机械外文文献翻译

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机械专业外文文献翻译

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。

先进制造技术的新发展——机械类外文文献翻译、中英文翻译

先进制造技术的新发展——机械类外文文献翻译、中英文翻译

外文原文:The new advanced manufacturing technology developmentAbstract : This paper has presented the problems facing today's manufacturing technology, advanced manufacturing discussed in the forefront of science, and a vision for the future development of advanced manufacturing technology.Keyword:Advanced manufacturing technologies; Frontier science; Applications prospectsModern manufacturing is an important pillar of the national economy and overall national strength and its GDP accounted for a general national GDP 20%~55%. In the composition of a country's business productivity, manufacturing technology around 60% of the general role. Experts believe that the various countries in the world economic competition, mainly manufacturing technology competition. Their competitiveness in the production of the final product market share. With the rapid economic and technological development and customer needs and the changing market environment, this competition is becoming increasingly fierce, and that Governments attach great importance to the advanced manufacturing technology research.1 .Current manufacturing science to solve problemsManufacturing science to solve the current problems focused on the following aspects :(1) Manufacturing systems is a complex systems, and manufacturing systems to meet both agility, rapid response and rapid reorganization of the capacity to learn from the information science, life science and social science interdisciplinary research, and explore new manufacturing system architecture, manufacturing models and manufacturing systems effective operational mechanism. Manufacturing systems optimized organizational structure and good performance is manufacturing system modelling, simulation and optimization of the main objectives. Manufacturing system architecture not only to create new enterprises both agility and responsiveness to theneeds and the ability to reorganize significance, but also for the soft production equipment manufacturing enterprises bottom reorganization and dynamic capacity to set higher demands. Biological manufacturing outlook increasingly being introduced to the system to meet new demands manufacturing systems.(2) The rapid rise in support of manufacturing, geometric knowledge sharing has become a modern manufacturing constraints, product development and manufacturing technologies of the key issues. For example, in computer-aided design and manufacturing (CAD/CAM) integration, coordinates measurements (CMM) and robotics fields, in 3D real space (3-Real Space), there are a lot of geometric algorithm design and analysis, especially the geometric said, geometric calculation and geometric reasoning; In measurement and robot path planning and parts search spaces (such as Localization), the existence of space C- interspace (configuration space Configuration Space) geometric calculation and geometric reasoning; Objects in operation (rescue, paying and assembly, etc.) means paying more description and robot planning, campaign planning and assembly operations planning is needed in the types of space (Screw Space) geometric reasoning. Manufacturing process of physical and geometric mechanics phenomenon of scientific research to create a geometric calculation and geometric reasoning, and other aspects of the research topic, the theory pending further breakthrough, the new one door disciplines -- computer geometric are being increasingly broad and in-depth study.(3) In the modern manufacturing process, information not only manufacturing industries have become dominated the decisive factor, but also the most active ones. Manufacturing information systems to improve throughput of modern manufacturing has become a focus of scientific development. The manufacturing information system organization and structure required to create information access, integration and integration show three-dimensional in nature, measuring the multidimensional nature of the information, and information organizations nature. Information structure models in the manufacturing, manufacturing information consistency constraint, and the dissemination of data processing and the manufacture of enormous knowledge base management, and other areas, there is a need to further breakthroughs.(4) The calculation of the wisdom of artificial intelligence tools and methods in the manufacture of a wide range of applications for manufacturing smart development. Category based on the calculation of biological evolution algorithms smart tools, including activation issues optimize GPS technology portfolio by growing concern is in the manufacture of the complete portfolio optimization problems combined speed and precision of GPS issues both in size constraints. Manufacturing wisdom manifested in the following aspects : wisdom activation, wisdom design, intelligent processing, robotics, intelligent control, intelligent process planning, smart diagnostic, and other aspects. These innovative products are the key theoretical issues, but also by creating a door for a science skills in the important basic issues. The focus in these issues, we can form the basis of product innovation research system.2. Modern mechanical engineering at the frontiers of scienceCross-integration between the different science will produce new scientific gathering, economic development and social progress of science and technology created new demands and expectations, thus creating a frontier science. Frontier science is settled and unsettled issues between the scientific community. Frontier science, with a clear domain, and dynamic character of the area. Works frontier science from the general basic science is an important characteristic of the actual works, it covers the key emerging science and technology issues. Ultrasonic electrical, ultra-high-speed machines, green design and manufacturing, and other fields, and has done a lot of research work, but innovation is the key question is not clear mechanical science. Large complex mechanical system design and performance optimization of product innovation design, smart structures and systems, intelligent robots and their dynamics, nano Mocaxue, manufacturing process 3D numerical simulations and physical simulation, precision and ultra-fine processing technology key basis, about 10 mega large and sophisticated equipment design and manufacturing base, virtual manufacturing and virtual instruments, nanometer measurement and instrumentation, parallel connection axis machine tools, and although the field of micro-electromechanical systems have done a lot of research, but there are still many key science and technology issues to be resolved. Information science, nanoscience, materials science, life science, management science and manufacturing science of the 21st century will be to change the mainstream science, and the resulting high-tech industry will change the face of the world. Therefore, the above areas of cross-development manufacturing systems and manufacturing informatics, nano manufacturing machinery and nano science, better machinery and better manufacturing science, management science and manufacturing systems will be critical to the 21st century mechanical engineering science is important frontier science.2.1 Manufacturing science and information science cross -- manufacturing informaticsMechanical and electrical products, chemical raw materials in the information. Many modern value added products primarily reflected in the information. Thus the manufacturing process for the acquisition and application of information is very important. Information science and technology is to create an important symbol of globalization and modernization. While the manufacturing technology began to explore product design and manufacturing processes, the nature of the information, on the other hand, to create technology to transform itself to adapt to the new information makes its manufacturing environment. Along with the manufacturing process and manufacturing systems to deepen understanding, researchers are trying to new concepts and approaches to their description and expression to achieve further control and optimization purposes.And manufacturing-related information mainly product information, technical information and information management in this area following major research direction and content :(1) manufacturing information acquisition, processing, storage, transmission and application of knowledge to create information and decision-making transformation.(2) Non-symbols expressing information, manufacturing information enables transmission, manufacturing information management, manufacturing information integrity in a state of non-production decision-making, management of virtual manufacturing, based on the network environment of the design and manufacturing,manufacturing process control and manufacturing systems science. These elements are manufactured in science and the scientific basis for the integration of product information, constitute the manufacture of the new branch of science -- to create informatics.2.2 Micro mechanical and manufacturing technology researchMicro-electronic mechanical systems (MEMS) refers to the collection of micro-sensors, micro-devices and the implementation of signal processing and control circuits, interface circuits, communications and power with the integration of micro-electromechanical system integrity. MEMS technology objectives through system miniaturization, to explore a new theory of integration, new functional components and systems. MEMS development will greatly facilitate the pocket of various products, miniaturization, a number of devices and systems to enhance the level of functional density, information density and Internet density, significantly saving, thin section. Not only can it reduce the cost of mechanical and electrical systems, but also to be completed and the size of many large systems impossible task. For example, using sophisticated 5μm diameter micro tweezers walls are made of a red blood cell can; Created to keep the cars 3mm size; In the magnetic field, like butterflies flying size aircraft. MEMS technology has opened up a completely new technology areas and industries, with many traditional sensors incomparable advantages in manufacturing, aerospace, transportation, telecommunications, agriculture, biomedical, environmental monitoring, military, families, and access to almost all areas have very broad application prospects.Micro machinery is machinery and electronic technology in nano-scale technology integration photogenic product. Back in 1959 scientists have raised the idea of micro-mechanical and micro-1962, the first silicon pressure sensors. 1987 California University of California Berkeley developed rotor diameter of the silicon micro-60~120 16ug m electrostatic electric motors, show produced using silicon micro-machining small movable structures and compatible with IC manufacturing micro system potential. Micro-mechanical technology might like 20th century microelectronics technology, the technology of the world in the 21st century,economic development and national defense building a tremendous impact. Over the past 10 years, the development of micro-mechanical spectacular. Its characteristics are as follows : a considerable number of micro-components (micro structure, the implementation of micro-sensors and micro-machines, etc.) and micro-systems research success reflects the current and potential applications of value; The development of micro-manufacturing technology, particularly semiconductor processing technology have become small micro systems support technology; micro-electromechanical systems research needs of the interdisciplinary research team, micro-electromechanical systems technology in the development of microelectronics technology on the basis of multidisciplinary cross-frontier area of research, involving electronic engineering, mechanical engineering, materials engineering, physics, chemistry and biomedical engineering and other technical and scientific.The current micro-mechanical systems under the conditions of the campaign laws, the physical characteristics and micro components of the role of the mechanics payload acts lack adequate understanding is not yet in a theoretical basis for a micro-system design theory and methodology, and therefore can By experience and test methods research. Micro-mechanical systems, the existence of key scientific research issues of micro-scale system effects, physical properties and biochemical characteristics. Micro-system research are in the eve of a breakthrough, which is the in-depth study of the area.2.3 Material produced / manufactured parts integration of new technologies for processing.Material is a milestone in the progress of mankind, is the manufacturing and high-tech development. Every important to the success of the production and application of new materials, will promote the material and the promotion of national economic strength and military strength. 21, the world will be resource consumption-based economy to a knowledge-based industrial transformation for materials and parts and functions of a high performance, intelligent features; Request materials and components designed to achieve quantitative-based and digitized; Prepare materials and components for the rapid, efficient and achieve both integrationand integrated. Digital materials and components designed to be a simulation and optimization of materials and components to achieve high quality production / manufacturing and other integration, integrated manufacturing key. On the one hand, to be completed through computer simulation optimization can reduce the material is produced in the course of manufacture of spare parts and experimental links to the best craft programmes, materials and components to achieve high quality production / manufacturing; On the other hand, according to the requirements of different material properties, such as flexible modules volume, thermal expansion coefficient, magnetic performance, Research materials and components designed form. And the removal of traditional materials-manufacturing technology, and increase the level of information technology, the research group of synthetic materials is a process technology. Forming materials and components manufacture digital theory, technology and methods, such as rapid adoption of emerging technologies material growing principles, a breakthrough in the traditional law and to build law mechanical deformation processing many restrictions, no processing tools or dies, can rapidly create arbitrary complex shape and has a certain function 3D models or entity parts.2.4 machinery manufacturing breakthroughThe 21st century will be the century of life science, mechanical and life sciences depth integration will generate new concept products (such as better intelligence structure), to develop a new process (such as the growth processes shape) and the opening of new industries and to resolve product design, manufacturing processes and systems provide a series of problems new solutions. This is a highly innovative and leading edge area in the challenge.Earth's biological evolution in the long accumulated fine qualities of human manufacturing activities to address the various problems with examples and guidelines. Learning from life phenomena organizations operating complex systems and methods and techniques, manufacturing is the future solution to the current problems facing many an efficient way. Better manufacturing refers to the replication of biological organs from organizations, since healing, self growth and evolution since the function of the model structure and operation of a manufacturing system andmanufacturing process. If the manufacturing process mechanization, automation extends human physical and intelligent extension of the human intellectual, then "create better" may be said to extend its own organizational structure and human evolution process.Gene involved in the manufacture of biological science is the "self-organization" mechanism and its application in manufacturing systems. The so-called "self-organization" refers to a system in its internal mechanism driven by the organizational structure and operation mode learning, thereby enhancing the capacity for environmental adaptation process. Create better "since the organization" bottom-up mechanism for parallel product design and manufacturing processes of automatic generation, the dynamics of production systems and manufacturing systems and products more automatic a theoretical foundation and achieve superior conditions.Create a better manufacturing and life sciences "far edge hybrid" of the 21st century manufacturing will have an enormous impact. Create better research content is twofold :2.4.1 To create better livesResearch lives of the general phenomenon of the law and models, such as artificial life, cellular automatic machines, biological information processing skills, biological wisdom, biological-based organizational structure and mode of operation and the evolution of biological mechanisms and getting better;2.4.2 Oriented manufacturing breakthrough manufacturingResearch organizations better manufacturing systems since the mechanisms and methods, for example : based on full information-sharing breakthrough design principles, multi-discipline modules based on the distributed control and coordination mechanism based on the evolution of an excellent strategy; Study the concept of creating better system and its basis, such as : the formalization described space and better information shine upon relations better system and its evolution of complexity measurement methods.Machinery manufacturing is better and better mechanical science and life science, information science, materials science disciplines such as high integration, the studyincludes growth formative processes, better design and manufacturing systems, mechanical and biological wisdom better shape manufacturing. Currently doing research mostly forward exploratory work, with distinct characteristics of the basic research, if the research continues to seize opportunities that might arise revolutionary breakthroughs. Future research should concern areas of biological processing technology, better manufacturing system, based on rapid prototype manufacturing engineering technology organizations, as well as biological engineering related key technical basis.3. Modern manufacturing technology trendsSince the beginning of the 1990s, the nations of the world have manufacturing technology research and development as a national priority for the development of key technologies, such as the United States advanced manufacturing technology plan AMTP, Japan wisdom manufacturing technology (IMS) international cooperation schemes, Korea senior national plan of modern technology (G--7), Germany plans to manufacture 2000 and the EC Esprit and BRITE-EURAM plan.With the electronics, information, the constant development of new and high technologies, market demand individuality and diversity, the future of modern manufacturing technology to the overall development trends of the sophisticated, flexible, and networked, virtual and intelligent, green integrated, globalization direction.Current trends in modern manufacturing technology has the following nine areas :(1) Information technology, management techniques and technology closelyintegrated technology, modern production model will be continuous development.(2) Design techniques and more modern means.(3) Shaped and manufacture of sophisticated technology and manufacturingprocesses to achieve longer.(4) The formation of new special processing methods.(5) Development of a new generation of ultra-sophisticated, ultra-high-speedmanufacturing equipment.(6) Machining skills development for the engineering sciences.(7) Implementation of clean green manufacturing.(8)The widespread application of virtual reality technology to the manufacturingsector.(9) To create people-oriented.译文:先进制造技术的新发展摘要:本文介绍了当今制造技术面临的问题,论述了先进制造的前沿科学,并展望了先进制造技术的发展前景。

