inverter are summarized in Table 1．U．V and W denote each of the three phases respectively；P N and O are the dc bus points．The phase U，for example，is in state P(positive bus voltage)when the switches S1u and S2u are closed，whereas it is in state N (negative bus voltage) when the switches S3u and S4u are closed．At neutral point clamping，the phase is in O state when either S2u or S3u conducts depending on positive or negative phase current polarity，respectively．For neutral point voltage balancing，the average current injected at O should be zero．2．2 Line side converterFor standard applications．a l2-pulse diode rectifier feeds the divided DC-link capacitor．This topology introduces low harmonics on the line side．For even higher requirements a 24-pulse diode rectifier can be used as an input converter．For more advanced applications where regeneration capability is necessary, an active front．end converter can replace the diode rectifier, using the same structure as the inverter．2．3 Inverter controlMotor Contro1．Motor control of induction machines is realized by using a rotor flux．oriented vector controller．Fig．2 shows the block diagram of indirect vector controlled drive that incorporates both constant torque and high speed field-weakening regions where the PW M modulator was used．Inthis figure，the command flux is generated as function of speed．The feedback speed isadded with the feed forward slip command signal . the resulting frequency signal isintegrated and then the unit vector signals(cos and sin)are generated．The vector rotatorgenerates the voltage and angle commands for the PW M as shown．PWM Modulator．The demanded voltage vector is generated using an elaborate PWM modulator．The modulator extends the concepts of space-vector modulation to the three-level inverter．The operation can be explained by starting from a regularly sampled sine-triangle comparison from two-level inverter．Instead of using one set of reference waveforms and one triangle defining the switching frequency，the three-level modulator uses two sets of reference waveforms U r1 and U r2 and just one triangle．Thus, each switching transition is used in an optimal way so that several objectives are reached at the same time．Very low harmonics are generated．The switching frequency is low and thus switching losses are minimized．As in a two-level inverter, a zero-sequence component can be added to each set of reference waveform s in order to maximize the fundamental voltage component．As an additional degree of freedom，the position of the reference waveform s within the triangle can be changed．This can be used for current balance in the two halves of the DC-1ink．3 Testing resultsAfter Successful installation of three 750 kW /2．3 kV three-level inverters for one 2．7 km long belt conveyor driving system in Chengzhuang Mine．The performance of the whole VFC system was tested．Fig．3 is taken from the test，which shows the excellent characteristic of the belt conveyor driving system with VFC controller．Fig．3 includes four curves．The curve 1 shows the belt tension．From the curve it can be find that the fluctuation range of the belt tension is very smal1．Curve 2 and curve 3 indicate current and torque separately．Curve 4 shows the velocity of the controlled belt．The belt velocity have the“s”shape characteristic．A1l the results of the test show a very satisfied characteristic for belt driving system．4 ConclusionsAdvances in conveyor drive control technology in recent years have resulted in many more reliable．Cost-effective and performance-driven conveyor drive system choices for users．Among these choices，the Variable frequency control (VFC) method shows promising use in the future for long distance belt conveyor drives due to its excellent performances．The NPC three-level inverter using high voltage IGBTs make the Variable frequency control in medium voltage applications become much more simple because the inverter itself can provide the medium voltage needed at the motor terminals，thus eliminating the step-up transformer in most applications in the past．The testing results taken from the VFC control system with NPC three．1evel inverters used in a 2．7 km long belt conveyor drives in Chengzhuang Mine indicates that the performance of NPC three-level inverter using HV-IGBTs together with the control strategy of rotor field-oriented vector control for induction motor drive is excellent for belt conveyor driving system．中文译文：带式输送机及其牵引系统在运送大量的物料时，带式输送机在长距离的运输中起到了非常重要的竞争作用。
机械制造专业外文翻译--成组技术
外文原文：Group TechnologyGroup technology (GT) is a very important methodology in today’s manufacturing significant. The reason for this is that group technology, when utilized to its fullest extent, can affect most areas of manufacturing, including design, process planning, scheduling, routing, factory layout, procurement, quality assurance, machine tool utilization, tool design, producibility engineering, and assembly.1 IntroductionGroup technology is a simple concept that is used widely in various forms. For a variety of reasons, it is logical to collect and associate things based on features that they have in common. This approach is familiar to everyone for plants, animals, and chemicals. Such organizational structures have also been used for hardware and other obviously similar products within the manufacturing world. Group technology represents structured categorization of particular value to the manufacturing community. It is already widely used; perhaps 50% of manufacturing companies use some form of GT.Bath or lot production suffers from many inefficiencies due to part variety and the general-purpose nature (flexibility requirements) of machine tools in use on the shop floor. In fact, a Cincinnati Milacron study showed that 95% of the time a part spends on the shop floor is idle time, the other 5% is divided between setup and teardown of the machine tool. The future breakdown of the 5% of on-machine time was developed by Dunlap. Based on this estimate, only 24% of the 5% is time which actually involves cutting; i.e., parts are being machined during only 1.2% of the total time spent in manufacturing. Group technology makes possible the application of several methods of analysis which assist in making batch production more efficient by reducing part variety via part families and improving throughout and work-in-process inventory. It is for this reason that group technology is becoming a key concept in manufacturing.2 DefinitionManufacturing philosophy to some, fundamental building block for more efficient production to most, group technology is a simple concept which utilizes/exploits similarities for more efficient production in bath manufacturing. Group technology usually classifies parts in the form of a code which is assigned to each part based on its shape or production processing characteristics. In use, coding parts assists in the control of planning and processing. This added control, which exploits similarities, leads to economies in the overall manufacturing process. The actual operator on the shop floor may never know this code, but designers, engineers, and planners find it an invaluable tool, allowing them to do more productive and useful analysis.3 General BenefitsIn practice, group technology is really nothing more than an information/indexing system. However, because of its focus on part design andprocessing similarities, analysis is possible which creates manufacturing economies of scale, encourages standardization, and eliminates duplication in design and process planning.Mass production enjoys the benefits of what are called economies of scale. Economies of scale achieved by processing a large number of parts over the same workstations or equipment. This result in less labor per part, more efficient machine utilization, and a faster turnover of inventory. Batch production in the past has not enjoyed economies of scale because of the need to remain flexible for changing part types and products. However, by grouping parts into families based on their similarities, much of the manufacturing processing of these parts can be done on entire families. This increases the number of parts processed with the same equipment conditions, thereby permitting some of the economies of scale of mass production.Standardization is achieved in both design and part process planning. Essentially, group technology creates an efficient design retrieval system since parts have been code based on shape. Similar design are located quickly and aspects such as part tolerances and producibility can be better understood, more easily applied, and kept more consistent from design to design. When standardized process planes are developed and include in the group technology code, new parts and repeat orders can follow similar processing routes through the shop floor, simplifying scheduling and flow through the shop.Group technology eliminates duplication. In both design and process planning, there is much les “reinventing of the wheel”since there is sufficient retrieval of standard designs and process plans.4 Application of GT in Process PlanningAlthough many areas of business operation can benefit from GT, manufacturing, the original application area, continues to be the place where GT is most widely practiced. Two important tasks in manufacturing planning and manufacturing engineering are scheduling and process planning. Job scheduling sets the order in which parts should be processed and can determine expected completion times for operation and orders. Process planning, on the other hand, decides the sequence of machines to which a part should be routed when it is manufactured and the operations that should be performed at each machine. Process planning also encompasses tool, jig, and fixture selection as well as documentation of the time standards (run and setup time) associated with each operation. Process planning can directly affect scheduling efficiency and, thus, many of the performance measures normally associated with manufacturing planning and control.Some of the largest productivity gains have been reported in the creation of process plans that determine how a part should be produced. With computer-aided process planning (CAPP) and GT it is possible to standardize such plans, reduce the number of new ones, and store, retrieve, edit, and print them out very efficiently.Process planning normally is not a formal procedure. Each time a new part is designed, a process planner will look at the drawing and decide which machine tools should process the parts, which operations should be performed, and in what sequence There are two reasons why companies often generate excess process plans. First,most companies have several planners, and each may come up with a different process plan for the very same part, Second, process; planning is developed with the existing configuration of machine tools in mind. Over time, the addition of new equipment will change the suitability of existing plans. Rarely are alterations to old process