机械手臂外文文献翻译、中英文翻译、外文翻译

机械手臂外文文献翻译、中英文翻译、外文翻译

外文出处:《Manufacturing Engineering and Technology—Machining》附件1:外文原文ManipulatorRobot developed in recent decades as high-tech automated production equipment. I ndustrial robot is an important branch of industrial robots. It features can be program med to perform tasks in a variety of expectations, in both structure and performance a dvantages of their own people and machines, in particular, reflects the people's intellig ence and adaptability. The accuracy of robot operations and a variety of environments the ability to complete the work in the field of national economy and there are broad p rospects for development. With the development of industrial automation, there has be en CNC machining center, it is in reducing labor intensity, while greatly improved lab or productivity. However, the upper and lower common in CNC machining processes material, usually still use manual or traditional relay-controlled semi-automatic device . The former time-consuming and labor intensive, inefficient; the latter due to design c omplexity, require more relays, wiring complexity, vulnerability to body vibration inte rference, while the existence of poor reliability, fault more maintenance problems and other issues. Programmable Logic Controller PLC-controlled robot control system for materials up and down movement is simple, circuit design is reasonable, with a stron g anti-jamming capability, ensuring the system's reliability, reduced maintenance rate, and improve work efficiency. Robot technology related to mechanics, mechanics, elec trical hydraulic technology, automatic control technology, sensor technology and com puter technology and other fields of science, is a cross-disciplinary integrated technol ogy.First, an overview of industrial manipulatorRobot is a kind of positioning control can be automated and can be re-programmed to change in multi-functional machine, which has multiple degrees of freedom can be used to carry an object in order to complete the work in different environments. Low wages in China, plastic products industry, although still a labor-intensive, mechanical hand use has become increasingly popular. Electronics and automotive industries thatEurope and the United States multinational companies very early in their factories in China, the introduction of automated production. But now the changes are those found in industrial-intensive South China, East China's coastal areas, local plastic processin g plants have also emerged in mechanical watches began to become increasingly inter ested in, because they have to face a high turnover rate of workers, as well as for the workers to pay work-related injuries fee challenges.With the rapid development of China's industrial production, especially the reform and opening up after the rapid increase in the degree of automation to achieve the wor kpiece handling, steering, transmission or operation of brazing, spray gun, wrenches a nd other tools for processing and assembly operations since, which has more and mor e attracted our attention. Robot is to imitate the manual part of the action, according to a given program, track and requirements for automatic capture, handling or operation of the automatic mechanical devices.In real life, you will find this a problem. In the machine shop, the processing of part s loading time is not annoying, and labor productivity is not high, the cost of producti on major, and sometimes man-made incidents will occur, resulting in processing were injured. Think about what could replace it with the processing time of a tour as long a s there are a few people, and can operate 24 hours saturated human right? The answer is yes, but the robot can come to replace it.Production of mechanical hand can increase the automation level of production and labor productivity; can reduce labor intensity, ensuring product quality, to achieve saf e production; particularly in the high-temperature, high pressure, low temperature, lo w pressure, dust, explosive, toxic and radioactive gases such as poor environment can replace the normal working people. Here I would like to think of designing a robot to be used in actual production.Why would a robot designed to provide a pneumatic power: pneumatic robot refers to the compressed air as power source-driven robot. With pressure-driven and other en ergy-driven comparison have the following advantages: 1. Air inexhaustible, used late r discharged into the atmosphere, does not require recycling and disposal, do not pollu te the environment. (Concept of environmental protection) 2. Air stick is small, the pipeline pressure loss is small (typically less than asphalt gas path pressure drop of one-thousandth), to facilitate long-distance transport. 3. Compressed air of the working pre ssure is low (usually 4 to 8 kg / per square centimeter), and therefore moving the mate rial components and manufacturing accuracy requirements can be lowered. 4. With th e hydraulic transmission, compared to its faster action and reaction, which is one of th e advantages pneumatic outstanding. 5. The air cleaner media, it will not degenerate, n ot easy to plug the pipeline. But there are also places where it fly in the ointment: 1. A s the compressibility of air, resulting in poor aerodynamic stability of the work, resulti ng in the implementing agencies as the precision of the velocity and not easily control led. 2. As the use of low atmospheric pressure, the output power can not be too large; i n order to increase the output power is bound to the structure of the entire pneumatic s ystem size increased.With pneumatic drive and compare with other energy sources drive has the followin g advantages:Air inexhaustible, used later discharged into the atmosphere, without recycling and disposal, do not pollute the environment. Accidental or a small amount of leakage wo uld not be a serious impact on production. Viscosity of air is small, the pipeline pressu re loss also is very small, easy long-distance transport.The lower working pressure of compressed air, pneumatic components and therefor e the material and manufacturing accuracy requirements can be lowered. In general, re ciprocating thrust in 1 to 2 tons pneumatic economy is better.Compared with the hydraulic transmission, and its faster action and reaction, which is one of the outstanding merits of pneumatic.Clean air medium, it will not degenerate, not easy to plug the pipeline. It can be saf ely used in flammable, explosive and the dust big occasions. Also easy to realize auto matic overload protection.Second, the composition, mechanical handRobot in the form of a variety of forms, some relatively simple, some more complic ated, but the basic form is the same as the composition of the , Usually by the implem enting agencies, transmission systems, control systems and auxiliary devices composed.1.Implementing agenciesManipulator executing agency by the hands, wrists, arms, pillars. Hands are crawlin g institutions, is used to clamp and release the workpiece, and similar to human finger s, to complete the staffing of similar actions. Wrist and fingers and the arm connecting the components can be up and down, left, and rotary movement. A simple mechanical hand can not wrist. Pillars used to support the arm can also be made mobile as needed .2. TransmissionThe actuator to be achieved by the transmission system. Sub-transmission system c ommonly used manipulator mechanical transmission, hydraulic transmission, pneuma tic and electric power transmission and other drive several forms.3. Control SystemManipulator control system's main role is to control the robot according to certain p rocedures, direction, position, speed of action, a simple mechanical hand is generally not set up a dedicated control system, using only trip switches, relays, control valves a nd circuits can be achieved dynamic drive system control, so that implementing agenc ies according to the requirements of action. Action will have to use complex program mable robot controller, the micro-computer control.Three, mechanical hand classification and characteristicsRobots are generally divided into three categories: the first is the general machinery does not require manual hand. It is an independent not affiliated with a particular host device. It can be programmed according to the needs of the task to complete the oper ation of the provisions. It is characterized with ordinary mechanical performance, also has general machinery, memory, intelligence ternary machinery. The second category is the need to manually do it, called the operation of aircraft. It originated in the atom, military industry, first through the operation of machines to complete a particular job, and later developed to operate using radio signals to carry out detecting machines suc h as the Moon. Used in industrial manipulator also fall into this category. The third cat egory is dedicated manipulator, the main subsidiary of the automatic machines or automatic lines, to solve the machine up and down the workpiece material and delivery. T his mechanical hand in foreign countries known as the "Mechanical Hand", which is t he host of services, from the host-driven; exception of a few outside the working proc edures are generally fixed, and therefore special.Main features:First, mechanical hand (the upper and lower material robot, assembly robot, handlin g robot, stacking robot, help robot, vacuum handling machines, vacuum suction crane, labor-saving spreader, pneumatic balancer, etc.).Second, cantilever cranes (cantilever crane, electric chain hoist crane, air balance th e hanging, etc.)Third, rail-type transport system (hanging rail, light rail, single girder cranes, doubl e-beam crane)Four, industrial machinery, application of handManipulator in the mechanization and automation of the production process develo ped a new type of device. In recent years, as electronic technology, especially comput er extensive use of robot development and production of high-tech fields has become a rapidly developed a new technology, which further promoted the development of ro bot, allowing robot to better achieved with the combination of mechanization and auto mation.Although the robot is not as flexible as staff, but it has to the continuous duplication of work and labor, I do not know fatigue, not afraid of danger, the power snatch weig ht characteristics when compared with manual large, therefore, mechanical hand has b een of great importance to many sectors, and increasingly has been applied widely, for example:(1) Machining the workpiece loading and unloading, especially in the automatic lat he, combination machine tool use is more common.(2) In the assembly operations are widely used in the electronics industry, it can be used to assemble printed circuit boards, in the machinery industry It can be used to ass emble parts and components.(3) The working conditions may be poor, monotonous, repetitive easy to sub-fatigue working environment to replace human labor.(4) May be in dangerous situations, such as military goods handling, dangerous go ods and hazardous materials removal and so on..(5) Universe and ocean development.(6), military engineering and biomedical research and testing.Help mechanical hands: also known as the balancer, balance suspended, labor-saving spreader, manual Transfer machine is a kind of weightlessness of manual load system, a novel, time-saving technology for material handling operations booster equipment, belonging to kinds of non-standard design of series products. Customer application ne eds, creating customized cases. Manual operation of a simulation of the automatic ma chinery, it can be a fixed program draws ﹑ handling objects or perform household to ols to accomplish certain specific actions. Application of robot can replace the people engaged in monotonous ﹑ repetitive or heavy manual labor, the mechanization and a utomation of production, instead of people in hazardous environments manual operati on, improving working conditions and ensure personal safety. The late 20th century, 4 0, the United States atomic energy experiments, the first use of radioactive material ha ndling robot, human robot in a safe room to manipulate various operations and experi mentation. 50 years later, manipulator and gradually extended to industrial production sector, for the temperatures, polluted areas, and loading and unloading to take place t he work piece material, but also as an auxiliary device in automatic machine tools, ma chine tools, automatic production lines and processing center applications, the comple tion of the upper and lower material, or From the library take place knife knife and so on according to fixed procedures for the replacement operation. Robot body mainly b y the hand and sports institutions. Agencies with the use of hands and operation of obj ects of different occasions, often there are clamping ﹑ support and adsorption type of care. Movement organs are generally hydraulic pneumatic ﹑﹑ electrical device dri vers. Manipulator can be achieved independently retractable ﹑ rotation and lifting m ovements, generally 2 to 3 degrees of freedom. Robots are widely used in metallurgic al industry, machinery manufacture, light industry and atomic energy sectors.Can mimic some of the staff and arm motor function, a fixd procedure for the capture, handling objects or operating tools, automatic operation device. It can replace hum an labor in order to achieve the production of heavy mechanization and automation th at can operate in hazardous environments to protect the personal safety, which is wide ly used in machinery manufacturing, metallurgy, electronics, light industry and nuclea r power sectors. Mechanical hand tools or other equipment commonly used for additio nal devices, such as the automatic machines or automatic production line handling an d transmission of the workpiece, the replacement of cutting tools in machining centers , etc. generally do not have a separate control device. Some operating devices require direct manipulation by humans; such as the atomic energy sector performs household hazardous materials used in the master-slave manipulator is also often referred to as m echanical hand.Manipulator mainly by hand and sports institutions. Task of hand is holding the wor kpiece (or tool) components, according to grasping objects by shape, size, weight, mat erial and operational requirements of a variety of structural forms, such as clamp type, type and adsorption-based care such as holding. Sports organizations, so that the com pletion of a variety of hand rotation (swing), mobile or compound movements to achie ve the required action, to change the location of objects by grasping and posture. Robot is the automated production of a kind used in the process of crawling and mo ving piece features automatic device, which is mechanized and automated production process developed a new type of device. In recent years, as electronic technology, esp ecially computer extensive use of robot development and production of high-tech fiel ds has become a rapidly developed a new technology, which further promoted the dev elopment of robot, allowing robot to better achieved with the combination of mechani zation and automation. Robot can replace humans completed the risk of duplication of boring work, to reduce human labor intensity and improve labor productivity. Manipu lator has been applied more and more widely, in the machinery industry, it can be use d for parts assembly, work piece handling, loading and unloading, particularly in the a utomation of CNC machine tools, modular machine tools more commonly used. At pr esent, the robot has developed into a FMS flexible manufacturing systems and flexibl e manufacturing cell in an important component of the FMC. The machine tool equipment and machinery in hand together constitute a flexible manufacturing system or a f lexible manufacturing cell, it was adapted to small and medium volume production, y ou can save a huge amount of the work piece conveyor device, compact, and adaptabl e. When the work piece changes, flexible production system is very easy to change wi ll help enterprises to continuously update the marketable variety, improve product qua lity, and better adapt to market competition. At present, China's industrial robot techno logy and its engineering application level and comparable to foreign countries there is a certain distance, application and industrialization of the size of the low level of robo t research and development of a direct impact on raising the level of automation in Ch ina, from the economy, technical considerations are very necessary. Therefore, the stu dy of mechanical hand design is very meaningful.附件1:外文资料翻译译文机械手机械手是近几十年发展起来的一种高科技自动化生产设备。

机械手臂应用领域的外文文献以及翻译

机械手臂应用领域的外文文献以及翻译

机械手臂应用领域的外文文献以及翻译1. Introduction机械手臂是一种用于执行各种任务的自动化设备,其应用领域广泛。

本文档提供了一些关于机械手臂应用领域的外文文献,并附有简要的翻译。

2. 文献1: "Advancements in Robotic Arm Control Systems"- Author: John Smith- Published: 2020这篇文献详细介绍了机械手臂控制系统的最新进展。

作者讨论了各种控制算法、传感器和执行器的应用,以提高机械手臂的性能和精确度。

3. 文献2: "Applications of Robotic Arms in Manufacturing Industry"- Author: Emily Chen- Published: 2018作者在这篇文献中研究了机械手臂在制造业中的应用。

她列举了多个实例,包括机械手臂在装配、焊接和搬运等任务中的应用,以及通过使用机械手臂能够提高生产效率和质量的案例。

4. 文献3: "Robot-Assisted Surgery: The Future of Medical Industry"- Author: David Johnson- Published: 2019这篇文献探讨了机械手臂在医疗行业中的应用,特别是机器人辅助外科手术。

作者解释了机械手臂在手术过程中的优势,包括更小的切口、更高的精确度和减少术后恢复时间等方面。

5. 文献4: "Exploring the Potential of Robotic Arms in Agriculture"- Author: Maria Rodriguez- Published: 2021这篇文献研究了机械手臂在农业领域的潜力。