plans made. One company reportedly had 477 process plans developed for 523 different gears. A close look revealed that more than 400 of the plans could be eliminated. Process planning using CAPP can avoid these problems.Process planning with CAPP takes two different forms;With variant-based planning, one standardized plan (and possibly one or more alternate plans) is created and stored for each part family. When the planner enters the GT code for a part, the computer will retrieve the best process plan. If none exists, the computer will search for routings and operations for similar parts. The planner can edit the scheme on the CRT screen before printout.With generative planning, which can but does not necessarily rely on coded and classified parts, the computer forms the process plan through a series of questions the computer poses on the screen. The end product is also a standardized process plan, which is the best plan for a particular part.The variant-based approach relied on established plans entered into the computer memory, while the generative technique creates the process plans interactively, relying on the same logic and knowledge that a planner has. Generative process planning is much more complex than variant-based planning; in fact, it approaches the art of artificial intelligence. It is also much more flexible; by simply changing the planning logic, for instance, engineers can consider the acquisition of a new machine tool. With the variant-based method, the engineers must look over and possibly correct all plans that the new tool might affect.CAPP permits creation and documentation of process plans in a fraction of the time it would take a planner to do the work manually and vastly reduces the number of errors and the number of new plans that must be stored. When you consider that plans normally are handwritten and that process planners spend as much as 30% of their time preparing them, CAPP’S contribution of standardized formats for plans and more readable documents is important. CAPP, in effect, functions as advanced text editor. Furthermore, it can be linked with an automated standard data system that will calculate and record the run times and the setup times for each operation.CAPP can lead to lower unit costs through production of parts in an optimal way. That is, cost savings come not only via more efficient process planning but also through reduced labor, material, tooling, and inventory costs.GT can help in the creation of programs that operate numerically (NC) machinery, n area related to process planning. For example, after the engineers at Otis Engineering had formed part families and cells, the time to produce a new NC tape dropped from between 4 and 8 hours to 30 minutes. The company thereby improved the potential for use of NC equipment on batches with small manufacturing quantities.中文译文：成组技术在当今的制造环境下，尤其是对批量生产来说，成组技术（GT）是一个很重要的生产方式而且它正变得越来越重要。
机械工程及其自动化 专业外文资料翻译--流体传动
毕业设计(论文)外文资料翻译学院(系)：机械工程学院专业：机械工程及其自动化姓名：学号：外文出处：Transmission of Fluid附件： 1.外文资料翻译译文；2.外文原文。
注：请将该封面与附件装订成册。
附件1：外文资料翻译译文流体传动流体传动包括气体(压)传动和液体传动，液体传动分为液压传动、液力传动和液粘传动。
液压传动基于帕卡定律，以液体的压能来传递动力；液力传动基于欧拉方程，以液体动量短的变化来传递动力；液粘传动基于牛顿内摩擦定律，以液体的粘性来传递动力。
液力传动的基本元件是液力偶合器和液力变矩器。
液力偶合器的基本构件是具有若干径向平面叶片的、构成工作腔的泵轮和涡轮。
液力传动油在工作腔里高速循环流动传递动力，油液随从泵轮做牵连运动的同时因受离心力作用而做离心运动，从泵轮(及输入轴)吸收机械能并转化为动量矩(mVR)增量，高速液流从泵轮冲入涡轮做向心流动释放动量矩，推动涡轮(及输出轴)旋转，带动工作机(及负载)做功。
液力变矩器的基本构件是泵轮、涡轮和导轮，它们均是具有空间(弯曲)叶片的工作轮，按相关顺序排列构成工作腔。
液力传动油在工作腔中被泵轮涡轮搅动，使液流获得动量矩增量，经过导轮调转液流方向后冲入涡轮，释放动量矩(动能)推动涡轮带动工作机旋转做功。
我国液力元件近年发展较快，2003年液力偶合器的全国年产量约7万台。
广泛应用于带式输送机、刮板输送机、球磨机、风机、压缩机、水泵和油泵等设备的传动中，提高传动品质并节约能源。
当前我国液力偶合器的最高输出转速为6500r/min，最小功率为0.3kW，最大功率为7100kW。
液力偶合器的发展趋势是高转速、大功率。
国际上液力偶合器产品以德国福依特公司最为著名，据资料称已有转速达20000r/min、功率达55000kW的产品，可见我国与之尚有相当大的差距。
当然，功率大的液力元件对液力传动油的要求较高。
液力变矩器主要用于工程机械、石油机械和内燃机车。
机械设计制造及其自动化毕业论文中英文资料外文翻译
机械设计创造及其自动化毕业论文外文文献翻译INTEGRATION OF MACHINERY译文题目专业机械设计创造及其自动化外文资料翻译INTEGRATION OF MACHINERY（From ELECTRICAL AND MACHINERY INDUSTRY）ABSTRACTMachinery was the modern science and technology development inevitable result, this article has summarized the integration of machinery technology basic outline and the development background .Summarized the domestic and foreign integration of machinery technology present situation, has analyzed the integration of machinery technology trend of development.Key word： integration of machinery ，technology， present situation ，product t，echnique of manufacture ，trend of development0. Introduction modern science and technology unceasing development, impelled different discipline intersecting enormously with the seepage, has caused the project domain technological revolution and the transformation .In mechanical engineering domain, because the microelectronic technology and the computer technology rapid development and forms to the mechanical industry seepage the integration of machinery, caused the mechanical industry the technical structure, the product organization, the function and the constitution, the production method and the management systemof by machinery for the characteristic integration ofdevelopment phase.1. Integration of machinery outline integration of machinery is refers in the organization new owner function, the power function, in the information processing function and the control function introduces the electronic technology, unifies the system the mechanism and the computerization design and the software which constitutes always to call. The integration of machinery development also has become one to have until now own system new discipline, not only develops along with the science and technology, but also entrusts with the new content .But its basic characteristic may summarize is: The integration of machinery is embarks from the system viewpoint, synthesis community technologies and so on utilization mechanical technology, microelectronic technology, automatic control technology, computer technology, information technology, sensing observation and control technology, electric power electronic technology, connection technology, information conversion technology as well as software programming technology, according to the system function goal and the optimized organization goal, reasonable disposition and the layout various functions unit, in multi-purpose, high grade, redundant reliable, in the low energy consumption significance realize the specific function value, and causes the overall system optimization the systems engineering technology .From this produces functional system, then becomes an integration of machinery systematic or the integration of machinery product. Therefore, of coveringtechnology is based on the above community technology organic fusion one kind of comprehensive technology, but is not mechanical technical, the microelectronic technology as well as other new technical simple combination, pieces together .This is the integration of machinery and the machinery adds the machinery electrification which the electricity forms in the concept basic difference .The mechanical engineering technology has the merely technical to develop the machinery electrification, still was the traditional machinery, its main function still was replaces with the enlargement physical strength .But after develops the integration of machinery, micro electron installment besides may substitute for certain mechanical parts the original function, but also can entrust with many new functions,like the automatic detection, the automatic reduction information, demonstrate the record, the automatic control and the control automatic diagnosis and the protection automatically and so on .Not only namely the integration of machinery product is human's hand and body extending, human's sense organ and the brains look, has the intellectualized characteristic is the integration of machinery and the machinery electrification distinguishes in the function essence.2. Integration of machinery development condition integration of machinery development may divide into 3 stages roughly.20th century 60's before for the first stage, this stage is called the initial stage .In this time, the people determination not on own initiative uses the electronic technology the preliminary achievement to consummate the mechanical product the performance .Specially in Second World War period, the war has stimulated the mechanical product and the electronic technology union, these mechanical and electrical union military technology, postwar transfers civilly, to postwar economical restoration positive function .Developed and the development at that time generally speaking also is at the spontaneouscondition .Because at that time the electronic technology development not yet achieved certain level, mechanical technical and electronic technology union also not impossible widespread and thorough development, already developed the product was also unable to promote massively. The 20th century 70~80 ages for the second stage, may be called the vigorous development stage .This time, the computer technology, the control technology, the communication development, has laid the technology base for the integration of machinery development . Large-scale, ultra large scale integrated circuit and microcomputer swift and violent development, has provided the full material base for the integration of machinery development .This time characteristic is :①A mechatronics word first generally is accepted in Japan, probably obtains the quite widespread acknowledgment to 1980s last stages in the worldwide scale ;②The integration of machinery technology and the product obtained the enormous development ;③The various countries start to the integration of machinery technology and the product give the very big attention and the support. 1990s later periods, started the integration of machinery technology the new stagewhich makes great strides forward to the intellectualized direction, the integration of machinery enters the thorough development time .At the same time, optics, the communication and so on entered the integration of machinery, processes the technology also zhan to appear tiny in the integration of machinery the foot, appeared the light integration of machinery and the micro integration of machinery and so on the new branch; On the other hand to the integration of machinery system modeling design, the analysis and the integrated method, the integration of machinery discipline system and the trend of development has all conducted the thorough research .At the same time, because the hugeprogress which domains and so on artificial intelligence technology, neural network technology and optical fiber technology obtain, opened the development vast world for the integration of machinery technology .These research, will urge the integration of machinery further to establish the integrity the foundation and forms the integrity gradually the scientific system. Our country is only then starts from the beginning of 1980s in this aspect to study with the application .The State Councilsummary had considered fully on international the influence which and possibly brought from this about the integration of machinery technology developmenttrend .Many universities, colleges and institutes, the development facility and some large and middle scale enterprises have done the massive work to this technical development and the application, does not yield certain result, but and so on the advanced countries compared with Japan still has the suitable disparity.3. Integration of machinery trend of development integrations of machinery are the collection machinery, the electron, optics, the control, the computer, the information and so on the multi-disciplinary overlapping syntheses, its development and the progress rely on and promote the correlation technology development and the progress .Therefore, the integration of machinery main development direction is as follows:3.1 Intellectualized intellectualizations are 21st century integration of machinery technological development important development directions .Theartificial intelligence obtains day by day in the integration of machinery constructor's research takes, the robot and the numerical control engine bedis to the machine behavior description, is in the control theory foundation, the absorption artificial intelligence, the operations research, the computer science, the fuzzy mathematics, the psychology, the physiology and the chaos dynamics and so on the new thought, the new method, simulate the human intelligence, enable it to have abilities and so on judgment inference, logical thinking, independent decision-making, obtains the higher control goal in order to .Indeed, enable the integration of machinery product to have with the human identical intelligence, is not impossible, also is nonessential .But, the high performance, the high speed microprocessor enable the integration of machinery product to have preliminary intelligent or human's partial intelligences, then is completely possible and essential.In the modern manufacture process, the information has become the control manufacture industry the determining factor, moreover is the most active actuation factor .Enhances the manufacture system information-handling capacity to become the modern manufacture science development a key point .As a result of the manufacture system information organization and structure multi-level, makes the information the gain, the integration and the fusion presents draws up the character, information measure multi-dimensional, as well as information organization's multi-level .In the manufacture information structural model, manufacture information uniform restraint, dissemination processing and magnanimous data aspects and so on manufacture knowledge library management, all also wait for further break through.Each kind of artificial intelligence tool and the computation intelligence method promoted the manufacture intelligence development in the manufacture widespread application .A kind based on the biological evolution algorithm computation intelligent agent, in includes thescheduling problem in the combination optimization solution area of technology, receives the more and more universal attention, hopefully completes the combination optimization question when the manufacture the solution speed and the solution precision aspect breaks through the question scale in pairs the restriction .The manufacture intelligence also displays in: The intelligent dispatch, the intelligent design, the intelligent processing, the robot study, the intelligent control, the intelligent craft plan, the intelligent diagnosis and so on are various These question key breakthrough, may form the product innovation the basic research system. Between 2 modern mechanical engineering front science different science overlapping fusion will have the new science accumulation, the economical development and society's progress has had the new request and the expectation to the science and technology, thus will form the front science .The front science also has solved and between the solution scientific question border area .The front science has the obvious time domain, the domain and the dynamic characteristic .The project front science distinguished in the general basic science important characteristic is it has covered the key science and technology question which the project actual appeared.Manufacture system is a complex large-scale system, for satisfies the manufacture system agility, the fast response and fast reorganization ability, must profit from the information science, the life sciences and the social sciences and so on the multi-disciplinary research results, the exploration manufacture system new architecture, the manufacture pattern and the manufacture system effective operational mechanism .Makes the system optimization the organizational structure and the good movement condition is makes the system modeling , the simulation and the optimized essential target .Not only the manufacture system new architecture to makes the enterprise the agility and may reorganize ability to the demand response ability to have the vital significance, moreover to made the enterprise first floor production equipment the flexibility and may dynamic reorganization ability set a higher request .The biological manufacture view more and more many is introduced the manufacture system, satisfies the manufacture system new request.The study organizes and circulates method and technique of complicated system from the biological phenomenon, is a valid exit which will solve many hard nut to cracks that manufacturing industry face from now on currently .Imitating to living what manufacturing point is mimicry living creature organ of from the organization, from match more, from growth with from evolution etc. function structure and circulate mode of a kind of manufacturing system and manufacturing process.The manufacturing drives in the mechanism under, continuously by one's own perfect raise on organizing structure and circulating mode and thus to adapt the process of[with] ability for the environment .For from descend but the last product proceed together a design and make a craft rules the auto of the distance born, produce system of dynamic state reorganization and product and manufacturing the system tend automatically excellent provided theories foundation and carry out acondition .Imitate to living a manufacturing to belong to manufacturing science and life science of"the far good luck is miscellaneous to hand over", it will produce to the manufacturing industry for 21 centuries huge of influence .机电一体化摘要机电一体化是现代科学技术发展的必然结果,本文简述了机电一体化技术的基本概要和发展背景。
机械专业外文翻译---精密体积成形模具的设计制造及发展
Volume precision forming mold design andmanufacturing and developmentAuxiliary processing technologyIn the production process, improve die life is a complex comprehensive issues. All forging process, especially the net shape and approximate net form processing technologyMuch depends on the accuracy and quality, depending on the technology level of mould. Mould technology reflected in moulding design and manufacturing,And die life with the above two links in the outside, still and use the link. Improve die life is of great economic benefits, generally in the trial production mold tooling cost accounting for stage production cost of about 25%, and finalize the design production is only 10%.Die early failure forms, many for the punch and die of fracture bore edge collapse, flash in the bridge chap, cavity occurred crack at the bottom. Many factors influence the life of die a wide range and die design the life of die is based. Die design link is refers to the mould structure plan, set Forming design and determine the cavity of the steel, mould hardness etc. Mould manufacturing process is to point to die making technology, heat treatment standard and surface treatment technology, etc.In this paper, only from the mold design and die manufacturing two aspects to study and improve the life of die measures.1, the reasonable design precision volume forming a (fine forging)Die forgings should try to avoid with holes, narrow slot, Angle, shape should as far as possible is symmetrical, even if they can't do axisymmetric, also hope to achieve,Under symmetrical or left, right symmetry. To design mold pulling out rake, avoid stress concentration and die forging units, increasing the pressure overcome eccentric loading and mould wear not equal defect. For forging die cavity edge and bottom fillet radius R, design should ensure forgings cavity is easily filled with the premise of amplification.If the fillet radius is too small, easily cavity edge in high temperature and high pressure of collapse, the serious will form the reversed cone, influence die forgings the mold.Such as the bottom fillet radius R is too small and is not smooth transition, it's easy to crack and will continue to expand.When the mould design should make full use of CAD system for products function 2 d and 3 d design, to ensure that the products to the unity of the original information and accuracy,Avoid man-made errors, improve the mould design quality.Three-dimensional modelling product in forging process to reflect the product before comprehensive external shape,Timely find that the original design of the possible problems, at the same time, according to the product information, a computer design processing die-cavity roughing electrode, ready for the follow-up mold processing. The CAM technology can design according to the electrode accurately designated production mode. Adopt CNC milling machine (or processing center) processing electrode,Can ensure the machining precision of the electrode and reduce the time of the mould try, reduce scrap rate of the die and FanXiuLv, reduce the amount of fitter.For some complex shape, high accuracy of forgings,By the conventional die locksmith mould manufacturing methods guarantee certain size and shape using CAD/CAM technology in the complex forgings precise dimensions description,The determination of reasonable parting surface to ensure accuracy molmerged, from the mould manufacturing this link to ensure product precision.CAD/CAM/CAE technology can be finite element analysis, the size of the key parts of the design is reasonable can provide modification basis, Thus in for customers with high quality forgings, but also for the design of the customer provide the basis, strengthen the cooperation with the customers.Forming is the most important in the process of die forging work step, die forgings geometry is to rely on to ensure the forging die, die forging process to fully consider all sorts of factors,Especially in production possible or has exposed problems, in the mold design measures should be taken to reduce the follow-up process of processing difficulty. According to this principle in prevention to reduce die forgings craze and deformation, improving forgings qualified rate, can have pointed to take some countermeasures and measures. Such as forgings in certain parts of the machine and