作者探讨了机械手臂在种植、收割和除草等农业任务中的应用,以及如何通过机械化技术改善农业生产的效率和可持续性。

机械工程专业外文文献及翻译

机械工程专业外文文献及翻译

机械工程专业外文文献及翻译文献一(外文标题)
摘要:
该文献研究了机械工程领域中的某个具体问题。

通过实验方法和数学模型的分析,作者得出了一些有意义的结论。

本文介绍了作者的研究方法和结果,并讨论了其在机械工程领域的应用前景。

翻译:
(将文献的主要内容用简洁准确的语言翻译成中文)
文献二(外文标题)
摘要:
该文献探讨了机械工程领域中的另一个重要问题。

通过实证分析和理论推导,作者提出了解决方案,并对其进行了验证。

本文阐述了作者的方法和实验结果,并探讨了其在实践中的应用潜力。

翻译:
(将文献的主要内容用简洁准确的语言翻译成中文)
文献三(外文标题)
摘要:
该文献研究了机械工程领域中的另一个新颖课题。

作者通过数
值模拟和实验验证,得出了一些有趣的发现。

本文介绍了作者的研
究过程和结果,并讨论了其对机械工程领域的影响。

翻译:
(将文献的主要内容用简洁准确的语言翻译成中文)
总结
本文档介绍了三篇机械工程专业的外文文献,包括摘要和翻译。

这些文献都对机械工程领域中的不同问题进行了研究,并提出了相
关的解决方案和发现。

希望这些文献能为机械工程专业的学生和研
究人员提供有价值的参考和启发。

机械手臂外文文献翻译、中英文翻译、外文翻译

机械手臂外文文献翻译、中英文翻译、外文翻译

机械手臂外文文献翻译、中英文翻译、外文翻译外文出处:《Manufacturing Engineering and Technology—Machining》附件1:外文原文XXXRobot XXX decades as high-XXX branch of industrial robots. It features can be programmed to perform tasks in a variety of expectations, in both structure and performance advantages of their own people and machines, in particular, XXX the work in the field of national economy and there are broad prospects for development. With the development of industrial automation, there has been CNC machining center, it is in reducing labor intensity, XXX, the upper and lower common in CNC machining processesmaterial, usually still use XXX relay-controlled semi-automatic device. The former time-consuming and labor intensive, inefficient; XXX, require more relays, XXX, XXX interference, XXX, XXX Programmable Logic Controller PLC-controlled robot control system formaterials up and down movement is simple, circuit design is reasonable, with a strong anti-jamming capability, ensuring the system'XXX, reduced maintenance rate,and XXXmechanics, mechanics, XXX, XXX, XXX and other fields of science, is a cross-disciplinary XXX.First, an overview of industrial manipulatorRobot is a kind of positioning control can be automated and can be re-programmedto change in multi-functional machine, which has multiple degrees of freedom can beused to carry an object in order to XXX China, plastic products industry, although still a labor-intensive, XXX1Europe and the United XXX, XXX-intensive South China, East China's coastal areas, XXX, because they have to face a high turnover rate of workers, as well as for theworkers to pay work-related injuries XXX.With the rapid development of China's industrial production, especially the reformand XXX workpiece handling, steering, XXX brazing, spray gun, wrenches and other tools for processing and assembly operations since, which has more and more attracted our attention. Robot is to imitate the manual part of the action,according toa given program, track and requirements for automatic capture, XXX.In real life, you will find this a problem. In the machine shop, the processing of parts loading time is not annoying, and labor productivity is not high, the cost of production major, and sometimes man-made incidents will occur, resulting in processing wereinjured. Think about what could replace it with the processing time of a tour as long as there are a few people, and can operate 24 hours saturated human right? The answeris yes, but the robot can come to replace it.XXX can increase XXX; XXX, ensuring product quality, to achieve safe production; particularly in the high-temperature, high pressure, low temperature, low pressure, dust, explosive, XXX the normal working people. Here I would like to think of designing a robot tobe used in actual production.XXX power: pneumatic robot refersto the compressed air as power source-driven robot. With pressure-driven and other energy-driven comparison have the following advantages: 1. Air inexhaustible, used XXX, does not require recycling and disposal,do not pollute the XXX. (Concept of environmental protection) 2. Air stick is small, the pi2peline pressure loss is small (typically less than asphalt gas path pressure drop of one-thousandth), to facilitate long-distance transport. 3. Compressed air of the working pressure is low (usually 4 to 8 kg / per square centimeter), and therefore moving the material components and XXX. With the hydraulic transmission, compared to its faster action and reaction, which is one of the advantages pneumatic outstanding. 5. The air cleaner media, it will not degenerate, not easy to plug the pipeline. But there are also places where it fly in the ointment: 1. As the compressibility of air, XXX the work, XXX as the precision of the velocity and not easily controlled. 2. As the use of low atmospheric pressure, the output power can not be too large; in order to increase the output power is bound to the structure of the entire pneumatic system size increased.With pneumatic drive and compare with other energy sources drive has the following advantages:Air inexhaustible, used XXX, without recycling anddisposal, do not pollute the XXX or a small amount of leakage would not be a XXX of air is small, the pipeline pressure loss also is very small, easy long-distance transport.The lower working pressure of compressed air, XXX general, reciprocating thrust in 1 to 2 tons XXX.Compared with the hydraulic transmission, and its faster action and reaction, XXX.Clean air medium, it will not degenerate, not easy to plug the pipeline. It can be safely used in flammable, XXX.Second, XXX, mechanical handRobot in the form of a variety of forms, some relatively simple, some more complicated, but the basic form is the same as the composition of the , Usually by the implementing agencies, transmission systems, control systems and auxiliary devices compose3d.1.Implementing agenciesXXX hands, wrists, arms, pillars. Hands are crawling institutions, is used to clamp and release the workpiece, and similar to human fingers, XXXXXX used to support the arm can also be made mobile as needed.2. TransmissionXXX, hydraulic transmission, XXX.3. Control SystemManipulator control system's main role is to control the robot according to certain procedures, direction, position, speed of action, a simple mechanical hand is generallynot set up a dedicated control system, using only trip switches, relays, control valves and circuits can be achieved dynamic drive system control, so that XXX of action. Action will have to use complex programmable robot controller, the micro-computer control.Three, XXX characteristicsXXX: the first is the general machinerydoes not require manual hand. It is an independent not affiliated with a particular hostdevice. It can be programmed according to the needs of thetask to complete the operation of the provisions. It is XXX, alsohas general machinery, memory, XXX second categoryis the need to manually do it, called the operation of aircraft. It originated in the atom,military industry, first through the operation of machines to complete a particular job,XXX such as the Moon. Used in industrial manipulator also fall into this category. The third category is dedicated manipulator, the XXX auto4matic lines, to solve the machine up and down the XXX known as the "Mechanical Hand", which is the host of services, from the host-driven; exception of a few outside the XXX, XXX.Main features:First, mechanical hand (the upper and lower material robot, assembly robot, handling robot, stacking robot, help robot, vacuum handling machines, vacuum suction crane,labor-saving spreader, pneumatic balancer, etc.).Second, cantilever cranes (cantilever crane, electric chain hoist crane, air balance the hanging, etc.)Third, rail-type transport system (hanging rail, light rail, single girder cranes, double-beam crane)Four, industrial machinery, application of handXXX of the production process developed a new type of device. In recent years, as electronic technology, especially computer extensive use of robot development and production of high-tech fields has XXX, XXX, XXX.Although the robot is not as flexible as staff, but it has to the continuous duplicationof work and labor, I do not know fatigue, not afraid of danger, XXX characteristics when compared with manual large, therefore, mechanical hand has been of great importance to many sectors, and increasingly has been applied widely, forexample:(1) Machining the workpiece loading and unloading, especially in the automatic lathe, combination machine tool use is more common.(2) XXX industry, it can beused to assemble printed circuit boards, XXX industry It can be used to assemble parts and components.(3) The working conditions may be poor, monotonous, repetitive easy to sub-fatigu5XXX.(4) XXX, XXX, XXX..(5) XXX.(6), XXX and testing.Help mechanical hands: also known as the balancer, balance suspended, labor-savingspreader, manual Transfer machine is a kind of weightlessness of manual load system,a novel, time-XXX,belonging to kinds of non-standard design of series products. Customer application needs, XXX of the automatic machinery, it can be a fixed program draws﹑XXX. Application of robot can replace the peopleengaged in monotonous﹑XXX, XXX of production, instead of people in hazardous XXX, XXX personal safety. The late 20th century, 40, the United XXX experiments, the first use of radioactive material handling robot, human robot in a safe room to XXX 50 years later, XXX, for the temperatures, polluted areas, and loading and unloading to take place the work piece material, but also as an auxiliary device in automaticmachine tools, machine tools, automatic production lines and processing center applications, the completion of the upper and lower material, or From the library take place XXX operation. Robot body mainly by the hand and sports XXX with the use of hands and operation of objects of different occasions, often there are clamping﹑XXX﹑﹑XXX﹑XXX, generally 2 to 3 degrees of XXX industry, machinery manufacture, XXX some of the staff and arm motor function, a fixd procedure for the captu6re, handling objects or operating tools, automatic operation device. It can replace human labor in order to achieve the production of heavy XXX the personal safety, which is XXX, metallurgy, electronics, light industry and nuclear power sectors. Mechanical hand tools or other XXX used for additional devices, such as the automatic machines or automatic production line handling and transmission of the workpiece, XXX centers, etc. generally do not have a separate control device. Some operating devices XXX.XXX and sports XXX. Task of hand is holding the workpiece (or tool) components, according to grasping objects by shape, size,weight, material and XXX structural forms, such as clamp type,type and adsorption-based care such as holding. Sports organizations, XXX (swing), XXX the required action, to change the location of objects by grasping and posture.Robot is the automated production of a kind used in the process of crawling and moving piece features automatic device, which is XXX a new type of device. In recent years, as electronic technology, especially computer extensive use of robot development and production of high-tech fields has XXX, XXX, XXX. Robot can replace humans completed the risk of duplication ofboring work, to reduce human XXX widely, in the machinery industry, it can be used for parts assembly, work piece handling, loading and unloadingXXX component of the FMC. The machine tool equip7XXX a flexible manufacturing cell, it was adapted to small and medium volume production, you can save a huge amount of the work piece conveyor device, compact, and adaptable. When the work piece changes, flexible production system is very easy to change will help XXX, improve product quality, and better adapt to market XXX, China'XXX isa certain distance, application andindustrialization of the size of the low level of robot research and development of a direct impact on raising the level of automation in China, from the economy, XXX, the study of mechanical hand design is very meaningful.8附件1:外文资料翻译译文呆板手机械手是近几十年发展起来的一种高科技自动化生产设备。

机械专业毕业设计外文翻译1

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。

机械专业外文翻译中英文翻译外文文献翻译

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,。

挖掘机外文翻译外文文献中英翻译

挖掘机外文翻译外文文献中英翻译

挖掘机外文翻译外文文献中英翻译Excavator Translation: English Translation of Foreign LiteratureAbstract:The translation of foreign literature plays a significant role in acquiring knowledge and broadening horizons. In this article, we will explore the translation of foreign literature related to excavators. By analyzing various examples, we aim to provide an insightful understanding of the translation process and techniques involved in conveying the essence of foreign texts to the target language.1. IntroductionThe field of construction machinery presents numerous challenges when it comes to translation due to the technical nature of the content. Translating related literature helps engineers and professionals gain access to international best practices, safety guidelines, and advancements. One of the key areas within construction machinery is excavators, which serve as the focus of this article's English translation of foreign literature.2. Historical Background and EvolutionBefore delving into translations of foreign literature, it is essential to understand the historical background and evolution of excavators. The first excavators can be traced back to ancient civilizations such as the Egyptians and Greeks. Through detailed research and analysis, these ancient excavation methods have gradually evolved into the sophisticated machinery used today.3. Translation Techniques for Excavator-Related TerminologyTranslating technical terms accurately is crucial in preserving the integrity and clarity of the original text. When it comes to excavators, some terms might not have a direct equivalent in the target language. In such cases, the translator must employ various techniques like borrowing, calque, explanation, or using a closest possible translation. Balancing accuracy and readability is a crucial aspect of this translation process.4. Examples of Translated Excavator LiteratureTo demonstrate the translation techniques mentioned earlier, several examples will be provided in this section. These examples will range from user manuals, safety guidelines, to technical specifications and advancements. Through examining these examples, readers will gain insight into the specific challenges faced during translation and the strategies usedto overcome them.5. Cultural Considerations in Excavator TranslationsIn addition to technical accuracy, cultural considerations play a vital role in translating excavator literature. Different cultures may have varying perceptions and terminologies related to construction machinery. Translators need to be aware of cultural nuances to ensure that the translated materials are not only accurate but also culturally appropriate for the target audience.6. ConclusionIn conclusion, the translation of foreign literature on excavators is of great importance in the field of construction machinery. By accurately conveying the technical details, safety guidelines, and advancements fromforeign texts, engineers and professionals can broaden their knowledge and stay updated with international practices. The translation process involves employing various techniques and considering cultural aspects. As a result, it is crucial for translators to possess both technical expertise and cultural sensitivity when undertaking such translations.Through this article, we have explored the significance of excavator translation, the challenges faced, and the techniques employed. It is the bridge that connects language barriers, facilitates learning, and fosters advancements in the field.。

《机械外文翻译文献翻译液压传动》

《机械外文翻译文献翻译液压传动》

英文原文Hydraulic SystemHydraulic presser drive and air pressure drive hydraulic fluid as the transmission is made according to the 17th century, Pascal's principle of hydrostatic pressure to drive the development of an emerging technology, the United Kingdo m in 1795 • Braman Joseph (Joseph Braman ,1749-1814), in London water as a medium to form hydraulic press used in industry, the birth of the world's first hydraulic press. Media work in 1905 will be replaced by oil-water and further improved.Hydraulic transmission There are many outstanding advantages, it is widely used, such as general industr- ial use of plastics processing machinery, the pressure of machinery, machine tools, etc.; operating machinery engineering machinery, construction machinery, agricultural machinery, automobiles, etc.; iron and steel indu- stry metallurgical machinery, lifting equipment, such as roller adjustment device; civil water projects with flo- od control and dam gate devices, bed lifts installations, bridges and other manipulation of institutions; speed turbine power plant installations, nuclear power plants, etc.; ship from the deck heavy machinery (winch), the bow doors, bulkhead valve, stern thruster, etc.; special antenna technology giant with control devices, measu- rement buoys, movements such as rotating stage; military-industrial control devices used in artillery, ship anti- rolling devices, aircraft simulation, aircraft retractable landing gear and rudder control devices and other devi- ces.A complete hydraulic system consists of five parts, namely, power components, the implementation of co- mponents, control components, auxiliary components and hydraulic oil.The role of dynamic components of the original motive fluid into mechanical energy to the pressure that the hydraulic system of pumps, it is to power the entire hydraulic system. The structure of the form of hydra- ulic pump gears are generally pump, vane pump and piston pump.Implementation of components (such as hydraulic cylinders and hydraulic motors) which is the pressure of the liquid can be converted to mechanical energy to drive the load for a straight line reciprocating movement or rotational movement.Control components (that is, the various hydraulic valves) in the hydraulic system to control and regulate the pressure of liquid, flow rate and direction. According to the different control functions, hydraulic pressure control valve can be divided into valves, flow control valves and directional control valve. Pressure control valves are divided into benefits flow valve (safety valve), pressure relief valve, sequence valve, pressure relays, etc.; flow control valves including throttle, adjusting the valves, flow diversion valve sets, etc.; directional control valve includes a one-way valve , one-way fluid control valve, shuttle valve, valve and so on. Under the control of different ways, can be divided into the hydraulic valve control switch valve, control valve and set the value of the ratio control valve.Auxiliary components, including fuel tanks, oil filters, tubing and pipe joints, seals, pressure gauge, oil level, such as oil dollars.Hydraulic oil in the hydraulic system is the work of the energy transfer medium, there are a variety of mineral oil, emulsion oil hydraulic molding Hop categories.The role of the hydraulic system is to help humanity work. Mainly by the implementation of components to rotate or pressure into a reciprocating motion.Hydraulic system and hydraulic power control signal is composed of two parts, the signal control of some parts of the hydraulic power used to drive the control valve movement.Part of the hydraulic power means that the circuit diagram used to show the different functions of the interrelationship between components. Containing the source of hydraulic pump, hydraulic motor and auxiliary components; hydraulic control part contains a variety of control valves, used to control the flow of oil, pressure and direction; operative or hydraulic cylinder with hydraulic motors, according to the actual requirements of their choice.In the analysis and design of the actual task, the general block diagram shows the actual operation of equi - pment. Hollow arrow indicates the signal flow, while the solid arrows that energy flow.Basic hydraulic circuit of the action sequence - Control components (two four-way valve) and the spring to reset for the implementation of components (double-acting hydraulic cylinder), as well as the extending and retracting the relief valve opened and closed . For the implementation of components and control components, presentations are based on the corresponding circuit diagram symbols, it also introduced ready made circuit diagram symbols.Working principle of the system, you can turn on all circuits to code. If the first implementation of components numbered 0, the control components associated with the identifier is 1. Out with the implementation of components corresponding to the identifier for the even components, then retracting and implementation of components corresponding to the identifier for the odd components. Hydraulic circuit carried out not only to deal with numbers, but also to deal with the actual device ID, in order to detect system failures.DIN ISO1219-2 standard definition of the number of component composition, which includes the following four parts: device ID, circuit ID, component ID and component ID. The entire system if only one device, device number may be omitted.Practice, another way is to code all of the hydraulic system components for numbers at this time, components and component code should be consistent with the list of numbers. This method is particularly applicable to complex hydraulic control system, each control loop are the corresponding number with the systemWith mechanical transmission, electrical transmission compared to the hydraulic drive has the following advantages:1, a variety of hydraulic components, can easily and flexibly to layout.2, light weight, small size, small inertia, fast response.3, to facilitate manipulation of control, enabling a wide range of stepless speed regulation (speed range of 2000:1).4, to achieve overload protection automatically.5, the general use of mineral oil as a working medium, the relative motion can be self-lubricating surface, long service life;6, it is easy to achieve linear motion /7, it is easy to achieve the automation of machines, when the joint control of the use of electro-hydraulic, not only can achieve a higher degree of process automation, and remote control can be achieved.The shortcomings of the hydraulic system:1, as a result of the resistance to fluid flow and leakage of the larger, so less efficient. If not handled properly, leakage is not only contaminated sites, but also may cause fire and explosion.2, vulnerable performance as a result of the impact of temperature change, it would be inappropriate in the high or low temperature conditions.3, the manufacture of precision hydraulic components require a higher, more expensive and hence the price. 4, due to the leakage of liquid medium and the compressibility and can not be strictly the transmission ratio. 5, hydraulic transmission is not easy to find out the reasons for failure; the use and maintenance requirements for a higher level of technology.In the hydraulic system and its system, the sealing device to prevent leakage of the work of media within and outside the dust and the intrusion of foreign bodies. Seals played the role of components, namely seals. Medium will result in leakage of waste, pollution and environmental machinery and even give rise to malfunctioning machinery and equipment for personal accident. Leakage within the hydraulic system will cause a sharp drop in volumetric efficiency, amounting to less than the required pressure, can not even work. Micro-invasive system of dust particles, can cause or exacerbate friction hydraulic component wear, and further lead to leakage.Therefore, seals and sealing device is an important hydraulic equipment components. The reliability of its机械专业中英文文献翻译work and life, is a measure of the hydraulic system an important indicator of good or bad. In addition to the closed space, are the use of seals, so that two adjacent coupling surface of the gap between the need to control the liquid can be sealed following the smallest gap. In the contact seal, pressed into self-seal-style and self-styled self-tight seal (ie, sealed lips) two.The three hydraulic system diseases1, as a result of heat transmission medium (hydraulic oil) in the flow velocity in various parts of the existence of different, resulting in the existence of a liquid within the internal friction of liquids and pipelines at the sam- e time there is friction between the inner wall, which are a result of hydraulic the reasons for the oil tempera- ture. Temperature will lead to increased internal and external leakage, reducing its mechanical efficiency. At the same time as a result of high temperature, hydraulic oil expansion will occur, resulting in increased com- pression, so that action can not be very good control of transmission. Solution: heat is the inherent characte -ristics of the hydraulic system, not only to minimize eradication. Use a good quality hydraulic oil, hydraulic piping arrangement should be avoided as far as possible the emergence of bend, the use of high-quality pipe and fittings, hydraulic valves, etc.2, the vibration of the vibration of the hydraulic system is also one of its malaise. As a result of hydraulic oil in the pipeline flow of high-speed impact and the control valve to open the closure of the impact of the process are the reasons for the vibration system. Strong vibration control action will cause the system to error, the system will also be some of the more sophisticated equipment error, resulting in system failures. Solutions: hydraulic pipe should be fixed to avoid sharp bends. To avoid frequent changes in flow direction, can not avoid damping measures should be doing a good job. The entire hydraulic system should have a good damping measures, while avoiding the external local oscillator on the system.3, the leakage of the hydraulic system leak into inside and outside the leakage leakage. Leakage refers to the process with the leak occurred in the system, such as hydraulic piston-cylinder on both sides of the leakage, the control valve spool and valve body, such as between the leakage. Although no internal leakage of hydra- ulic fluid loss, but due to leakage, the control of the established movements may be affected until the cause system failures. Outside means the occurrence of leakage in the system and the leakage between the external environment. Direct leakage of hydraulic oil into the environment, in addition to the system will affect the working environment, not enough pressure will cause the system to trigger a fault. Leakage into the enviro- nment of the hydraulic oil was also the danger of fire. Solution: the use of better quality seals to improve the machining accuracy of equipment.Another: the hydraulic system for the three diseases, it was summed up: "fever, with a father拉稀" (This is the summary of the northeast people). Hydraulic system for the lifts, excavators, pumping station, dynamic, crane, and so on large-scale industry, construction, factories, enterprises, as well as elevators, lifting platforms, Deng Axle industry and so on.Hydraulic components will be high-performance, high-quality, high reliability, the system sets the direction of development; to the low power, low noise, vibration, without leakage, as well as pollution control, water-based media applications to adapt to environmental requirements, such as the direction of development; the development of highly integrated high power density, intelligence, mechatronics and micro-light mini-hydraulic components; active use of new techniques, new materials and electronics, sensing and other high-tech.Hydraulic coupling to high-speed high-power and integrated development of hydraulic transmission equ- ipment, development of water hydraulic coupling medium speed and the field of automotive applications to develop hydraulic reducer, improve product reliability and working hours MTBF; hydraulic torque converter to the development of high-power products, parts and components to improve the manufacturing process tech -nology to improve reliability, promote computer-aided technology, the development of hydraulic torque con- verter and power shift transmission technology supporting the use of ; Clutch fluid viscosity should increase the quality of products, the formation of bulk to the high-power and high-speed direction.Pneumatic Industry:Products to small size, light weight, low power consumption, integrated portfolio of development, the implementation of the various types of components, compact structure, high positioning accuracy of the direction of development; pneumatic components and electronic technology, to the intelligent direction of development; component performance to high-speed, high-frequency, high-response, high-life, high temp- erature, high voltage direction, commonly used oil-free lubrication, application of new technology, new technology and new materials.(1)used high-pressure hydraulic components and the pressure of continuous work to reach 40Mpa, the maximum pressure to achieve instant 48Mpa;(2) diversification of regulation and control;(3) to further improve the regulation performance, increase the efficiency of the powertrain;(4) development and mechanical, hydraulic, power transmission of the composite portfolio adjustment gear;(5) development of energy saving, energy efficient system function;(6) to further reduce the noise;(7) Application of Hydraulic Cartridge V alves thread technology, compact structure, to reduce the oil spill Water-based hydraulic systemsWater-based hydraulic systems traditionally have been used in hot-metal areas of steel mills. The obvious advantage of water systems in these industries is their fire resistance. Water-based hydraulic systems also have obvious cost advantages over oil-based fluid. First, non-toxic, biodegradable synthetic additives for water cost $5 to $6 per gallon. One gallon of concentrate can make 20 gallons of a 5% solution, so the cost of water-based hydraulic fluid actually can be less than 30 cents per gallon.Considering the costs associated with preventing and cleaning up environmental contamination, water-based hydraulic systems hold the potential for tremendous cost savings at the plant level. Oil that has leaked already becomes a very important problem. It must be collected, properly contained. Water containing synthetic additives, however, can by dumped into plant effluent systems.Cost savings at the plant level don&#39;t stop at the lower cost of the fluid and its disposal. Because water-based hydraulic fluid consists of 10 parts water and one part synthetic additive, 5 gallons of additive mixes with water to make 100 gallons of water-based fluid. A 50gallon container is certainly easier to handle than two 55-gallon drums, so warehousing is simpler, cleaner, and less cluttered. Transportation costs also are lower.Other potential plant-wide savings include improved safety for workers because the water-based fluid is non-toxic as well as non-flammable. These attributes can reduce plant insurance rates. Spills cost less to clean up because granular absorbents or absorbent socks are unnecessary. Water is &quot;hot&quot; againThe oil embargo in the 1970s sparked interest in water-based fluids as a less-costly alternative to oils. Even the most expensive water additives became attractive when designers learned that one gallon of concentrate would make 20 gallons of fluid.As oil prices gradually dropped, so did interest in water-based hydraulics. In retrospect, interest in water-based fluids centered around their cost saving potential. Most designers lost interest when they discovered that they could not just change the fluid in their systems from oil to water without making other substantial changes. They then become reluctant to accept other &quot;disadvantages&quot; - read substantial changes - of switching over to water-based hydraulics.What were viewed as disadvantages were really different rules that apply to water-based hydraulic systems? Designers probably resisted learning more about water-based hydraulics because they were intimated by all the work required to lean about how to design a new system or retrofit an older system. By closing their minds to this different technology, they missed the many other advantages of water-based fluid beyond initial cost. Now that environmental concerns have added disposal costs to the price of hydraulic fluids, water-based hydraulics has again become a hot topic.Fighting freezeWater-based hydraulic systems do, of course, have limits to their applications. One limitation is the potential of freezing. This possibility is probably the most significant blockade to more widespread application of机械专业中英文文献翻译water-based systems, especially in the mobile equipment industry. Longwall mining is by far the largest sector of mobile equipment that has been able to take advantage of water-based systems. Temperatures underground do not approach the freezing point of water, and fire resistance is essential. Mobile and even marine equipment used in temperate climates could cash in one the advantages of water based systems, but there is no guarantee that such equipment always will be used in above-freezing temperatures.Nevertheless, adding an anti-freeze to a water-based fluid can depress its freezing temperature to well below 32°F. Ethylene glycol - used in automotive anti-freeze - is toxic and is not biodegradable, so its use for anti-freeze in water-based hydraulic fluid would defeat the environmental advantage water-based fluid has. There is an alternative. Propylene glycol is not toxic and is biodegradable. It costs more than ethylene glycol and is not quite as effective antifreeze, so it must be used in slightly higher concentrations. Two more techniques to reduce freezing potential are to keep fluid circulating continuously and use hose where practical. Sealing the systemTwo more perceived problems with water hydraulic systems are bacterial infestation and difficulty in maintain proper concentrations. Sealing the system from atmosphere can hold bacterial growth in check. Addition of an anti-bacterial agent to the fluid can have a lasting effect on preventing bacterial buildup if air is excluded from the system.A sealed reservoir eliminates another problem suffered by many hydraulic systems: water ingression. This addresses another misconception about water-based systems: water-based systems not sealed from the atmosphere must be closely monitored to ensure that the additive concentration stays within tolerance. That is because water evaporates from the reservoir more readily than the additive does. Consequently, water evaporation causes the additive concentration to increase. When new fluid is added to a system, samples of the existing fluid must be taken to determine the concentration of additive in solution. These results then reveal the ratio of additive to fluid that must be added so that fluid concentration is correct.With a system that seals fluid from the atmosphere, the evaporation problem is virtually eliminated. Fluid that escapes by leakage is a solution containing water and additive. Therefore, the quantity of fluid in the system changes, but concentration does not. System fluid is replen ished simply by adding a pre-mixed solution of water and additive to the reservoir.中文原文液压传动液压传动和气压传动称为流体传动,是根据17世纪帕斯卡提出的液体静压力传动原理而发展起来的一门新兴技术,1795年英国约瑟夫•布拉曼(Joseph Braman,1749-1814),在伦敦用水作为工作介质,以水压机的形式将其应用于工业上,诞生了世界上第一台水压机。

农业用机械设备外文文献翻译、中英文翻译、外文翻译

农业用机械设备外文文献翻译、中英文翻译、外文翻译

农业用机械设备外文文献翻译、中英文翻译、外文翻译在公元前1世纪,中国已经开始推广使用耧,这是世界上最早的条播机具,在北方旱作区仍然得到应用。

1636年,希腊制造了世界上第一台播种机。

1830年,俄国人在畜力多铧犁上加装播种装置制成了犁播机。

1860年后,英美等国开始大量生产畜力谷物条播机。

20世纪后,牵引和悬挂式谷物条播机以及运用气力排种的播种机相继出现。

50年代,精密播种机开始得到发展。

中国从20世纪50年代开始引进谷物条播机、棉花播种机等。

60年代,中国先后研制成了悬挂式谷物播种机、离心式播种机、通用机架播种机和气吸式播种机等多种类型,并研制成了磨纹式排种器。

到70年代,中国已经形成了播种中耕通用机和谷物联合播种机两个系列,并成功研制出了精密播种机。

播种机具有播种均匀、深浅一致、行距稳定、覆土良好、节省种子、工作效率高等特点。

正确使用播种机应注意以下10个要点:1)在进田作业前,要清理播种箱内的杂物和开沟器上的缠草、泥土,确保状态良好。

对拖拉机及播种机的各传动、转动部位,按照说明书的要求加注润滑油,尤其是每次作业前要注意传动链条润滑和张紧情况以及播种机上螺栓的紧固情况。

2)机架不能倾斜,播种机与拖拉机挂接后,不得倾斜,工作时应使机架前后呈水平状态。

3)搞好各种调整,按照使用说明书的规定和农艺要求,将播种量、开沟器的行距、开沟覆土镇压轮的深浅调整适当。

Seeder Tips1.Pay n to adding good quality seeds to the seed box to XXX。

Make sure there are no small。

broken。

or impure seeds。

Also。

XXX.2.Before large-scale seeding。

conduct a 20-XXX.3.Choose a suitable route for the seeding machine to move ina straight line at a constant speed。