punching easily to affect the quality of products and deformation,But in the forging die design appropriate increase deformation parts of the machining allowance compensation, this is when the large deformation forging machine thin flange is more important.For some with stem and stem diameter relatively small forgings, in trimming and heat treatment process will produce regular geometric distortion,And with cold correction methods do not or difficult to straightening. As a factory TS60 crankshaft,According to the practical experience and statistical data center in advance will be in a certain range of reverse migration direction deformation must advance the deformation for.2, the reasonable design forging processAt present, the general enterprise without sound technology lab, lack of process test conditions, which requires process program must be correct and a success. Especially after step into the market economy, the responsible person of the enterprise technical personnel can only request forging success, not to fail, this will give process design personnel brought the big difficult for process engineering is of high level to, but even with rich practical experience in the process are also hard to avoid can feel awkward, once mistakes can cause bigger loss.For trimming to the existing tear part in design flash slots can be forging when the thinning weak parts to the height of the bridge flash, and to decrease the cut when cut thickness of flash here. Such as S195 connecting rod, materials for 45 steel, after cold forging machine, a big head ZiBu due to section shape a small, thin material, often appear in trimming a near the children and the muscle tear, and scrap rate is high. If instead of waste can be after forging machine improve trimming quality, but because trimming production by die forging beat of limit, the efficiency is low. And in forging die design thinning here when the height of the bridge flash, reduce the flash cutting force, can greatly reduce trimming tear.For cold extrusion technology, must be the greatest degree softening and reduce blank when the deformation friction force, strictly control thedeformation degree and each working procedure, deformation degree distribution.General low carbon steel, carbon steel and low carbon steel alloy softening annealing process for: heating to 760 ℃heat preservation 4 h, By 20 ℃/ h the cooling speed of cold to 680 ℃heat preservation 3 h, again with 20 ℃/ h of the cooling speed to 640 ℃after cooling furnace cooling to 350 ℃Blackburn.Hardness general can reach 125-155 HB.Less than 0.2% of the carbon content of carbon steel, steel the annealing can less than 120 HB hardness. The steel softening annealing then through roll light, acid, phosphate,Saponification besmear again after lard mix MoS-2 lubrication, may reduce the deformation load, effectively reduce the punch, molding cycle, joint body the fracture failure.The small deformation process of cold extrusion method can reduce the impact extrusion die under unit, not on the blank between production processes softening,Make die life prolonged. Some domestic manufacturers in the extrusion production of covet a will, reduce the extrusion process, although also can get samples (or product) make,But mould load is too big, prone to failure. This kind of practice is quick in cold extrusion technology once a boom and has failed to the development of the main technical reasons. The forging die CAE software, you can analyze the material flow, friction resistance and material filling overflow cavity,To help design personnel reasonably effective process design.3, reasonable structure of the die designThe mould structure design main consideration guidance accuracy reasonable, cutting clearance appropriate, rigid, consider using combined mold as far as possible.Formwork should have a good rigidity, do not only meet the required strength, template shoulds not be too thin, and where possible to add thick, even thickening 50%.Progressive die unfavorable use only 2 root guide pin orientation, should try to do four root guide pin orientation, this guide good performance. Because of increased stiffness, ensure the convex,Concave die gap even, make sure the punch and concave die won't happen touch cut phenomenon.Floating mode can avoid press mold to handle the bad influence of guidance accuracy. The punch should clamping reliable,When the check assembly to punch or concave die on the vertical axis of the level and up and down between the underside of the parallel degree. In the cold extrusion, punch and concave die of hardness to the right, to give full play to the fortitude to prolong life processing of potential.If W6Mo5Cr4V2 steel cold extrusion of the punch, when hardness 60 HRC frequency when normal use, life for 3000 ~ 3500.But if by that experience low hardness, plastic life must extend will greatly disappointed, when hardness for 57 ~ 58 HRC extrusion workpiece,The work of the punch with will be upsetting. A factory detection 1 a punch die extrusion after work with size found, upsetting a large increase from 0.01 to 0.04 mm.For hot press concave die cannot apply mechanically cold extrusion touch experience, when the three Cr2W8V steel hot press concave die from the hardness value > 40 HRC to 37 to 38 HRC,Service life from 1000 ~ 2000 times increased to 6000 ~ 8000 times. According to experience, different forging equipment for the hardness of forging die forging requirements are different, and even in the same kind of forging equipment of die forging, forging different products to mold hardness requirement is not the same. In forging flash resection, punchbottom should as far as possible with the hollows of forgings coincide with the surface. Such as cutters die forging a keen flash,Cut flash at the bottom of the punch hollow to and cutters arc of the handle fit, or in the cut in the process of flash, flash to cut the punch forgings to one side to flip, make the punch and concave die damage. Usually, the cutting clearance amplifier can extend life cut flash mode.4, reasonable selecting mould materialAccording to the working conditions and production mold batch of material itself and strong performance to selecting mould material, should as far as possible choose quality good steel.According to the information of the mould are being manufactured for high, but the material cost is only the price of general mold by 6% ~ 20%. To die material to a test, module should comply with the supply agreement, the chemical composition of the module to comply with the relevant provisions of the international. Only in the case that module qualified to forging. Large module (100 kg above) by electric steel slag re-melting H13 make sure internal quality,To avoid possible ingredients segregation, impurities such as internal defects exceed bid. To make use of the ultrasonic testing of nondestructive testing technology such as check to ensure that eachforgings internal quality is good, avoid possible metallurgy defects, will eliminate waste as soon as possible.5 and reasonable establishing the steel forging normsAccording to the carbide segregation to the influence of the die life, must limit the inhomogeneity of carbide degree of precision mould and load the slender punch,Must choose good toughness of high strength steel mold, carbide not uniformity should be controlled for not more than 3 grade. Cr12 steel carbide not uniformity level 3 than level 5 durability improve 1 times above. Roll silk die of carbide not uniformity for 5 ~ 6 grade most roll silk 2000 pieces, and not the homogeneous degree to improve carbide at level 1 ~ 2 can roll silk 550000 pieces. If carbide segregation serious, may cause overheat, burning, craze, collapse collapse, tensile blade, and early failure. Ribbon, mesh, large particles and large firing the carbon that is made of mould performance anisotropic, horizontal low intensity, and plastic also poor.According to the micro hardness measurement results, carbide normal distribution place for 740 ~ 760 HV, carbide concentration point is 920 ~ 940 HV,Carbide in 610 ~ 670 rare for HV, rare place in carbide to excessive tempering, hardness and strength is reduced, carbide FuJiOu often lack for tempering,Brittleness is big, and lead to mould upsetting or break.Through the forging can effectively improve the tool steel carbide segregation, generally after forging can reduce carbide segregation level 2, for a maximum of 3 grade. Had better use axial,Radial repeated heading pull (cross heading pull law), it is upsetting the raw materials in the section after two perpendicular direction heading out again and again, and finally to along the axial or horizontal forging into, repeat this process is called double cross heading pull out, repeat many times for many times that the dui pull out. For 50 mm diameter less than or equal to the high alloy steel, the carbide not uniformity in general than level 4, can meet the general mold use requirement.6, rational selection of heat treatment processHeat treatment is not to die early failure of the important reasons, according to a factory statistics, its accounts for about 35% of the mould early failure factors.Heat treatment including forging die after the annealing, rough machining of high temperature tempering or low temperature after the tempering, finish machining the quenching and tempering after, edm, line cuttinglater to stress low temperature firing back. Only cold heat processing is very good and cooperate with each other, to ensure good die life. The mold cavity and thin wall when the need to normal quenching temperature the ceiling, so that residual austenitic rises, make the mold from swell.Due to rapid heating heating time is short, to reduce the decarburization oxidation, small grains of carbon steel large-scale die quenching little deformation. For high speed steel paper with low quenching, high back to technology is more good, quenching temperature is low, tempering the higher temperature, can greatly improve the toughness, although rigidity decrease, but to improve for broken or fatigue damage of die life is very effective. Usually Cr12MoV harden steel heating temperature of 1000 ℃, the oil cold, then 220 ℃tempering. As in the heat treatment to advance a time before heat treatment, heat to 1100 ℃is the heat preservation, oil cold, 700 ℃high temperature tempering, then die life can be greatly improved. We in the early 70 s for 3 Cr2W8V steel and high quenching, high heat treatment cutters to process the hot forming die have been introduced and the good results, improve life more than twice as many. Low temperature of carbon nitrogen infiltration process, surface hardness of up to 1200 HV, also can greatly improve the die life.Low temperature electrolytic permeability can reduce sulfur metal deformation friction, improve the viscous resistance to bite. 6W6Mo5Cr4V steel making use of the punch cold extrusion,The low temperature of carbon nitrogen permeability, service life by an average