机械专业外文文献翻译--对振动侦查和测量的一种实用方法

机械专业外文文献翻译--对振动侦查和测量的一种实用方法

英文原文A Practical Approach to Vibration Detection and Measurement——Physical Principles and Detection TechniquesBy: John Wilson, the Dynamic Consultant, LLCThis tutorial addresses the physics of vibration; dynamics of a spring mass system; damping; displacement, velocity, and acceleration; and the operating principles of the sensors that detect and measure these properties. Vibration is oscillatory motion resulting from the application of oscillatory or varying forces to a structure. Oscillatory motion reverses direction. As we shall see, the oscillation may be continuous during some time period of interest or it may be intermittent. It may be periodic or nonperiodic, i.e., it may or may not exhibit a regular period of repetition. The nature of the oscillation depends on the nature of the force driving it and on the structure being driven.Motion is a vector quantity, exhibiting a direction as well as a magnitude. The direction of vibration is usually described in terms of some arbitrary coordinate system (typically Cartesian or orthogonal) whose directions are called axes. The origin for the orthogonal coordinate system of axes is arbitrarily defined at some convenient location.Most vibratory responses of structures can be modeled as single-degree-of-freedom spring mass systems, and many vibration sensors use a spring mass system as the mechanical part of their transduction mechanism. In addition to physical dimensions, a spring mass system can be characterized by the stiffness of the spring, K, and the mass, M, or weight, W, of the mass. These characteristics determine not only the static behavior (static deflection, d) of the structure, but also its dynamic characteristics. If g is the acceleration of gravity:F = MAW = MgK = F/d = W/dd = F/K = W/K = Mg/KDynamics of a Spring Mass SystemThe dynamics of a spring mass system can be expressed by the system's behavior in free vibration and/or in forced vibration.Free Vibration. Free vibration is the case where the spring is deflected and then released and allowed to vibrate freely. Examples include a diving board, a bungee jumper, and a pendulum or swing deflected and left to freely oscillate.Two characteristic behaviors should be noted. First, damping in the system causes the amplitude of the oscillations to decrease over time. The greater the damping, the faster the amplitude decreases. Second, thefrequency or period of the oscillation is independent of the magnitude of the original deflection (as long as elastic limits are not exceeded). The naturally occurring frequency of the free oscillations is called the natural frequency, f n:(1)Forced Vibration. Forced vibration is the case when energy is continuously added to the spring mass system by applying oscillatory force at some forcing frequency, f f. Two examples are continuously pushing a child on a swing and an unbalanced rotating machine element. If enough energy to overcome the damping is applid, the motion will continue as long as the excitation continues. Forced vibration may take the form of self-excited or externally excited vibration. Self-excited vibration occurs when the excitation force is generated in or on the suspended mass; externally excited vibration occurs when the excitation force is applied to the spring. This is the case, for example, when the foundation to which the spring is attached is moving.Transmissibility. When the foundation is oscillating, and force is transmitted through the spring to the suspended mass, the motion of the mass will be different from the motion of the foundation. We will call the motion of the foundation the input, I, and the motion of the mass the response, R. The ratio R/I is defined as the transmissibility, Tr:Tr = R/IResonance. At forcing frequencies well below the system's natural frequency, R I, and Tr 1. As the forcing frequency approaches the natural frequency, transmissibility increases due to resonance. Resonance is the storage of energy in the mechanical system. At forcing frequencies near the natural frequency, energy is stored and builds up, resulting in increasing response amplitude. Damping also increases with increasing response amplitude, however, and eventually the energy absorbed by damping, per cycle, equals the energy added by the exciting force, and equilibrium is reached. We find the peak transmissibility occurring when f f f n. This condition is called resonance.Isolation. If the forcing frequency is increased above f n, R decreases. When f f = 1.414 fn, R = I and Tr = 1; at higher frequencies R <I and Tr <1. At frequencies when R <I, the system is said to be in isolation. That is, someof the vibratory motion input is isolated from the suspended mass.Effects of Mass and Stiffness Variations. From Equation (1) it can be seen that natural frequency is proportional to the square root of stiffness, K, and inversely proportional to the square root of weight, W, or mass, M. Therefore, increasing the stiffness of the spring or decreasing the weight of the mass increases natural frequency.DampingDamping is any effect that removes kinetic and/or potential energy from the spring mass system. It is usually theresult of viscous (fluid) or frictional effects. All materials and structures have some degree of internal damping. In addition, movement through air, water, or other fluids absorbs energy and converts it to heat. Internal intermolecular or intercrystalline friction also converts material strain to heat. And, of course, external friction provides damping.Damping causes the amplitude of free vibration to decrease over time, and also limits the peak transmissibility in forced vibration. It is normally characterized by the Greek letter zeta () , or by the ratio C/C c, where c is the amount of damping in the structure or material and C c is "critical damping." Mathematically, critical damping is expressed as C c = 2(KM)1/2. Conceptually, critical damping is that amount of damping which allows the deflected spring mass system to just return to its equilibrium position with no overshoot and no oscillation. An underdamped system will overshoot and oscillate when deflected and released. An overdamped system will never return to its equilibrium position; it approaches equilibrium asymptotically. Displacement, Velocity, and AccelerationSince vibration is defined as oscillatory motion, it involves a change of position, or displacement (see Figure 1).Figure 1.Phase relationships among displacement, velocity, and acceleration are shown on these time history plots.Velocity is defined as the time rate of change of displacement; acceleration is the time rate of change of velocity. Some technical disciplines use the term jerk to denote the time rate of change of acceleration.Sinusoidal Motion Equation. The single-degree-of-freedom spring mass system, in forced vibration, maintained at a constant displacement amplitude, exhibits simple harmonic motion, or sinusoidal motion. That is, its displacement amplitude vs. time traces out a sinusoidal curve. Given a peak displacement of X, frequency f, and instantaneous displacement x:(2)at any time, t.Velocity Equation. Velocity is the time rate of change of displacement, which is the derivative of the time function of displacement. For instantaneous velocity, v:(3)Since vibratory displacement is most often measured in terms of peak-to-peak, double amplitude, displacement D = 2X:(4)If we limit our interest to the peak amplitudes and ignore the time variation and phase relationships:(5)where:V = peak velocityAcceleration Equation. Similarly, acceleration is the time rate of change of velocity, the derivative of the velocity expression:(6)and(7)where:A = peak accelerationIt thus can be shown that:V = fDA = 22 f2 DD = V/ fD = A/22 f2From these equations, it can be seen that low-frequency motion is likely to exhibit low-amplitude accelerations even though displacement may be large. It can also be seen that high-frequency motion is likely to exhibit low-amplitude displacements, even though acceleration is large. Consider two examples:• At 1 Hz, 1 in. pk-pk displacement is only ~0.05 g acceleration; 10 in. is ~0.5 g • At 1000 Hz, 1g acceleration is only ~0.00002 in. displacement; 100 g is ~0.002 in.Measuring Vibratory DisplacementOptical Techniques. If displacement is large enough, as at low frequencies, it can be measured with a scale, calipers, or a measuring microscope. At higher frequencies, displacement measurement requires more sophisticated optical techniques.High-speed movies and video can often be used to measure displacements and are especially valuable for visualizing the motion of complex structures and mechanisms. The two methods are limited by resolution to fairly large displacements and low frequencies. Strobe lights and stroboscopic photography are also useful when displacements are large enough, usually >0.1 in., to make them practical.The change in intensity or angle of a light beam directed onto a reflective surface can be used as an indication of its distance from the source. If the detection apparatus is fast enough, changes of distance can be detected as well.The most sensitive, accurate, and precise optical device for measuring distance or displacement is the laser interferometer. With this apparatus, a reflected laser beam is mixed with the original incident beam. The interference patterns formed by the phase differences can measure displacement down to <100 nm. NIST and other national primary calibration agencies use laser interferometers for primary calibration of vibration measurement instruments at frequencies up to 25 kHz.Electromagnetic and Capacitive Sensors. Another important class of noncontact, special-purpose displacement sensors is the general category of proximity sensors. These are probes that are typically built into machinery to detect the motion of shafts inside journal bearings or the relative motion of other machine elements. The sensors measure relative distance or proximity as a function of either electromagnetic or capacitive (electrostatic) coupling between the probe and the target. Because these devices rely on inductive or capacitive effects, they require an electrically conductive target. In most cases, they must be calibrated for a specific target and specific material characteristics in the gap between probe and target.Electromagnetic proximity sensors are often called eddy current probes because one of the most popular types uses eddy currents generated in the target as its measurement mechanism. More accurately, this type of sensor uses the energy dissipated by the eddy currents. The greater the distance from probe to target, the less electromagnetic coupling, the lower the magnitude of the eddy currents, and the less energy they drain from theprobe. Other electromagnetic probes sense the distortion of an electromagnetic field generated by the probe and use that measurement to indicate the distance from probe to target.Capacitive proximity sensor systems measure the capacitance between the probe and the target and are calibrated to convert the capacitance to distance. Capacitance is affected by the dielectric properties of the material in the gap as well as by distance, so calibration can be affected by a change of lubricant or contamination of the lubricant in a machine environment.Contact Techniques. A variety of relative motion sensors use direct contact with two objects to measure relative motion or distance between them. These include LVDTs, cable position transducers (stringpots), and linear potentiometers. All of these devices depend on mechanical linkages and electromechanical transducers.Seismic Displacement Transducers. These devices, discussed in detail later, were once popular but now are seldom used. They tend to be large, heavy, and short lived.Double Integration of Acceleration. With the increasing availability and decreasing cost of digital signal processing, more applications are using the more rugged and more versatile accelerometers as sensors, then double integrating the acceleration signal to derive displacements. While older analog integration techniques tended to be noisy and inaccurate, digital processing can provide quite high-quality, high-accuracy results.Measuring Vibratory VelocityTransducers. Some of the earliest "high-frequency" vibration measurements were made with electrodynamic velocity sensors. These are a type of seismic transducer that incorporates a magnet supported on a soft spring suspension system to form the seismic (spring mass) system. The magnetic member is suspended in a housing that contains one or more multiturn coils of wire. When the housing is vibrated at frequencies well above the natural frequency of the spring mass system, the mass (magnet) is isolated from the housing vibration. Thus, the magnet is essentially stationary and the housing, with the coils, moves past it at the velocity of the structure to which it is attached. Electrical output is generated proportional to the velocity of the coil moving through the magnetic field. Velocity transducers are used from ~10 Hz up to a few hundred Hz. They tend to be large and heavy, and eventually wear and produce erratic outputs.Laser Vibrometers. Laser vibrometers or laser velocimeters are relatively new instruments capable of providing high sensitivity and accuracy. They use a frequency-modulated (typically around 44 MHz) laser beam reflected from a vibrating surface. The reflected beam is compared with the original beam and the Doppler frequency shift is used to calculate the velocity of the vibrating surface. Alignment and standoff distance are critical. Because of the geometric constraints on location, alignment, and distances, they are limited to laboratory applications. One version of laser vibrometer scans the laser beam across a field of vision, measuring velocity at each point. The composite can then be displayed as a contour map or a colorized display. The vibration map can be superimposed on a video image to provide the maximum amount of information about velocity variations on a large surface.Integration of Acceleration. As with displacement measurements, low-cost digital signal processing makes it practical to use rugged, reliable, versatile accelerometers as sensors and integrate their output to derive a velocity signal.Measuring Vibratory AccelerationMost modern vibration measurements are made by measuring acceleration. If velocity or displacement data are required, the acceleration data can be integrated (velocity) or double integrated (displacement). Some accelerometer signal conditioners have built-in integrators for that purpose. Accelerometers (acceleration sensors, pickups, or transducers) are available in a wide variety of sizes, shapes, performance characteristics, and prices. The five basic transducer types are servo force balance; crystal-type or piezoelectric; piezoresistive or silicon strain gauge type; integral electronics piezoelectric; and variable capacitance. Despite the different electromechanical transduction mechanisms, all use a variation of the spring mass system, and are classified as seismic transducers.Seismic Accelerometer Principle. All seismic accelerometers use some variation of a seismic or proof mass suspended by a spring structure in a case (see Figure 3). When the case is accelerated, the proof mass is also accelerated by the force transmitted through the spring structure. Then the displacement of the spring, the displacement of the mass within the case, or the forcetransmitted by the spring is transduced into an electrical signal proportional to acceleration.Accelerometers. Transducers designed to measure vibratory acceleration are called accelerometers. There are many varieties including strain gauge, servo force balance, piezoresistive (silicon strain gauge), piezoelectric (crystal-type), variable capacitance, and integral electronic piezoelectric. Each basic type has many variations and trade names. Most manufacturers provide excellent applications engineering assistance to help the user choose the best type for the application, but because most of these sources sell only one or two types, they tend to bias their assistance accordingly.For most applications, my personal bias is toward piezoelectric accelerometers with internal electronics. The primary limitation of these devices is temperature range. Although they exhibit low-frequency roll-off, they are available with extremely low-frequency capabilities. They provide a preamplified low-impedance output, simple cabling, and simple signal conditioning, and generally have the lowest overall system cost.Most important to the user are the performance and environmental specifications and the price. What's inside the box is irrelevant if the instrument meets the requirements of the application, but when adding to existing instrumentation it is important to be sure that the accelerometer is compatible with the signal conditioning. Each type of accelerometer requires a different type of signal conditioning.Accelerometer Types. The most common seismic transducers for shock and vibration measurements are:∙Piezoelectric (PE); high-impedance output∙Integral electronics piezoelectric (IEPE); low-impedance output∙Piezoresistive (PR); silicon strain gauge sensor∙Variable capacitance (VC); low-level, low-frequency∙Servo force balancePiezoelectric (PE) sensors use the piezoelectric effects of the sensing element(s) to produce a charge output. Because a PE sensor does not require an external power source for operation, it is considered self-generating. The "spring" sensing elements provide a given number of electrons proportional to the amount of applied stress (piezein is a Greek word meaning to squeeze). Many natural and man-made materials, mostly crystals or ceramics and a few polymers, display this characteristic. These materials have a regular crystalline molecular structure, with a net charge distribution that changes when strained.Piezoelectric materials may also have a dipole (which is the net separation of positive and negative charge along a particular crystal direction) when unstressed. In these materials, fields can be generated by deformation from stress or temperature, causing piezoelectric or pyroelectric output, respectively. The pyroelectric outputs can be very large unwanted signals, generally occurring over the long time periods associated with most temperature changes. Polymer PE materials have such high pyroelectric output that they were originally used as thermal detectors. There are three pyroelectric effects, which will be discussed later in detail.Charges are actually not "generated," but rather just displaced. (Like energy and momentum, charge is always conserved.) When an electric field is generated along the direction of the dipole, metallic electrodes on faces at the opposite extremes of the gradient produce mobile electrons that move from one face, through the signal conditioning, to the other side of the sensor to cancel the generated field. The quantity of electrons depends on the voltage created and the capacitance between the electrodes. A common unit of charge from a PE accelerometer is the picocoulomb, or 10-12 coulomb, which is something over 6 × 106 electrons.Choosing among the many types of PE materials entails a tradeoff among charge sensitivity, dielectric coefficient (which, with geometry, determines the capacitance), thermal coefficients, maximum temperature, frequency characteristics, and stability. The best S/N ratios generally come from the highest piezoelectric coefficients.Naturally occurring piezoelectric crystals such as tourmaline or quartz generally have low-charge sensitivity, about one-hundredth that of the more commonly used ferroelectric materials. (But these low-charge output materials are typically used in the voltage mode, which will be discussed later.) Allowing smaller size for a given sensitivity, ferroelectric materials are usually man-made ceramics in which the crystalline domains (i.e., regions in which dipoles are naturally aligned) are themselves aligned by a process of artificial polarization.Polarization usually occurs at temperatures considerably higher than operating temperatures to speed the process of alignment of the domains. Depolarization, or relaxation, can occur at lower temperatures, but at very much lower rates, and can also occur with applied voltages and preload pressures. Depolarization always results intemporary or permanent loss of sensitivity. Tourmaline, a natural crystal that does not undergo depolarization, is particularly useful at very high temperatures.Because they are self-generating, PE transducers cannot be used to measure steady-state accelerations or force, which would put a fixed amount of energy into the crystal (a one-way squeeze) and therefore a fixed number of electrons at the electrodes. Conventional voltage measurement would bleed electrons away, as does the sensor's internal resistance. (High temperature or humidity in the transducer would exacerbate the problem by reducing the resistance value.) Energy would be drained and the output would decay, despite the constant input acceleration/force.External measurement of PE transducer voltage output requires special attention to the cable's dynamic behavior as well as the input characteristics of the preamplifier. Since cable capacitance directly affects the signal amplitude, excessive movement of the cable during measurement can cause changes in its capacitance and should be avoided. Close attention should also be paid to the preamp's input impedance; this should be on the order of 1000 M or higher to ensure sufficient low-frequency response.In practice, a charge amplifier is normally used with a PE transducer.Instead of measuring voltage externally, a charge should be measured with a charge converter. It is ahigh-impedance op amp with a capacitor as its feedback. Its output is proportional to the charge at the input and the feedback capacitor, and is nearly unaffected by the input capacitance of the transducer or attached cables. The high-pass corner frequency is set by the feedback capacitor and resistor in a charge converter, and not the transducer characteristics. (The transducer resistance changes noise characteristics, not the frequency.) If time constants are long enough, the AC-coupled transducer will suffice for most vibration measurements.Perhaps the most important limitation of high-impedance output PE transducers is that they must be used with "noise-treated" cables; otherwise, motion in the cable can displace triboelectric charge, which adds to the charge measured by the charge converter. Triboelectric noise is a common source of error found in typical coaxial cables.Most PE transducers are extremely rugged. Each of the various shapes and sizes available comes with its own performance compromises. The most common types of this transducer are compression and shear designs. Shear design offers better isolation from environmental effects such as thermal transient and base strain, and is generally more expensive. Beam-type design, a variation of the compression design, is also quite popular due to its lower manufacturing cost. But beam design is generally more fragile and has limited bandwidth.Integral Electronics Piezoelectric (IEPE). Many piezoelectric accelerometers/force transducers include integral miniature hybrid amplifiers, which, among their other advantages, do not need noise-treated cable. Most require an external constant current power source. Both the input supply current and output signal are carried over the same two-wire cable. The low-impedance output of the IEPE design (see Figure 5) provides relative immunityto the effects of poor cable insulation resistance, triboelectric noise, and stray signal pickup.Output-to-weight ratio of IEPE is higher than with PE transducers. Additional functions can be incorporated into the electronics (see Figure 6), including filters, overload protection, and self-identification.Lower cost cable and conditioning can be used since the conditioning requirements are comparatively lax compared to PE or PR. The sensitivity of IEPE accelerometers/force transducers, in contrast to PR, is not significantly affected by supply changes. Instead, dynamic range, the total possible swing of the output voltage, is affected by bias and compliance voltages. Only with large variations in current supply would there be problems with frequency response when driving high-capacitance loads.A disadvantage of built-in electronics is that it generally limits the transducer to a narrower temperature range. In comparison with an identical transducer design that does not have internal electronics, thehigh-impedance version will always have a higher mean time between failures (MTBF) rating. In addition, the necessarily small size of the amplifier may preclude some of the desirable features offered by a full-blown laboratory amplifier, such as the ability to drive long cable. Slew limiting is therefore a concern with these transducers (some designs have relatively high output impedance) when driving long lines or other capacitive loads. The problem can be remedied by increasing the amount of drive current within the limit specified by the manufacturer.The circuits need not necessarily be charge converters because the capacitance due to leads between the sensor and the amplifier is small and well controlled. Quartz is used in the voltage mode, i.e., with source followers, because its small dielectric coefficient provides comparatively high voltage per unit charge. Voltage conversion also aids ferroelectric ceramics that have the sag in frequency response in charge mode due to their frequency-dependent dielectric coefficient. The amplitude frequency response in the voltage mode is quite flat.Piezoresistive. A PR accelerometer is a Wheatstone bridge of resistors incorporating one or more legs that change value when strained. Because the sensors are externally supplied with energy, the output can be meaningfully DC coupled to respond to steady-state conditions. Data on steady-state accelerations comes at a cost, however. The sensitivity of a bridge varies almost directly with the input excitation voltage, requiring a highly stable and quiet excitation supply .The output of a bridge configuration is the difference between the two output leads. A differential amplifier is required or, alternatively, both leads from the excitation must float to allow one of the output lines to be tied to ground. The differential configuration provides the advantage of common-mode rejection; that is to say, any noise signals picked up on the output lines, if equal, will be canceled by the subtraction in the amplifier.A cautionary note is in order here: With high-output PR transducers, there is a temptation to dispense with an amplifier and simply to connect the output leads directly to an oscilloscope. This will not work if both the scope and the excitation are single ended. Oscilloscopes often have single-ended input (the negative side of the input is ground). If the excitation is also grounded (with the excitation equal to ground), one leg of the bridge is shuntedand the entire excitation voltage is placed across that one leg of the bridge. If you are using AC coupling on the scope, you might misinterpret the reasonably shaped, but small and noisy, output.Most PR sensors use two or four active elements. Voltage output of a two-arm, or half-bridge, sensor is half that of a four-arm, or full bridge.Stability requirements for a PR transducer power supply and its conditioning are considerably tighter than they are for IEPE. Low-impedance PR transducers share the advantages of noise immunity provided by IEPE, although the output impedance of PR is often large enough that it cannot drive large capacitive loads. As is the case with an underdriven IEPE, the result is a low-pass filter on the output, limiting high-frequency response.The sensitivity of a strain gauge comes from both the elastic response of its structure and the resistivity of the material. Wire and thick or thin film resistors have low gauge factors; that is, the ratio of resistance change to the strain is small. Their response is dominated by the elastic response. They are effectively homogeneous blocks of material with resistivity of nearly constant value. As with any resistor, they have a value proportional to length and inversely proportional to cross-sectional area. If a conventional material is stretched, its width reduces while the length increases. Both effects increase resistance.The Poisson ratio defines the amount a lateral dimension is narrowed compared to the amount the longitudinal dimension is stretched. Given a Poisson ratio of 0.3 (a common value), the gauge factor would be 1.6; resistance would change 1.6 × more than it is strained. A typical gauge factor for metal strain gauges is ~2.The response of strain gauges with higher gauge factors is dominated by the piezoresistive effect, which is the change of resistivity with strain. Semiconductor materials exhibit this effect, which, like piezoelectricity, is strongly a function of crystal orientation. Like other semiconductor properties, it is also a strong function of dopant concentration and temperature. Gauge factors near 100 are common for silicon gauges, and, when combined with small size and the stress-concentrating geometries of anisotropically etched silicon, the efficiency of the silicon PR transducer is very impressive. The miniaturization allows natural frequencies >1 MHz in some PR shock accelerometers.Most contemporary PR sensors are manufactured from a single piece of silicon. In general, the advantages of sculpting the whole sensor from one homogeneous block of material are better stability, less thermal mismatch between parts, and higher reliability. Underdamped PR accelerometers tend to be less rugged than PE devices. Single-crystal silicon can have extraordinary yield strength, particularly with high strain rates, but it is a brittle material nonetheless. Internal friction in silicon is very low, so resonance amplification can be higher than for PE transducers. Both these features contribute to its comparative fragility, although if properly designed and installed they are used with regularity to measure shocks well above 100,000 g. They generally have wider bandwidths than PE transducers (comparing models of similar full-scale range), as well as smaller nonlinearities, zero shifting, and hysteresis characteristics. Because they have DC response, they are used when long-duration measurements are to be made.。

机械外文翻译文献翻译影响工件表面质量的因素

机械外文翻译文献翻译影响工件表面质量的因素

英文原文Influence factors on the quality of the workplace surface Processing process on the surface quality of the influenceThe vibration of the process system of the influence on the quality of the surface In mechanical processing process technology system sometimes occur vibration, that is, in the cutting edge tool and workplace is cutting surface except on the name between cutting motion, but also can appear a cyclical relative motion.Vibration that process system by forming movement of the interference and damage, make processing surface appear chatter marks, increases the surface roughness value, worsening processing surface quality.Cutter geometrical parameters, materials and cutting quality to the surface quality of the influence The cutting tool geometric parameters on the surface roughness of the biggest influence is vice PianJiao, the main point PianJiao, arc radius. Under certain conditions, reduce PianJiao, Lord, vice PianJiao point arc radius can reduce surface roughness. Under the same conditions, carbide cutting tools process of surface roughness value less than high speed steel paper cutting knife, and diamond and CBN) tools and better than hard alloy, but because the diamond and iron family affinity materials, it should not be used for processing iron family materials. In addition, the cutting tool before and after the face, cutting knife blade itself directly influence the roughness of the processing the roughness of the surface, therefore, improve the quality of cutting tool, cutting tool and face, cutting knife blade roughness value should be lower than the roughness of the 1 ~ 2 levels.Cutting fluid to the influence on the quality of the surfaceCutting fluid cooling and lubrication effect can reduce the cutting process of interface friction, reduce the temperature of cutting zone, the cutting metal surface layer of plastic deformation degree down, restrain the develop the thorn and scales produced in the production of different materials for reasonable choice of cutting fluids can reduce the surface roughness.The workplace material on the surface quality of the influenceThe workplace material nature; Processing plastic materials, the cutting tools for metal extrusion produced plastic deformation, and the cutting tool and workplace forced separation of the torn scraps effect, make the surface roughness value increase. The workplace material tenacity the better, metal, plastic deformation, the bigger the processing surface is the more the rough. Processing brittle material in the chip broken granular, due to the collapse in broken and endows the machined surface left many pitted surface roughness.General toughness large plastic materials, processing after large surface roughness, and toughness of smaller plastic materials, processing to get smaller after the surface roughness. For the same kind of material, the greater the grain size of the organization, the larger the surface roughness. Therefore, in order to reduce the surface roughness, often in cutting processing of material before quenching and tempering or is the fire of treatment to obtain homogeneous fine grain organization and high hardness.Cutting condition the influence on the quality of the surfaceAnd cutting condition of the relevant process factors, including cutting dosages, cooling lubrication. In low speed processing plastic materials,, easy to produce the develop and scales thorn, so, improve the cutting speed, can reduce the develop and scales thorn, decreasing part already the surface roughness value; For brittle material, general won't form the develop and scales thorn, so, cutting speed on the surface roughness basically no influence. The increase speed, plastic deformation also increases, the surface roughness increases, so, reduce the speed can reduce the surface roughness value, however, feeding reduced to certain value, roughness won't obviously decreased. Normal cutting conditions, cutting depth on the surface roughness the impact is not big, therefore, mechanical process cannot select the too small cutting depth.Cutting speed on the surface roughness influenceGeneral at the early choose low speed cutting and finishing choose high speed cutting can reduce the surface roughness. In the medium speed cutting plastic materials, due to easy to produce the develop, and plastic deformation is bigger, so after processing parts surface roughness is bigger. Usually by low or high speed cutting plastic material, can effectively avoid the develop of generation, this to reduce table and roughness have positive role.On the surface quality of the grinding effectsThe influence of the grinding wheel grinding wheel granularity the thinner, per unit area grain number grinding, the more of the grinding surface in fine scratches the surface roughness is small; But if too fine granularity, processing to jam wheel it will increase the surface roughness, also easy to produce the ripple and cause burns. The hardness of the grinding wheel should be the right size, its half the longer the better passivation period; The hardness of the grinding wheel is too high, grinding mill is not easy to fall off when grain, make processing surface is of friction, extrusion action intensifies, thus increasing the plastic deformation, making the surface roughness increases, also easy cause burns; But the grinding wheel is too soft, grits too easy to fall off, can make grinding action is reduced, leading to the surface roughness increases, so to select the right grinding wheel hardness. Grinding wheel dressing the higher the quality, the surface of the grinding wheel cutting the blade, cutting the number of all the more the better of the blade contour sex, grinding surface roughness and smaller.The influence of the grinding wheel speed increase dosage, unit time through the processing of grinding surface grain number increase, each star grits is ground to reduce thickness of the metal, the surface area of the residual reduced; And at the same time, improve the grinding wheel speed can also reduce the workplace material of plastic deformation, these can make processing surface roughness value reduced. Reduce the speed, unit time through the processing of grinding surface grain number increase, the surface roughness decreased; But the low speed, workplace and grinding wheel contact time long, to the quantity of heat of the increasing, opposite will increase the roughness, may also increase surface burn. Increase grinding depth and longitudinal feeding, the plastic deformation increase, will lead to the surface roughness value increase. Radial feeding increase, the grinding process grinding force and grinding temperature will increase, grinding surface plastic deformation degree increase, which will increase the surface roughness. Toguarantee the machining quality in the premise of grinding efficiency increase, will require a higher surface the coarse grinding and fine grinding separately, coarse grinding is used when the big radial direction feeding, fine grinding the radial feeding the smaller when, finally without into to grinding, to get the surface roughness of surface is very small.The workplace material the workplace material of hardness, plastic and thermal conductivity on the surface roughness of big effect. Large plastic soft material easy jam grinding wheel, thermal conductivity poor heat resistant alloy easy for the abrasive early caving, will lead to increased grinding surface roughness.In addition, because grinding to the high temperature, reasonable use cutting fluids can reduce the grinding of temperature, reduce burns, can also rushed to fall off the grits and scraps, avoid scratch workplace, so as to reduce the surface roughness.Affect the surface of physical and mechanical properties of factorsSurface layer cold hardening. The cutting edges obtuse radius increased, and the surface of metal the extrusion of enhanced, plastic deformation intensifies, cold hard to strengthen. After cutting tool knife surface wear increases, the knife surface and after processed surface friction intensified, plastic deformation increase, cold hard to strengthen. Cutting speed increase, cutting tool and workplace role time is shortened, make plastic deformation expand the depth decreases, and cold hard layer depth decreases. After cutting speed increase, heat cutting in the surface layer effect time also shortened, will make cold hard degree increase. Feeding increases, cutting force also increased, and the surface of the metal plastic deformation intensifies, cold hard effect is strengthening. The workplace material of plastic is larger and the cold hard phenomenon the serious.Surface layer material metallographic composition change. When cutting the heat was processing surface temperature of phase change after more than temperature, the surface of the metal microstructure will change. Grinding burns when a surface temperature of phase change to millers temperature above, metal surface microstructure occurred change, make the surface of the metal strength and hardness of the lower, and with residual stress produce appear even microscopic cracks, this phenomenon is called grinding burns. Improve grinding burns grinding heat caused by grinding way is the root of the burn, so improving grinding burns by two ways: one is as far as possible to reduce the generation of grinding heat; 2 it is improved cooling condition, make as far as possible the quantity of heat to produce less workplace. The correct choice grinding wheel reasonable choice of cutting dosages improved cooling conditions.Surface layer residual stress. Produce residual stress of reason: cutting in processing the metal layer and the surface when there were plastic deformation occurs, the surface of the metal to hematocrit increase; Cutting processing, cutting area will have a lot of heat cutting produce; Different analysis of metallographic organization has different density, also have different olume is necessarily affected by the change of connected the matrix of the metal bar, hence residual stress produce. The main work surface eventually process to the choice of methods. Choose the main parts work surface eventually process method, we must consider the main parts of the specific work surface working conditions and the possible damage to the form. In alternating load,the machine parts on the surface of the local micro cracks, because of tensile stress of action to make primary crack expanding, resulting in parts fracture. Improve parts from the view point of fatigue damage resistance, the final process should choose the surface in the surface produces residual stress processing method. In the machining process, tools on the squash and friction make metal materials happen plastic deformation, cause the original residue area of distortion or groove lines deepened, increases the surface roughness. When the medium or medium low cutting speed cutting plastic material, the surface before the sword in easy to form a high hardness of the devolop, it can take the place of the cutting tool, but state very unstable, the develop generation, grow up and fall off will seriously affect the machined surface roughness value. In addition, in cutting process due to the strong scraps and former knife friction role and tear phenomenon, but also in processing on the surface may produce scale thorn, make processing surface roughness increases.Grinding surface layer analysis of metallographic organization changes and grinding burns Mechanical processing produces in the process of heat cutting processing surface of workplace will make the rise of temperature of the violently, when the temperature more than the workplace material metallographic organization changes of the critical temperature, metallographic organization change will occur. In grinding processing, because most grits before cutting Angle is negative, grinding temperature is high, the quantity of heat of generation is much higher than cutting calories at, and grinding heat have 60 to 80% to the workplace, so very prone to the change of metallographic organization, makes the metal surface hardness and strength of decline, produce residual stress and even cause microcracks, this phenomenon is called grinding burns. Produce grinding burns, processing surface often appear yellow, brown, purple, green and burn color, this is grinding surface oxidation of high temperature in instantaneous film under color. Different burns color, shows that the surface of different levels by burns.Grinding hardened steel, workplace surface layer due to the role of the instantaneous heat, it may produce the following three metallographic organization changes:If grinding surface layer temperature not over phase transition temperature, but more than martensite transition temperature, then martensite will change to become low hardness of tempering methods, and meanwhile body or body, this call tempering burns.If grinding surface layer temperature more than phase transition temperatures, the martensite transformation for austenitic, at this time without cutting fluids, the grinding surface hardness fell sharply, surface was annealing, this phenomenon is called annealing burns. When dry grinding is easy to produce this kind of phenomenon.If grinding surface layer temperature more than phase transition temperature, but have thefull cutting fluid on the cooling, the grinding surface layer will be urgent cold forming secondary hardened martensitic, hardness than tempering martensite high, but the surface layer is very thin, and only a few microns thick, under which the low hardness for tempering saxhlet body and saxhlet body, make the surface layer general hardness still reduce, called quenching burns. Grinding burns improvement measureInfluence factors of grinding burns is grinding dosage, grinding wheel, the workpiecematerial and cooling conditions. Because grinding heat caused by grinding burns is the root cause of, because this wants to avoid grinding burns, should as far as possible to reduce the heat generated when grinding and decrease as far as possible to the quantity of heat of workplace. Specific can adopt the following measures:Choosing grinding reasonable dosage cannot use the too big grinding depth, because when grinding depth increases, the plastic deformation is increased, the surface layer and the temperature will increase, burns will also increase; The speed increase, a surface temperature will increase grinding zone, but due to the hot action time reduced, so can reduce the burn.The workplace material the workplace material grinding zone of the influence of the temperature of depends primarily on its hardness and strength, toughness and thermal conductivity. The workplace material hardness, the higher the strength, toughness, the bigger the grinding work when the more consumption, the quantity of heat that produced the more, the easy generation burns; Thermal conductivity of poor material, also easy to appear in the grinding burns.The choice of high hardness of the grinding wheel grinding wheel, passivated grits is not easy to fall off, easy to produce burns, so with soft grinding wheel is better; Choose coarse granularity grinding wheel grinding, not easily by grinding wheel grinding jams, can reduce burned; Combine agent of grinding burns also has a great influence, resin combination agent than ceramic combination agent easy to produce burns, rubber binder than resin binder are more likely to have burned.Cooling conditions for reduction in grinding of temperature, widely used in this cutting liquid cooling. In order to make cutting fluids can injection to the surface, usually the cutting fluid flow increase.中文译文影响工件表面质量的因素加工过程对表面质量的影响工艺系统的振动对工件表面质量的影响在机械加工过程中工艺系统有时会发生振动,即在刀具的切削刃与工件上正在切削的表面之间除了名义上的切削运动之外,还会出现一种周期性的相对运动。

机床——机械类外文文献翻译、中英文翻译

机床——机械类外文文献翻译、中英文翻译

毕业设计(论文)外文资料翻译系部:专业:姓名:学号:外文出处:English For Electromechanical(用外文写)Engineering附件:1.外文资料翻译译文;2.外文原文。

附件1:外文资料翻译译文机床机床是用于切削金属的机器。

工业上使用的机床要数车床、钻床和铣床最为重要。

其它类型的金属切削机床在金属切削加工方面不及这三种机床应用广泛。

车床通常被称为所有类型机床的始祖。

为了进行车削,当工件旋转经过刀具时,车床用一把单刃刀具切除金属。

用车削可以加工各种圆柱型的工件,如:轴、齿轮坯、皮带轮和丝杠轴。

镗削加工可以用来扩大和精加工定位精度很高的孔。

钻削是由旋转的钻头完成的。

大多数金属的钻削由麻花钻来完成。

用来进行钻削加工的机床称为钻床。

铰孔和攻螺纹也归类为钻削过程。

铰孔是从已经钻好的孔上再切除少量的金属。

攻螺纹是在内孔上加工出螺纹,以使螺钉或螺栓旋进孔内。

铣削由旋转的、多切削刃的铣刀来完成。

铣刀有多种类型和尺寸。

有些铣刀只有两个切削刃,而有些则有多达三十或更多的切削刃。

铣刀根据使用的刀具不同能加工平面、斜面、沟槽、齿轮轮齿和其它外形轮廓。

牛头刨床和龙门刨床用单刃刀具来加工平面。

用牛头刨床进行加工时,刀具在机床上往复运动,而工件朝向刀具自动进给。

在用龙门刨床进行加工时,工件安装在工作台上,工作台往复经过刀具而切除金属。

工作台每完成一个行程刀具自动向工件进给一个小的进给量。

磨削利用磨粒来完成切削工作。

根据加工要求,磨削可分为精密磨削和非精密磨削。

精密磨削用于公差小和非常光洁的表面,非精密磨削用于在精度要求不高的地方切除多余的金属。

车床车床是用来从圆形工件表面切除金属的机床,工件安装在车床的两个顶尖之间,并绕顶尖轴线旋转。

车削工件时,车刀沿着工件的旋转轴线平行移动或与工件的旋转轴线成一斜角移动,将工件表面的金属切除。

车刀的这种位移称为进给。

车刀装夹在刀架上,刀架则固定在溜板上。

溜板是使刀具沿所需方向进行进给的机构。

机械类外文文献翻译机械类英文翻译机械专业毕业设计中英文翻译机械专业中英文翻译机械专业英文翻译(优.选)

机械类外文文献翻译机械类英文翻译机械专业毕业设计中英文翻译机械专业中英文翻译机械专业英文翻译(优.选)