of 1 times above, then the low temperature electrolytic permeability sulfur treatment can further improve life 50%.Die after quenching have a lot of residual stress, it often cause mould deformation even craze. In order to reduce residual stress,Mould should be hot after quenching follows, tempering should fully, tempering don't fully easy generation before grinding crack. For carbon steel, 200 ℃tempering 1 h,Residual stress can eliminate about 50%, tempering 2 h residual stress can eliminate about 75% ~ 80%, and if 500 ~ 600 ℃tempering 1 h, the residual stress can eliminate up to 90%. A factory CrWMn steel punch hardened tempering 1 h, use soon fracture, and when the tempering 2.5 h, use of fracture is not found.It shows that the tempering don't even, although the surface hardness meet the requirements, but work internal organization not even, eliminate the residual stress is not full, the mould easy early rupture failure.After tempering general is empty cold, in the tempering cooling process, the material internal may appear new tensile stress, should slow cold to 100 ~ 120 ℃released later,Or in high temperature after tempering plus a low temperature firing back. Surface coating layer of hardening technology PVD, CVD get great progress in recent years, some of the vacuum in PVD steamed plating, vacuum sputtering and ion plating, including ion plating has strong adhesion, pouring plating of sedimentary speed, pollution-free, etc. Ion plating technology in mould coating surface can be TiC, TiN, can prolong the service life of a few times to dozens of times. Ion plating is vacuum gas discharge steam film and the combination of a deposition.Hollow cathode discharge method (HCD method) is to use of vacuum pump and the vacuum, then to the gas pump into the reaction, and keep in the vacuum 10-5 ~ 10-2 Pa range,Use of low voltage large current HCD electron gun evaporate metal or compounds ionization, and work together to surface in a layer of protection membrane. In order to improve the efficiency of plating apply, General on the work piece on load voltage.The forging die surface treatment technology of domestic application not too much, this field is the necessary development. Overall the cavity of carburizing and seepage nitrogen, carbon and nitrogen boriding and ofpermeability and the mould cavity local spraying, brush plating and surface hardening support surfacing are promising, break through the field will make our country modeling technology is greatly improved. After the failure of the mould filling welding technology, the domestic early 90 s have the factory for research and application, such as forging plant in qinghai, weld repairs can improve the service life of the forging die after 1 times.7, reasonably determine the mechanical processing manufacturing process and the machining accuracyWith advanced equipment and technology to ensure that every vice mould has high precision and interchangeability in order to ensure that the forging die have high accuracy of the request and repeat precision. Manufacturing process to solve first for the processing of the machining deformation and residual stress can not be too big. Rough machining when had better not make the surface roughness Ra > 3.2 u m,Special attention should be in the mold working part corner to the smooth transition, reduce the heat generated by the heat stress.The cavity surface processing left at knife scar, grinding mark are stress concentration, the position is also early cracks and fatigue crack source, so in forging die when processing cutting tool must be good. Plane tools must be good at both ends often round R, circular arc cutting tools for Rgauge measurement, will never allow appear cusp. Walk in finishing the sword to small amount, not be allowed knife scar. For complex cavity must keep grinding surplus, even after processing no knife scar, also want to again by grinding wheel with pneumatic fitter (or in other methods) fine polishing, but be aware that prevent grind the local overheating, whenBurns surface and reduce the surface hardness.Mold machining surface hardening layer, thick 10 μ m or so, har dening layer is crisp and to have residual stress, direct use often cause early craze, such hardening layer in the 180 ℃or so low temperature can eliminate the tempering residual stress.This will cause if grinding heat invisible to the naked eye and grinding direction perpendicular tiny crack in stress function, crack will expand. To CrWMn steel cold extrusion die adopt concave dry grinding, grinding depth of 0.04 ~ 0.05 mm, use of cracking 100%; Adopt wet grinding, grinding depth 0.005 ~ 0.01 mm, the use of the good performance. Eliminate grinding stress can also will die in 260 ~ 315 ℃of salt bath at 1.5 min, and then in 30 ℃oil cooling, so can reduce 1 HRC hardness, residual stress reduced by 40% ~ 65%. For precision mould precision grinding should pay attention to the influence of the environment temperature, constant temperature grinding requirements.Forging die for finishing reserves when rough machining reasonable machining allowance, for a small cushion, may be caused by heat treatment deformation allowance of not enough, we must have a new system for forging die repair, if leave headroom is too large, it increases the difficulty of hardening processing.When forging die coattails "supporting surface and parting surface parallel degree more than requirement, can make the forging die lock gnawing on or cracked, the person that weigh will interrupt hammer stem and even damage hammer, so in forging die processing in the cavity dimension of the request processing according to the drawing, the other part of overall size, location degree, the parallel degree, vertical degree by request processing and strict inspection. Some of small forging die after heat treatment plant with flat grinder grinding up and down the plane, with the goal of large forging die cutting planer generation to shave, ensure manufacturing precision.Forging die cavity directly influence the roughness of the forging die life, roughness high will make forging not easy demould, especially with raised among areas, the deeper the forging, embrace get tight, finally only forging die off with the method of gas cutting machining or damage forgings. Due to the high roughness can make metal flow resistance increased, serious when several pieces will be after the forging die wallwear into groove, not only affects the forming of forgings, also easy to make forging die early failure.Work surface roughness low friction resistance small mould not only, and resistance to bite and anti-fatigue capability is strong, the surface roughness general requirement Ra = 0.4 ~ 0.8 u m.Mould manufacturing assembly precision on the life of die has a very big impact, assembly precision, the underside flat, parallel degree good, the punch and concave die vertical degree is high, the gap even, can also get very high life.精密体积成形模具的设计制造及发展辅助加工技术在生产过程中，提高模具寿命是一个复杂的综合性问题。
机械制造专业外文翻译
附录附录1英文原文Manufacturing EngineeringMultitasking MachiningDone-in-one setup makes parts betterHardened gear wheels (RC 62-65) are rough and finish-turned and finish-ground, drilled, threaded, and broached on an EMAG VSC 250 DS machine.Multifunction machine tools have been around long enough in various configurations for manufacturers to appreciate their potential for cost-saving, quality production of parts from miniature connectors to transmission housings for off-highway equipment. Development of true multitasking machines,however, has removed them from the category of special machines. Manufacturers have made them one of the fastest growing categories of CNC machine tools because they improve competitiveness. They offer the flexibility to meet just-in-time delivery of a variety of parts in smaller lot sizes. They consolidate the processes of many machines, improve accuracy, and save time formerly required for multiple setups as work was moved from machine to machine and operation to operation. Finally, they employ resources of people and capital equipment more efficiently, a definite plus that the most astute accountants can appreciate.The most familiar multitasking machines are NC lathes with live tools in the turret, mill-turns, and Swiss turning centers. NC lathes with a Y axis that allows turrets to move from side to side have full milling or drilling capability. They can mill, drill, and machine off the spindle centerline. A B axis allows rotation around the Y axis for drilling at an angle or contour milling.sand dollars to over a million dollars. That hardly qualifies them as commodity machines; yet, increasingly, these multitasking machines form the backbone of advanced machining operations for everyone from contract manufacturers to OEMs.Trends in the design of multitasking machines include packing more punch into a limited and crowded work area with extra slides, more horsepower, even matching sub spindle horsepower to that of the main spindle, putting more driven tools in the cut at the same time, and developing sophisticated software and controls for collision-avoidance, scheduling, and production analysis. For machine tool manufacturers with extensive experience in building CNC lathes and turningcenters, developing multitasking machines is a natural next step.Romi Machine Tools Ltd. (Erlanger, KY) developed its multitasking E series turning centers to perform turning, boring, milling, and tapping in one setup in a machine with a compact footprint. The E 320 turning center can be configured with one or two spindles,C axis, live tools, and Y axis for mid to high-volume production. The left spindle features a belt-driven cartridge-style gearless headstock with a high-torque 25 or 35-hp (18.6 or 26.1-kW) GE Fanuc AC spindle motor with a variable speed drive.The right spindle can match the left spindle with a similar 25-hp spindle motor. The slant-bed style E 320 series has a swing of 27.55" (700 mm), a maximum cutting length of 23.62" (600 mm), distance between spindle faces of 41.26" (1048 mm) and a cutting diam of 12.6" (320 mm). The E series includes an E 280 model, which features 15-hp (11.1-kW) spindles, as well as a double-turret, double-spindle E 220 model.pressure coolant, air blast, tool touch probe, and part sensor. The Hardinge-designed and built jaw chuck/collet-ready spindle design permits faster spindle speeds for faster cycle times and maximum part rigidity as parts are gripped close to the spindle bearings, resulting in increased concentricity.When equipped with Hardinge's patented HydroGlide hydrostatic linear guideway system, the Quest CNC lathes have the rigidity and precision required for hard turning, as well as the improved crash protection that hydrostatic design offers.The concept of "done in one" rules today, especially as complex parts can be machined from bar stock or from solid, often eliminating the leadtime and expense involved to design and produce castings and forgings. Manufacturers have been quick to