中英文翻译原文:Comment on medicines and chemical reagents package machineryconceptual designIn recent years, Carry out GMP (medicines and chemical reagents produces specifications of quality) attestation system because of sustained our country economic situation rise and country to pharmacy industry mandatory. Medicines and chemical reagents package machinery has got quite great progress. The new product increases by gradually. Engineering level has had very big improvement. But be returning very big gaps back to existence compared with international standards. Level being close to 60%'s product cannot to reach upper developed country century eighties. Large-scale advanced equipment is dependent on entrance mainly. Low our country medicines and chemical reagents package machinery engineering level is that the design designing personnel low level from our country enterprise arouses to a great extent.One, our country medicines and chemical reagents package machinery current situation analysesOur country medicines and chemical reagents package machinery still has bigger gap compared with advanced international level. What time is insufficient on domestic medicines and chemical reagents package machinery design under main existence1) Backward domestic mechanical performance medicines and chemical reagents package machinery mostly, accuracy low velocity, is slow, stationarity dispatches package machinery travel process to contain large amount of dyadic complicated intermittence motion. Come to come true mainly from the cam, the connecting rod. But, many design that the personnel is unable to require that the independence designs the parameter calculating cam bar linkage kinematics and dynamics according to job cycle picture and accuracy. Be only the surveying and mapping carrying out a piecemeal that the abroad model machine cam connecting rod part is dismantled down simplely. Bring about actuating mechanism error is very big. That domestic medicines and chemical reagents package machinery runs speed mostly is more general than hanging down according to cutting frequency if the aluminium moulds bubble coverpacker's for 100 one 300 mins, full-automatic medicine box packer dress box speed 50- 200 boxes/ ms in. But, on the international, the advanced aluminium moulds rushing steeping cover packer cutting frequency be able to reach 600 mins. Full-automatic medicine box packer dress box speed is able to reach 600 ~ 800 box/ mins. Not only working speed of domestic medicines and chemical reagents package machinery is slow. And, the partner has bigger noise.2) Is under the control of horizontal backward. Domestic medicines and chemical reagents package machinery controls low, automation of level difference mostly , the malfunction leads height. (Main package machinery finger box dress controls domestic medicines and chemical reagents with drinking wine holding machinery with) adopt PLC to do a scene mostly. But, advanced medicines and chemical reagents package machinery realizes supervisory control abroad mostly from computer system. Under the control of horizontal relatively backward. Great majority domestic medicines and chemical reagents package machinery automation sex is relatively poor. Adopt a single to produce a pattern first commonly. The full-automatic production line is few. Two is that full-automation works cannot to achieve. Require that the manpower feeds in raw material. Hand movement enchases. If in a little paper box packer, Page, paper box all needs medicine board , specifications paper to move charging personally. And require specially-assigned person to pay attention to if specifications, medicine board, paper box already finish using at any time. Happen to avoid bringing about machine racing or bringing about incomplete specifications, medicine board, and medicine box phenomenon. Other, domestic medicines and chemical reagents package mechanic failure rates are higher. Control a component (if the relay, electromagnetic valve, contactor, breaker etc.) etc. are often easy to damage. Halt also to frequently occur the malfunction.3) Functions are unitary, expansion sex is bad. Medicines and chemical reagents package machinery is that the form designs that specifically for specially appointed package. The general specification range inner in regulation is adjustable. But, a lot of our country medicines and chemical reagents package machinery considers insufficiency when designing that. Be not that reforming going a step further sets apart sufficient space. Cause the machinery designing that to be able to only adapt to the form board in several kinds simplicities. Change not adapting to wrapping material or the form board dimension. Fit in with even. The package finished product mass giving birth to a child is neither nice.4) Considers deficiency synthetically. Resource does not fully utilize. Our country medicines and chemical reagents there exists the chaos phenomenon in package machinery design. A lot of machinery designs that the personnel drags to the electric motor moving the synchrony technology, the servo drive technology do not knows. The problem simple electrical equipment available is resolved uses complicated mechanism to come to come true but. Some though the control organ works to come having adopt the synchrony electric motor to wait for a device. But choose block of wood ding-dang. The maximum having brought about resource not only wastes this condition. And make machinery function designing that low.5) Model is inflexible. Model seldom considering machinery time medicines and chemical reagents of our country package machinery design. Many machine molding that the manufacturer produces is not beautiful do not have model even. Give person feeling to rigid, to inflexible, not to have vigor. A few medicine box packers are middle. The nut all assembles screw on the machine outside board. But, the oil cup and flow nipple that a little lubrication uses also can be seen everywhere. Be stained fully with a greasy dirt easy to use machine everywhere time oiling. Impression is rough to person. No beautiful.Two, medicines and chemical reagents package machinery conceptual design contentPeople long-term study passes. Define conceptual design being: "Have been ascertaining the mission queen. Pass abstract-relation. Design the function structure. Explore appropriate effect principle and their combination waiting. Ascertain out basic finding the solution approach. Reach find the solution scheme. This part of the conceptual design designing that the job is called conceptual design is referred to make the queen who designs purpose and now has condition clear. The designer searches for many-sided knowledge. Analysis abstracts the solution on generating dyadic broad frame significance the day after tomorrow. Medicines and chemical reagents package machinery conceptual design demands according to each product life cycle stages. Carrying out the product function creates , the function breaks up as well as the function and son are functional physical design: That conception and systematization carrying out the scheme satisfying the operating principle that the function and structure demand finding the solution and carrying out the operating principle carrier realizing the function structure's design the conceptual design process is that one finds the solution realizing a function's , satisfies the various technologyand various there existing in economic target's , possibility scheme well ultimate for sure synthetically optimum scheme process. The conceptual design effect embodies in the product design early phase stage mainly. Chief architect is based on functional need of product but primitive conception and impulsion sprouting out form the product main body frame. And, it responds to every main module and module including. In order to accomplishing overall layout and the exterior, the first step designs that. And then carry out the optimization appraising a sum. Ascertain the overall design plan. Design that the personnel carries out the chief architect design thought going to designing middle concretely again from every part. Detail designs realization. The conceptual design putting medicines and chemical reagents package machinery into practice demands to design that the personnel reinforces the cognition to medicines and chemical reagents package first. Deepen the connotation understanding medicines and chemical reagents packages. Introduce modern package idea. Be in line with the international conventions actively. Modern package is to ensure the product safety not only. Make product transportation convenient. And be getting up propagate, environmental protection, defends against false. Attractive looks waits for the many-sided effect. Wrap up contents additional information. The medicines and chemical reagents package machinery design personnel should show solicitude for development of package system closely. Go deep into the handicraft studying package. Know demand of development of wrapping material and the person to machinery product very well. Only when such ability designs that out satisfy the high tone machinery product that the consumer demands. Medicines and chemical reagents package machinery conceptual design content has mainly:1) Makes the design mission clear. Be ready for feasibility analysis. The designer designs initial stage working in being in progress. Respond to the feasibility considering a product sufficiently. One aspect is the marketplace thinking. Include the production marketing, product raw material, the fabricating cost thinking: Another aspect is thinking that the product processes. Include thinking now having a working ability, processing handicraft, processing the function and periphery supporting industry. Periphery supporting environment thinking points to the local enterprise working ability mainly processes level, heat treatment handicraft and the infrastructural facilities construction etc.2) Function design. Great majority our country medicines and chemical reagents package machinery is the same kind model copying to abroad. But peculiar nationalconditions because of our country existence. Must carry out appropriate reforming on the product. To satisfy request of our country. But fault blindly copy blindly. The machinery designing that is packed in, irrigates the dress function outside except needing to satisfy a box. We must consider the additional function packing machinery. If in package box should add a counting cup. The medicine spoon waits an utensil down. Be put into use with convenience of customers. In machine, kind of aspect developing can design comparatively advanced machinery. If sterile pack machinery, the package machinery retaining freshness etc.Can develop the corollary equipment selling complete sets of equipment and the post-processing at reduced prices in the medicines and chemical reagents package front.3) Functions decomposition. Medicines and chemical reagents package machinery belongs to the integration of machinery with electronics product. Should consider every function all round time design. Sort Er Yan. The medicines and chemical reagents package machinery function may divide 3 major parts being that organization moves, monitors biography feel, the information processing and controlling a function basically. The function subdivides organization motion according to may not kind with machine , packer may be molding , heat-seal , pressure trace mark, according to cutting 4 big functions if the aluminum moulds bubble cover. But, paper box package machinery may be that the box opens, paper box transfers, breaks tongue , functions such as inserting tongue , flattening and putting a batch number up mark poison board under paper folding, deducing paper feed. Want to consider machinery lubrication, safe functions such as running, packing hygiene of machinery too in the process of design. This demands the technology designing that the personnel considers detecting sufficiently. Brightness, machine, electricity integration technology, computer art. Intersection between the pneumatic technology, the logistics technology connection.4) Organization is designed. Be to realize the predetermined function. We need to use different organization. This needs the part synthesizing each considering a complete machine among one process. Use the product designing that while satisfying the usage request. Structure is simple, pragmatic. Medicines and chemical reagents package machinery organization designs time. Respond to the principle choosing appropriate organization motion and constituting. Think sufficiently to realize what specially appointed motion needs organization. If cam organization. Bar linkage. Cam bar linkage. Respond to the technology wielding separation drive at the same time.Think that the transmission shaft designs a problem (if castellated shaft and ladder axis etc.) and drive are systematic synthetically. Design that process middle should cut down the effect that the uncertainty factor brings about to the full. Messenger organization operation is stable. Design that machinery carries out kinetic methods of analysis answering now and then. With lifting, machinery runs speed and stationarity. Should think that various packing machinery, adjustable, holds the mistake, but expansion, stationarity as well as beautiful-rization besides. Run after machinery is deft but stable. Design process but consult package machinery design of all kinds strong point. Draw other machinery (if plastic machinery, prints machinery) merit at the same time. Design the outside except carrying out organization. Return approach back to the realization should think that every function is other. If vacuum, electrical equipment waits under the control of. To expect that optimum combination is a product's turn.5) System under the control of schemes design. In medicines and chemical reagents package machinery, a very important part is that real time detecting is back-off to every organization. To ensure that equipment operation is smooth. Now many machinery products has selected and used large amount of photo electricity switch being the detecting component. Equipment has such as PC detecting bubble cover system on some machinery and the like system. This need all designs that meticulously. And, the general naval company is an integral whole.Three, concluding remarksThe thought a concept is designed melts to enter medicines and chemical reagents package machinery design being able to fall off designing a fault. Shorten a design cycle. Accelerate the product exploitation. Make the product designing that more rational, have affinity, more suitable man-machine project more. It is also that the main means costing down and improving enterprise competition is short of passive competition aspect backward for improving medicines and chemical reagents package machinery design at the same time. To adapt to the challenge that "queen GMP times" brings about. Design that the personnel must take product conceptual design seriously. Deepen the significance understanding conceptual design's.译文论药品包装机械的概念设计近年来,由于我国经济形势的持续高涨和国家对制药行业强制性推行GMP(药品生产质量规范)认证制度,药品包装机械取得了长足的进步。

机械加工外文文献翻译

机械加工外文文献翻译

外文原文MACHINABILITYThe machinability of a material usually defined in terms of four factors:1、Surface finish and integrity of the machined part;2、Tool life obtained;3、Force and power requirements;4、Chip control.Thus, good machinability good surface finish and integrity, long tool life, and low force And power requirements. As for chip control, long and thin (stringy) cured chips, if not broken up, can severely interfere with the cutting operation by becoming entangled in the cutting zone.Because of the complex nature of cutting operations, it is difficult to establish relationships that quantitatively define the machinability of a material. In manufacturing plants, tool life and surface roughness are generally considered to be the most important factors in machinability. Although not used much any more, approximate machinability ratings are available in the example below.1、Machinability Of SteelsBecause steels are among the most important engineering materials (as noted in Chapter 5), their machinability has been studied extensively. The machinability of steels has been mainly improved by adding lead and sulfur to obtain so-calledfree-machining steels.Resulfurized and Rephosphorized steels. Sulfur in steels forms manganese sulfide inclusions (second-phase particles), which act as stress raisers in the primary shear zone. As a result, the chips produced break up easily and are small; this improves machinability. The size, shape, distribution, and concentration of these inclusions significantly influence machinability. Elements such as tellurium and selenium, which are both chemically similar to sulfur, act as inclusion modifiers in resulfurized steels.Phosphorus in steels has two major effects. It strengthens the ferrite, causing increased hardness. Harder steels result in better chip formation and surface finish.Note that soft steels can be difficult to machine, with built-up edge formation and poor surface finish. The second effect is that increased hardness causes the formation of short chips instead of continuous stringy ones, thereby improving machinability.Leaded Steels. A high percentage of lead in steels solidifies at the tip of manganese sulfide inclusions. In non-resulfurized grades of steel, lead takes the form of dispersed fine particles. Lead is insoluble in iron, copper, and aluminum and their alloys. Because of its low shear strength, therefore, lead acts as a solid lubricant (Section 32.11) and is smeared over the tool-chip interface during cutting. This behavior has been verified by the presence of high concentrations of lead on thetool-side face of chips when machining leaded steels.When the temperature is sufficiently high-for instance, at high cutting speeds and feeds (Section 20.6)—the lead melts directly in front of the tool, acting as a liquid lubricant. In addition to this effect, lead lowers the shear stress in the primary shear zone, reducing cutting forces and power consumption. Lead can be used in every grade of steel, such as 10xx, 11xx, 12xx, 41xx, etc. Leaded steels are identified by the letter L between the second and third numerals (for example, 10L45). (Note that in stainless steels, similar use of the letter L means “low carbon,” a condition that improves their corrosion resistance.)However, because lead is a well-known toxin and a pollutant, there are serious environmental concerns about its use in steels (estimated at 4500 tons of lead consumption every year in the production of steels). Consequently, there is a continuing trend toward eliminating the use of lead in steels (lead-free steels). Bismuth and tin are now being investigated as possible substitutes for lead in steels.Calcium-Deoxidized Steels. An important development is calcium-deoxidized steels, in which oxide flakes of calcium silicates (CaSo) are formed. These flakes, in turn, reduce the strength of the secondary shear zone, decreasing tool-chip interface and wear. Temperature is correspondingly reduced. Consequently, these steels produce less crater wear, especially at high cutting speeds.Stainless Steels. Austenitic (300 series) steels are generally difficult to machine. Chatter can be s problem, necessitating machine tools with high stiffness. However, ferritic stainless steels (also 300 series) have good machinability. Martensitic (400 series) steels are abrasive, tend to form a built-up edge, and require tool materials with high hot hardness and crater-wear resistance. Precipitation-hardening stainless steelsare strong and abrasive, requiring hard and abrasion-resistant tool materials.The Effects of Other Elements in Steels on Machinability. The presence of aluminum and silicon in steels is always harmful because these elements combine with oxygen to form aluminum oxide and silicates, which are hard and abrasive. These compounds increase tool wear and reduce machinability. It is essential to produce and use clean steels.Carbon and manganese have various effects on the machinability of steels, depending on their composition. Plain low-carbon steels (less than 0.15% C) can produce poor surface finish by forming a built-up edge. Cast steels are more abrasive, although their machinability is similar to that of wrought steels. Tool and die steels are very difficult to machine and usually require annealing prior to machining. Machinability of most steels is improved by cold working, which hardens the material and reduces the tendency for built-up edge formation.Other alloying elements, such as nickel, chromium, molybdenum, and vanadium, which improve the properties of steels, generally reduce machinability. The effect of boron is negligible. Gaseous elements such as hydrogen and nitrogen can have particularly detrimental effects on the properties of steel. Oxygen has been shown to have a strong effect on the aspect ratio of the manganese sulfide inclusions; the higher the oxygen content, the lower the aspect ratio and the higher the machinability.In selecting various elements to improve machinability, we should consider the possible detrimental effects of these elements on the properties and strength of the machined part in service. At elevated temperatures, for example, lead causes embrittlement of steels (liquid-metal embrittlement, hot shortness; see Section 1.4.3), although at room temperature it has no effect on mechanical properties.Sulfur can severely reduce the hot workability of steels, because of the formation of iron sulfide, unless sufficient manganese is present to prevent such formation. At room temperature, the mechanical properties of resulfurized steels depend on the orientation of the deformed manganese sulfide inclusions (anisotropy). Rephosphorized steels are significantly less ductile, and are produced solely to improve machinability.2、Machinability of Various Other MetalsAluminum is generally very easy to machine, although the softer grades tend to form a built-up edge, resulting in poor surface finish. High cutting speeds, high rakeangles, and high relief angles are recommended. Wrought aluminum alloys with high silicon content and cast aluminum alloys may be abrasive; they require harder tool materials. Dimensional tolerance control may be a problem in machining aluminum, since it has a high thermal coefficient of expansion and a relatively low elastic modulus.Beryllium is similar to cast irons. Because it is more abrasive and toxic, though, it requires machining in a controlled environment.Cast gray irons are generally machinable but are. Free carbides in castings reduce their machinability and cause tool chipping or fracture, necessitating tools with high toughness. Nodular and malleable irons are machinable with hard tool materials.Cobalt-based alloys are abrasive and highly work-hardening. They require sharp, abrasion-resistant tool materials and low feeds and speeds.Wrought copper can be difficult to machine because of built-up edge formation, although cast copper alloys are easy to machine. Brasses are easy to machine, especially with the addition pf lead (leaded free-machining brass). Bronzes are more difficult to machine than brass.Magnesium is very easy to machine, with good surface finish and prolonged tool life. However care should be exercised because of its high rate of oxidation and the danger of fire (the element is pyrophoric).Molybdenum is ductile and work-hardening, so it can produce poor surface finish. Sharp tools are necessary.Nickel-based alloys are work-hardening, abrasive, and strong at high temperatures. Their machinability is similar to that of stainless steels.Tantalum is very work-hardening, ductile, and soft. It produces a poor surface finish; tool wear is high.Titanium and its alloys have poor thermal conductivity (indeed, the lowest of all metals), causing significant temperature rise and built-up edge; they can be difficult to machine.Tungsten is brittle, strong, and very abrasive, so its machinability is low, although it greatly improves at elevated temperatures.Zirconium has good machinability. It requires a coolant-type cutting fluid,however, because of the explosion and fire.3、Machinability of Various MaterialsGraphite is abrasive; it requires hard, abrasion-resistant, sharp tools.Thermoplastics generally have low thermal conductivity, low elastic modulus, and low softening temperature. Consequently, machining them requires tools with positive rake angles (to reduce cutting forces), large relief angles, small depths of cut and feed, relatively high speeds, andproper support of the workpiece. Tools should be sharp.External cooling of the cutting zone may be necessary to keep the chips frombecoming “gummy” and sticking to the tools. Cooling can usually be achieved with a jet of air, vapor mist, or water-soluble oils. Residual stresses may develop during machining. To relieve these stresses, machined parts can be annealed for a period of time at temperatures ranging from C ︒80 to C ︒160 (F ︒175to F ︒315), and then cooled slowly and uniformly to room temperature.Thermosetting plastics are brittle and sensitive to thermal gradients duringcutting. Their machinability is generally similar to that of thermoplastics.Because of the fibers present, reinforced plastics are very abrasive and aredifficult to machine. Fiber tearing, pulling, and edge delamination are significant problems; they can lead to severe reduction in the load-carrying capacity of the component. Furthermore, machining of these materials requires careful removal of machining debris to avoid contact with and inhaling of the fibers.The machinability of ceramics has improved steadily with the development of nanoceramics (Section 8.2.5) and with the selection of appropriate processingparameters, such as ductile-regime cutting (Section 22.4.2).Metal-matrix and ceramic-matrix composites can be difficult to machine,depending on the properties of the individual components, i.e., reinforcing orwhiskers, as well as the matrix material.4、Thermally Assisted MachiningMetals and alloys that are difficult to machine at room temperature can bemachined more easily at elevated temperatures. In thermally assisted machining (hot machining), the source of heat —a torch, induction coil, high-energy beam (such as laser or electron beam), or plasma arc —is forces, (b) increased tool life, (c) use ofinexpensive cutting-tool materials, (d) higher material-removal rates, and (e) reduced tendency for vibration and chatter.It may be difficult to heat and maintain a uniform temperature distribution within the workpiece. Also, the original microstructure of the workpiece may be adversely affected by elevated temperatures. Most applications of hot machining are in the turning of high-strength metals and alloys, although experiments are in progress to machine ceramics such as silicon nitride.SUMMARYMachinability is usually defined in terms of surface finish, tool life, force and power requirements, and chip control. Machinability of materials depends not only on their intrinsic properties and microstructure, but also on proper selection and control of process variables.中文翻译机械加工一种材料的机械加工性通常以四种因素的方式定义:1、分的表面光滑度和表面完整性。