recognize and study their potential for maintaining critical tolerances between features by eliminating multiple setups and the time and accuracy lost moving from operation to operation.At its Technical Center, Caterpillar Inc. (Peoria, IL) works in alliance with its machine tool suppliers to evaluate the potential of equipment and processes that can range from prototype work to production for next-generation Caterpillar equipment, according to Jim Reeb, director of manufacturing research and development. Caterpillar is currently working with Cincinnati Lamb's H5 Geminex series machine for machining and turning powertrain components.The H5 Geminex machine is a flexible solution for processing medium-sized and large parts requiring milling and turning in a single setup, combining four and five-axis machining and high-speed turning."We're doing some horizontal types of machining and turning on ductile housings," says Reeb. "We'll develop the process at the Tech Center and once it's worked out, we'll release the machine to our Decatur, IL facility for installation and production."Early experience with the potential of multitasking machine cells led Sandvik Mining and Construction (Sandviken, Sweden) to move production of its DTH (down-the-hole) rock drilling bits from the low-cost manufacturing environment of Mexico to Sweden in 2001. The DTH rock drilling bits are made from alloy steel forging blanks in 200 different types, of which 15 types are most frequently produced in batches varying from eight to 48.Making the move possible was the performance of a multitasking cell featuring three Nakamura STS-40 super multitasking turning centers with robotic workpiece handling. The cell is able to perform all turning, milling, drilling, and button-hole drilling, including a hardening cycle, of the alloy steel DTH drill bits in five days with 12 operators. The previous conventional method required seven machines and 50 people. Standardizing on the Sandvik Coromant Capto interface and selecting twin-edge tooling with two inserts in each toolholder enable each machine to independently perform complete machining of drill bits.The need to be competitive in its manufacturing processes is no less important to a machine tool builder than it is to its customers. In mid-November 2005, at the unveiling of its latest investment in advanced technology at its headquarters and manufacturing facility in Florence, KY, Brian Papke, president, Mazak Corp. said: "It is nae to be committed to manufacturing in the US without a plan to become cost and price competitive."To support production of its Nexus family of machines, many of which have multitasking capabilities, Mazak implemented lean manufacturing practices, including building to market demand rather than forecast and developing modularly assembled systems. A Palletech automation system for "done-in-one" manufacturing was installed. Production capacity for Nexus machines at its Florence facility has risen to 140 machines per month.--------------------------------------------------------------------------------Rotomill MPMC machines can turn, mill (both with B axis and U axis),as well as drill, tap, or hob complex workpieces.--------------------------------------------------------------------------------Manufacturing cells at Mazak's Florence facility feature Integrex multitasking machines produced by parent company, Yamazaki Mazak (Oguchi, Japan). Mazak has installed two Integrex-500HS multitasking machines teamed with robots for part loading and material handling within the flex cells. A large Integrex e-1060 V/8 multitasking center is being integrated with an existing HMC FMS to allow more flexibility in processing medium-sized machine components.In its product mix, Mazak numbers 11 different Integrex multitasking models and another 20 models with some degree of multitasking capability. In recognition of the unique challenges in programming and operation of multitasking machines, Mazak has established a Center for Multi-Tasking and Manufacturing Excellence for training customers in all aspects of multitasking machining at its National Technology Center, which was doubled in size.--------------------------------------------------------------------------------Workpieces as large as these crankshafts, and larger, are completely machinedon WFL's mill-turn centers.--------------------------------------------------------------------------------Following introductions in Japan last summer and at EMO 2005, Mori Seiki U.S.A. Inc. (Irving, TX) introduced its new NT Series of integrated mill-turn centers to the North American market in November. The NT Series is said to be the product of a complete rethinking of the design and construction of the multitasking machine with the goal of integrating milling and turning functions completely to deliver the same performance levels achieved by each process on dedicated machines.The NT Series employs both DCG (Driven at the Center of Gravity) technology and the box-in-box construction of its NH Series horizontal machining centers, along with a turret with a built-in milling motor.The NT Series comprises nine models with spindle, lower turret, and no center support options bringing the total number of variations to 66. NT Series machines have a B axis (?120? that uses a direct drive (DD) motor, eliminating backlash and making high-speed rotation possible. Maximum spindle speed is 5000 rpm with a maximum tool spindle speed of 12,000 rpm.The turret with built-in milling motor first introduced with Mori Seiki's NL Series of CNC lathes reportedly minimizes heat generation and vibration while eliminating transmission losses. The NL CNC lathes are available in four classes and six specification variations. Some 70% of the NL lathes ordered have been equipped with the multitasking capability of the direct-drive milling motor turret.Mori Seiki's MAPPS III control system for fast processing and collision prevention. completely checks for interference in 3-D in real time for spindles, workpieces, soft jaws, tools, holders, and turrets. Component collisions are prevented at all stages from setup to program operation since interference is detected in all automatic and manual modes.General engineering and aerospace contract manufacturers working in difficult-to-machine materials such as titanium, Inconel, and hardened steels are regarded as prime candidates for the M35 and M35-G multitasking models introduced by WFL Millturn Technologies Inc. (Novi, MI) at EMO 2005.The M35 series is the newest and smallest of WFL's product lineup of mill turn centers. The M35 series features a maximum turning diam of 420 mm, workpiece lengths up to 2090 mm, and a total of 92 tools, including the lower turret. WFL's largest mill turns can process workpieces to 6.5-m long, providing multifunctional turning-boring-milling units for complete machining of complex chuck and bar workpieces in one setup.The M35-G delivers high torque and feed forces to get the full potential of tools weighing up to 15 kg and measuring 450-mm long. The 20-kW milling spindle has a maximum torque of 165 N•m above 1100 rpm. Tool change takes place in a fixed and clearly defined position above the left-hand main spindle. The changing device ensures swift replacement and transfer of tools no longer required to the magazine. Tool systems can be HSK-A63, Capto C6, or KM63.To avoid collisions in automatic and manual operation, WFL offers a patented software option called CrashGuard, a real-time software extension of the CNC. Based on an internal 3-D model of the machine, CrashGuard provides realistic modeling of all special functions of the control, such as five-axis interpolation, rotation of coordinates, spline interpolation, and synchronizations, as well as correct and automatic representation of all machine cycles and macros, whether created by the machine manufacturer or the end user.Weing itner Maschinenbau GmbH (Kirchham, Austria) has expanded its Rotomill pick-up whirling/milling machines with the introduction of the Rotomill MPMC (multiproduct machining center). The Rotomill MPMC is equipped with a pick-up, high-power machining head and a five-axis interpolating controller for production of balanced/unbalanced chucking parts and heavy shafts, as well as for box-shaped housing-like components with dimensions up to 1.5-m diam workpiece envelope to 11-m long.Processes such as turning, milling, boring, deep hole drilling, and tapping can be performed on the Rotomill MPMC in a single setup. Virtually any mechanical cutting method can be realized, including turning, milling (both with B and also U axis), as well as drilling, tapping, or hobbing. Applications include production in one setup of extrusion cylinder and feed extruder screws, precision and special tubes for the oilfield industry, large crankshafts, cam shafts, motor housings, aircraft landing gears, and heavy drive shafts for the energy, ship building, and defense industries. Other industries that use the systems include the paper industry, mining, electrical (including turbines), electrical shafts, compressor, and plastics industries.With quality requirements in the mechanical engineering industry and especially the automotive sector becoming increasingly stringent, EMAG LLC (Farmington Hills, MI) has combined hard turning and finish grinding for fast removal of metal and finish machining of parts. The demand for tighter tolerances and expanded machining capabilities requires the complete machining of components in a single setup.EMAG, which offers workpiece-specific solutions for batch production in the automotive, hydraulics, and pneumatics industries, points to the need for multifunctional machines and dry machining, particularly of hardened workpieces. Reasons include ecology, environmental compatibility, and the rapid rise in waste-disposal costs for cutting oils.EMAG,EMAG's VSC DS turning and grinding centers are being used to machine workpieces, such as transmission parts, gearwheels, sliding sleeves, link pins, components for CVT gearboxes, roller races, rocker arms, bearings, and bearing rings. The combination of grinding and hard turning generates the smallest possible amount of heat on the workpiece surface. Rough hard turning is immediately followed by finish grinding without changing setups.The pick-up concept allows the EMAG VSC DS turning and grinding center to load itself just like all the other VSC machines. The machine benefits from thermal stability, as work spindle, grinding spindles, turret, and machine base are all fluid-cooled.中文翻译制造工程学多功能加工中心一次装夹使加工零件性能更好。
机械制造专业外文翻译--机床夹具的分类与构成
外文原文：Machine classification and pose fixture1 fixture in the role of machiningWorkpiece clamping fixture is a kind of process equipment, it is widely used in mechanical machining of the manufacturing process, heat treatment, assembly, welding and testing processes. In the use of metal-cutting machine tools collectively referred to as the jig fixture. n a modern production machine is an indispensable fixture of the process equipment, machining of the workpiece, the processing requirements in order to ensure. First of all to the workpiece and the machine tool relative to a correct position, and this location during processing does not change the impact of external forces. To this end, during the pre-machining, workpiece clamping must be good. There are two ways to clamp workpiece: one is directly clamping the workpiece in the machine table or on the chuck; The other is the workpiece in the fixture on the fixture. The first method used when the workpiece clamping, the general design requirements have to press lines in the surface to draw the size and location, clamping, or when the needle is zoned dial indicator to find is after the clamping. This method need special equipment, but low efficiency, are generally used for one-piece and small batch production. Large quantities, mostly with the workpiece clamping fixture. With the merits of the workpiece clamping fixtures are as follows: (l) Guarantee the stability of the machining accuracy of workpiece. Workpieces with clamping fixture, the workpiece relative to the location of tool and machine tool to ensure the accuracy of the fixture from the technical level of workers, so that a number of workpiece machining accuracy of the line.(2) To improve labor productivity. Workpiece clamping fixture can facilitate the user easily、rapidly, and the workpiece does not need to find is crossed, can significantly reduce the supplementary working hours, to improve labor productivity; workpiece in the fixture after the fixture to improve the rigidity of the workpiece, thus cutting the amount of increase, to improve labor productivity; can use more pieces of multi-workpiece clamping fixture, and the use of efficient clamping bodies, to further improve labor productivity.(3) To expand the use of machine tools. Machine tools in general use a dedicated machine tool fixture can expand the scope of the process and give full play to the potential of machine tools to achieve a multi-machine use. For example, the use of adedicated fixture can be easily Lathe processing small box to the workpiece. Even in the lathe out of oil, a reduction of expensive dedicated machines, reducing the cost, which is particularly important for small and medium-sized factories.(4) To improve the operator's working conditions. As the pneumatic, hydraulic, electro-magnetic power source, such as the application in the fixture, on the one hand to reduce the labor intensity of workers; the other hand, it guarantees the reliability of the workpiece clamping, and to achieve the interlocking machine, to avoid accidents, ensure the operator safety and machine tool equipment(5) To reduce costs. In mass production after the use of fixture, from stem to increase labor productivity, lower level technical workers, as well as lower scrap and other reasons, obviously to reduce the production costs.Fixture manufacturing cost-sharing in a group of workpieces, each workpiece to increase the cost is very minimal, far less than as a result of increased labor productivity and reduce costs. The greater volume of workpiece, fixture made to use has become more significant economic benefits.2 Fixture Category2.1 General characteristics of the fixture by CategoryAccording to the production in different types of fixtures in the common characteristics of machine tool fixture fixture can be divided into general, special fixtures, adjustable clamp, and automatic line of modular fixture fixture, such as: (l) General Fixture. Universal fixture refers to the structure, size has been standardized, and has a certain universal fixture. This type of fixture adaptable, can be used to setup the scope of a certain shape and size of various parts.(2)A dedicated fixture. This type of fixture is designed for a particular part of the processing procedures and the design and manufacture. Relatively stable in the product, the production of larger quantities, used a variety of special fixtures, access to higher productivity and machining accuracy. (3) Adjustable fixture. Adjustable fixture for general fixture and special fixture and the defects developed a new kind of fixture. Of different types and sizes of the workpiece, simply adjust or replace the fixture at the original location of the individual components and will be used to clamp components. （4) Modular Fixture. Modular fixture is a modular fixture. Standard components of the module with high precision and resistance to abrasion, can be assembled into a variety of fixtures. Removable fixture used to clean the assembly after the new fixture left. （5) Automatic line fixture. Automatic line clamp generally divided into two categories:fixed-type fixture, which is similar to a dedicated fixture; other accompanying a fixture for the use of the workpiece in the fixture, together with the movement, and automatic workpiece along the line from a move to the next position position for processing.2.2 Classification by the use of machine tools ClassificationBy the use of machine tools can be divided into lathe jig fixtures, milling fixtures, drilling fixtures, hang-bed fixture, jig gear machine, CNC machine tool fixture, automatic machine tool fixtures, accompanied by automatic line, and other fixtures, such as machine tools. This is a special fixture design of the classification method used. Dedicated fixture design, the machine group, the type and the main parameters have been determined. Their difference is the cutting forming machine tool movements, so the connection fixture with the machine in different ways. Machining accuracy of their different requirements.2.3 Clamping fixture according to the power sourceClamping fixture according to the power source can be divided into manual fixture, pneumatic fixtures, hydraulic fixtures, gas fixtures by force, electromagnetic fixture, vacuum fixtures, fixture, such as centrifugal force.3 the composition of fixtureAlthough the structure of machine tool fixture range, but their components can be summarized as the following sections.(1) Positioning components. Typically, when the shape of the workpiece datum position established, the position will be the basic components of the structure identified(2) Clamping device. Positioning of the workpiece in the fixture, the need to clamp the workpiece before processing to ensure that the workpiece during processing is not due to external force and undermine its position.(3) The specific folder. Fixture and the skeleton matrix, all the components through the fixture it will constitute a whole.(4) Of the knife or the guide. Tool used to determine position relative to the correct position of components. Of the knife device common in milling fixture. Used to adjust the cutter knife block position before machining.(5) To connect components. Connected components in the machine tool fixture is todetermine the correct position on the component, therefore, can double as a specific folder to connect components. Lathe fixture on the transition plate, the positioning ofmilling machine fixture on key components are connected.(6) Other devices or components. According to the processing needs, some degree fixture device were used by mode device, the whole device, and the balance of the top block and so on. These components or devices specially designed need.中文译文：机床夹具的分类与构成1机床夹具在机械加工中的作用夹具是一种装夹工件的工艺装备，它广泛地应用于机械制造过程的切削加工、热处理、装配、焊接和检测等工艺过程中。
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编号：毕业设计(论文)外文翻译（原文）学院：机电工程学院专业：机械设计制造及其自动化学生姓名：***学号： **********指导教师单位：机电工程学院指导老师：***职称：副教授2016年 6 月 1 日资料来源：文章名：INTEGRATION OF MACHINERY书刊名：《Digital Image Processing》作者：Y. Torres, J. J. Pavón, I. Nieto and J. A. Rodríguez出版社：武汉大学出版社，2004章节：2.4 INTEGRATION OF MACHINERY页码：P15～P18INTEGRATION OF MACHINERY（From ELECTRICAL AND MACHINERY INDUSTRY）ABSTRACTMachinery was the modern science and technology development inevitable result, this article has summarized the integration of machinery technology basic outline and the development background .Summarized the domestic and foreign integration of machinery technology present situation, has analyzed the integration of machinery technology trend of development.Key word：integration of machinery ，technology，present situation ，product t，echnique of manufacture ，trend of development0. Introduction modern science and technology unceasing development, impelled different discipline intersecting enormously with the seepage, has caused the project domain technological revolution and the transformation .In mechanical engineering domain, because the microelectronic technology and the computer technology rapid development and forms to the mechanical industry seepage the integration of machinery, caused the mechanical industry the technical structure, the product organization, the function and the constitution, the production method and the management system has had the huge change, caused the industrial production to enter into "the integration of machinery" by "the machinery electrification" for the characteristic development phase.1. Integration of machinery outline integration of machinery is refers in the organization new owner function, the power function, in the information processing function and the control function introduces the electronic technology, unifies the system the mechanism and the computerization design and the software which constitutes always to call. The integration of machinery development also has become one to have until now own system new discipline, not only develops along with the science and technology, but also entrusts with the new content .But its basic characteristic may summarize is: The integration of machinery is embarks from the system viewpoint, synthesis community technologies and so on utilization mechanical technology, microelectronic technology, automatic control technology, computer technology, information technology, sensing observation and control technology, electric power electronic technology, connection technology, information conversion technology as well as software programming technology, according to the system function goal and the optimized organization goal, reasonable disposition and the layout various functions unit, in multi-purpose, high grade, redundant reliable, in the low energy consumption significance realize the specific function value, and causes the overall system optimization the systems engineering technology .From this produces functional system, then becomes an integration of machinery systematic or the integration of machinery product. Therefore, "integration of machinery" covering "technology" and "product" two aspects .Only is, the integration of machinery technology is based on the above community technology organic fusion one kind of comprehensive technology, but is not mechanical technical, the microelectronic technology as well as other new technical simple combination, pieces together .This is the integration of machinery and the machinery adds the machinery electrification which the electricity forms in the concept basic difference .The mechanical engineering technology has the merely technical to develop the machinery electrification, still was the traditional machinery, its main function still was replaces with the enlargement physical strength .But after develops the integration of machinery, micro electron installment besides may substitute for certain mechanical parts the original function, but also can entrust with many new functions, like the automatic detection, the automatic reduction information, demonstrate the record, the automatic control and the control automatic diagnosis and the protection automatically and so on .Not only namely the integration of machinery product is human's hand and body extending, human's sense organ and the brains look, has theintellectualized characteristic is the integration of machinery and the machinery electrification distinguishes in the function essence.2. Integration of machinery development condition integration of machinery development may divide into 3 stages roughly.20th century 60's before for the first stage, this stage is called the initial stage .In this time, the people determination not on own initiative uses the electronic technology the preliminary achievement to consummate the mechanical product the performance .Specially in Second World War period, the war has stimulated the mechanical product and the electronic technology union, these mechanical and electrical union military technology, postwar transfers civilly, to postwar economical restoration positive function .Developed and the development at that time generally speaking also is at the spontaneous condition .Because at that time the electronic technology development not yet achieved certain level, mechanical technical and electronic technology union also not impossible widespread and thorough development, already developed the product was also unable to promote massively. The 20th century 70~80 ages for the second stage, may be called the vigorous development stage .This time, the computer technology, the control technology, the communication development, has laid the technology base for the integration of machinery development . Large-scale, ultra large scale integrated circuit and microcomputer swift and violent development, has provided the full material base for the integration of machinery development .This time characteristic is :①A mechatronics word first generally is accepted in Japan, probably obtains the quite widespread acknowledgment to 1980s last stages in the worldwide scale ;②The integration of machinery technology and the product obtained the enormous development ;③The various countries start to the integration of machinery technology and the product give the very big attention and the support. 1990s later periods, started the integration of machinery technology the new stage which makes great strides forward to the intellectualized direction, the integration of machinery enters the thorough development time .At the same time, optics, the communication and so on entered the integration of machinery, processes the technology also zhan to appear tiny in the integration of machinery the foot, appeared the light integration of machinery and the micro integration of machinery and so on the new branch; On the other hand to the integration of machinery system modeling design, the analysis and the integrated method, the integration of machinery discipline system and thetrend of development has all conducted the thorough research .At the same time, because the hugeprogress which domains and so on artificial intelligence technology, neural network technology and optical fiber technology obtain, opened the development vast world for the integration of machinery technology .These research, will urge the integration of machinery further to establish the integrity the foundation and forms the integrity gradually the scientific system. Our country is only then starts from the beginning of 1980s in this aspect to study with the application .The State Council had been established the integration of machinery leading group and lists as "863 plans" this technology .When formulated "95" the plan and in 2010 developed the summary had considered fully on international the influence which and possibly brought from this about the integration of machinery technology development trend .Many universities, colleges and institutes, the development facility and some large and middle scale enterprises have done the massive work to this technical development and the application, does not yield certain result, but and so on the advanced countries compared with Japan still has the suitable disparity.3. Integration of machinery trend of development integrations of machinery are the collection machinery, the electron, optics, the control, the computer, the information and so on the multi-disciplinary overlapping syntheses, its development and the progress rely on and promote the correlation technology development and the progress .Therefore, the integration of machinery main development direction is as follows:3.1 Intellectualized intellectualizations are 21st century integration of machinery technological development important development directions .The artificial intelligence obtains day by day in the integration of machinery constructor's research takes, the robot and the numerical control engine bed intellectualization is the important application .Here said "the intellectualization" is to the machine behavior description, is in the control theory foundation, the absorption artificial intelligence, the operations research, the computer science, the fuzzy mathematics, the psychology, the physiology and the chaos dynamics and so on the new thought, the new method, simulate the human intelligence, enable it to have abilities and so on judgment inference, logical thinking, independent decision-making, obtains the higher control goal in order to .Indeed, enable the integration of machinery product to have with the human identical intelligence, is not impossible, also is nonessential .But, the highperformance, the high speed microprocessor enable the integration of machinery product to have preliminary intelligent or human's partial intelligences, then is completely possible and essential.In the modern manufacture process, the information has become the control manufacture industry the determining factor, moreover is the most active actuation factor .Enhances the manufacture system information-handling capacity to become the modern manufacture science development a key point .As a result of the manufacture system information organization and structure multi-level, makes the information the gain, the integration and the fusion presents draws up the character, information measure multi-dimensional, as well as information organization's multi-level .In the manufacture information structural model, manufacture information uniform restraint, dissemination processing and magnanimous data aspects and so on manufacture knowledge library management, all also wait for further break through.Each kind of artificial intelligence tool and the computation intelligence method promoted the manufacture intelligence development in the manufacture widespread application .A kind based on the biological evolution algorithm computation intelligent agent, in includes thescheduling problem in the combination optimization solution area of technology, receives the more and more universal attention, hopefully completes the combination optimization question when the manufacture the solution speed and the solution precision aspect breaks through the question scale in pairs the restriction .The manufacture intelligence also displays in: The intelligent dispatch, the intelligent design, the intelligent processing, the robot study, the intelligent control, the intelligent craft plan, the intelligent diagnosis and so on are variousThese question key breakthrough, may form the product innovation the basic research system. Between 2 modern mechanical engineering front science different science overlapping fusion will have the new science accumulation, the economical development and society's progress has had the new request and the expectation to the science and technology, thus will form the front science .The front science also has solved and between the solution scientific question border area .The front science has the obvious time domain, the domain and the dynamic characteristic .The project front science distinguished in the general basic science important characteristic is it has covered the key science and technology question which the project actual appeared.Manufacture system is a complex large-scale system, for satisfies the manufacture system agility, the fast response and fast reorganization ability, must profit from the information science, the life sciences and the social sciences and so on the multi-disciplinary research results, the exploration manufacture system new architecture, the manufacture pattern and the manufacture system effective operational mechanism .Makes the system optimization the organizational structure and the good movement condition is makes the system modeling , the simulation and the optimized essential target .Not only the manufacture system new architecture to makes the enterprise the agility and may reorganize ability to the demand response ability to have the vital significance, moreover to made the enterprise first floor production equipment the flexibility and may dynamic reorganization ability set a higher request .The biological manufacture view more and more many is introduced the manufacture system, satisfies the manufacture system new request.The study organizes and circulates method and technique of complicated system from the biological phenomenon, is a valid exit which will solve many hard nut to cracks that manufacturing industry face from now on currently .Imitating to living what manufacturing point is mimicry living creature organ of from the organization, from match more, from growth with from evolution etc. function structure and circulate mode of a kind of manufacturing system and manufacturing process.The manufacturing drives in the mechanism under, continuously by one's own perfect raise on organizing structure and circulating mode and thus to adapt the process of[with] ability for the environment .For from descend but the last product proceed together a design and make a craft rules the auto of the distance born, produce system of dynamic state reorganization and product and manufacturing the system tend automatically excellent provided theories foundation and carry out a condition .Imitate to living a manufacturing to belong to manufacturing science and life science of\"the far good luck is miscellaneous to hand over\", it will produce to the manufacturing industry for 21 centuries huge of influence .翻译机电一体化摘要机电一体化是现代科学技术发展的必然结果,本文简述了机电一体化技术的基本概要和发展背景。