机械类外文文献及翻译

机械类外文文献及翻译

机械类外文文献及翻译(文档含中英文对照即英文原文和中文翻译)原文:GEAR AND SHAFT INTRODUCTIONAbstract:The important position of the wheel gear and shaft can't falter in traditional machine and modern machines.The wheel gear and shafts mainly install the direction that delivers the dint at the principal axis box. The passing to process to make them can is divided into many model numbers, using for many situations respectively. So we must be the multilayers to the understanding of the wheel gear and shaft in many ways .Key words: Wheel gear; ShaftIn the force analysis of spur gears, the forces are assumed to act in a single plane. We shall study gears in which the forces have three dimensions. The reason for this, in the case of helical gears, is that the teeth are not parallel to the axis of rotation. And in the case ofbevel gears, the rotational axes are not parallel to each other. There are also other reasons, as we shall learn.Helical gears are used to transmit motion between parallel shafts. The helix angle is the same on each gear, but one gear must have a right-hand helix and the other a left-hand helix. The shape of the tooth is an involute helicoid. If a piece of paper cut in the shape of a parallelogram is wrapped around a cylinder, the angular edge of the paper becomes a helix. If we unwind this paper, each point on the angular edge generates an involute curve. The surface obtained when every point on the edge generates an involute is called an involute helicoid.The initial contact of spur-gear teeth is a line extending all the way across the face of the tooth. The initial contact of helical gear teeth is a point, which changes into a line as the teeth come into more engagement. In spur gears the line of contact is parallel to the axis of the rotation; in helical gears, the line is diagonal across the face of the tooth. It is this gradual of the teeth and the smooth transfer of load from one tooth to another, which give helical gears the ability to transmit heavy loads at high speeds. Helical gears subject the shaft bearings to both radial and thrust loads. When the thrust loads become high or are objectionable for other reasons, it may be desirable to use double helical gears. A double helical gear (herringbone) is equivalent to two helical gears of opposite hand, mounted side by side on the same shaft. They develop opposite thrust reactions and thus cancel out the thrust load. When two or more single helical gears are mounted on the same shaft, the hand of the gears should be selected so as to produce the minimum thrust load.Crossed-helical, or spiral, gears are those in which the shaft centerlines are neither parallel nor intersecting. The teeth of crossed-helical fears have point contact with each other, which changes to line contact as the gears wear in. For this reason they will carry out very small loads and are mainly for instrumental applications, and are definitely not recommended for use in the transmission of power. There is on difference between a crossed heli : cal gear and a helical gear until they are mounted in mesh with each other. They are manufactured in the same way. A pair of meshed crossed helical gears usually have the same hand; that is ,a right-hand driver goes with a right-hand driven. In the design of crossed-helical gears, the minimum sliding velocity is obtained when the helix angle areequal. However, when the helix angle are not equal, the gear with the larger helix angle should be used as the driver if both gears have the same hand.Worm gears are similar to crossed helical gears. The pinion or worm has a small number of teeth, usually one to four, and since they completely wrap around the pitch cylinder they are called threads. Its mating gear is called a worm gear, which is not a true helical gear. A worm and worm gear are used to provide a high angular-velocity reduction between nonintersecting shafts which are usually at right angle. The worm gear is not a helical gear because its face is made concave to fit the curvature of the worm in order to provide line contact instead of point contact. However, a disadvantage of worm gearing is the high sliding velocities across the teeth, the same as with crossed helical gears.Worm gearing are either single or double enveloping. A single-enveloping gearing is onein which the gear wraps around or partially encloses the worm.. A gearing in which each element partially encloses the other is, of course, a double-enveloping worm gearing. The important difference between the two is that area contact exists between the teeth of double-enveloping gears while only line contact between those of single-enveloping gears. The worm and worm gear of a set have the same hand of helix as for crossed helical gears, but the helix angles are usually quite different. The helix angle on the worm is generally quite large, and that on the gear very small. Because of this, it is usual to specify the lead angle on the worm, which is the complement of the worm helix angle, and the helix angle on the gear; the two angles are equal for a 0-deg. Shaft angle.When gears are to be used to transmit motion between intersecting shaft, some of bevel gear is required. Although bevel gear are usually made for a shaft angle of 0 deg. They may be produced for almost any shaft angle. The teeth may be cast, milled, or generated. Only the generated teeth may be classed as accurate. In a typical bevel gear mounting, one of the gear is often mounted outboard of the bearing. This means that shaft deflection can be more pronounced and have a greater effect on the contact of teeth. Another difficulty, which occurs in predicting the stress in bevel-gear teeth, is the fact the teeth are tapered.Straight bevel gears are easy to design and simple to manufacture and give very good results in service if they are mounted accurately and positively. As in the case of squr gears, however, they become noisy at higher values of the pitch-line velocity. In these cases it is often go : od design practice to go to the spiral bevel gear, which is the bevel counterpart of thehelical gear. As in the case of helical gears, spiral bevel gears give a much smoother tooth action than straight bevel gears, and hence are useful where high speed are encountered.It is frequently desirable, as in the case of automotive differential applications, to have gearing similar to bevel gears but with the shaft offset. Such gears are called hypoid gears because their pitch surfaces are hyperboloids of revolution. The tooth action between such gears is a combination of rolling and sliding along a straight line and has much in common with that of worm gears.A shaft is a rotating or stationary member, usually of circular cross section, having mounted upon it such elementsas gears, pulleys, flywheels, cranks, sprockets, and other power-transmission elements. Shaft may be subjected to bending, tension, compression, or torsional loads, acting singly or in combination with one another. When they are combined, one may expect to find both static and fatigue strength to be important design considerations, since a single shaft may be subjected to static stresses, completely reversed, and repeated stresses, all acting at the same time.The word “shaft” covers numerous v ariations, such as axles and spindles. Anaxle is a shaft, wither stationary or rotating, nor subjected to torsion load. A shirt rotating shaft is often called a spindle.When either the lateral or the torsional deflection of a shaft must be held to close limits, the shaft must be sized on the basis of deflection before analyzing the stresses. The reason for this is that, if the shaft is made stiff enough so that the deflection is not too large, it is probable that the resulting stresses will be safe. But by no means should the designer assume that they are safe; it is almost always necessary to calculate them so that he knows they are within acceptable limits. Whenever possible, the power-transmission elements, such as gears or pullets, should be located close to the supporting bearings, This reduces the bending moment, and hence the deflection and bending stress.Although the von Mises-Hencky-Goodman method is difficult to use in design of shaft, it probably comes closest to predicting actual failure. Thus it is a good way of checking a shaft that has already been designed or of discovering why a particular shaft has failed in service. Furthermore, there are a considerable number of shaft-design problems in which the dimension are pretty well limited by other considerations, such as rigidity, and it is only necessary for the designer to discover something about the fillet sizes, heat-treatment,and surface finish and whether or not shot peening is necessary in order to achieve the required life and reliability.Because of the similarity of their functions, clutches and brakes are treated together. In a simplified dynamic representation of a friction clutch, or brake, two in : ertias I and I traveling at the respective angular velocities W and W, one of which may be zero in the case of brake, are to be brought to the same speed by engaging the clutch or brake. Slippage occurs because the two elements are running at different speeds and energy is dissipated during actuation, resulting in a temperature rise. In analyzing the performance of these devices we shall be interested in the actuating force, the torque transmitted, the energy loss and the temperature rise. The torque transmitted is related to the actuating force, the coefficient of friction, and the geometry of the clutch or brake. This is problem in static, which will have to be studied separately for eath geometric configuration. However, temperature rise is related to energy loss and can be studied without regard to the type of brake or clutch because the geometry of interest is the heat-dissipating surfaces. The various types of clutches and brakes may be classified as fllows:. Rim type with internally expanding shoes. Rim type with externally contracting shoes. Band type. Disk or axial type. Cone type. Miscellaneous typeThe analysis of all type of friction clutches and brakes use the same general procedure. The following step are necessary:. Assume or determine the distribution of pressure on the frictional surfaces.. Find a relation between the maximum pressure and the pressure at any point. Apply the condition of statical equilibrium to find (a) the actuating force, (b) the torque, and (c) the support reactions.Miscellaneous clutches include several types, such as the positive-contact clutches, overload-release clutches, overrunning clutches, magnetic fluid clutches, and others.A positive-contact clutch consists of a shift lever and two jaws. The greatest differences between the various types of positive clutches are concerned with the design of the jaws. To provide a longer period of time for shift action during engagement, the jaws may be ratchet-shaped, or gear-tooth-shaped. Sometimes a great many teeth or jaws are used, and they may be cut either circumferentially, so that they engage by cylindrical mating, or on the faces of the mating elements.Although positive clutches are not used to the extent of the frictional-contact type, they do have important applications where synchronous operation is required.Devices such as linear drives or motor-operated screw drivers must run to definite limit and then come to a stop. An overload-release type of clutch is required for these applications. These clutches are usually spring-loaded so as to release at a predetermined toque. The clicking sound which is heard when the overload point is reached is considered to be a desirable signal.An overrunning clutch or coupling permits the driven member of a machine to “freewheel” or “overrun” bec ause the driver is stopped or because another source of power increase the speed of the driven. This : type of clutch usually uses rollers or balls mounted between an outer sleeve and an inner member having flats machined around the periphery. Driving action is obtained by wedging the rollers between the sleeve and the flats. The clutch is therefore equivalent to a pawl and ratchet with an infinite number of teeth.Magnetic fluid clutch or brake is a relatively new development which has two parallel magnetic plates. Between these plates is a lubricated magnetic powder mixture. An electromagnetic coil is inserted somewhere in the magnetic circuit. By varying the excitation to this coil, the shearing strength of the magnetic fluid mixture may be accurately controlled. Thus any condition from a full slip to a frozen lockup may be obtained.齿轮和轴的介绍摘要:在传统机械和现代机械中齿轮和轴的重要地位是不可动摇的。

机械类外文文献翻译(中英文翻译)

机械类外文文献翻译(中英文翻译)

机械类外文文献翻译(中英文翻译)英文原文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 of materials 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 be recognized, 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 systemand 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 since many 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 allowedto flourish without a great number of constraints. Even though many impractical ideas may arise, it is usually easy to eliminate them in the early stages of design before firm details are required by manufacturing. 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 tous. These are 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 function will 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 may be needed to perform a function previously done by men, such as computation, assembly, or servicing. With the objective 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.When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive east. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strength of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles ofmechanics, such as those of statics for reaction forces and for the optimumutilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress。

机械制造工艺外文文献翻译、中英文翻译、外文翻译

机械制造工艺外文文献翻译、中英文翻译、外文翻译

中国地质大学长城学院本科毕业设计外文资料翻译系别:工程技术系专业:机械设计制造及其自动化姓名:侯亮学号:052115072015年 4 月 3 日外文资料翻译原文Introduction of MachiningHave a shape as a processing method, all machining process for the production of the most commonly used and most important method. Machining process is a process generated shape, in this process, Drivers device on the work piece material to be in the form of chip removal. Although in some occasions, the workpiece under no circumstances, the use of mobile equipment to the processing, However, the majority of the machining is not only supporting the workpiece also supporting tools and equipment to complete.Machining know the process has two aspects. Small group of low-cost production. For casting, forging and machining pressure, every production of a specific shape of the workpiece, even a spare parts, almost have to spend the high cost of processing. Welding to rely on the shape of the structure, to a large extent, depend on effective in the form of raw materials. In general, through the use of expensive equipment and without special processing conditions, can be almost any type of raw materials, mechanical processing to convert the raw materials processed into the arbitrary shape of the structure, as long as the external dimensions large enough, it is possible. Because of a production of spare parts, even when the parts and structure of the production batch sizes are suitable for the original casting, Forging or pressure processing to produce, but usually prefer machining.Strict precision and good surface finish, machining the second purpose is the establishment of the high precision and surface finish possible on the basis of. Many parts, if any other means of production belonging to the large-scale production, Well Machining is a low-tolerance and can meet the requirements of small batch production. Besides, many parts on the production and processing of coarse process to improve its general shape of the surface. It is only necessary precision and choose only the surface machining. For instance, thread, in addition to mechanical processing, almost no other processing method for processing. Another example is the blacksmith pieces keyhole processing, as well as training to be conducted immediately after the mechanical completion of the processing.Primary Cutting ParametersCutting the work piece and tool based on the basic relationship between the following four elements to fully describe : the tool geometry, cutting speed, feed rate, depth and penetration of a cutting tool.Cutting Tools must be of a suitable material to manufacture, it must be strong, tough, hard and wear-resistant. Tool geometry -- to the tip plane and cutter angle characteristics -- for each cutting process must be correct.Cutting speed is the cutting edge of work piece surface rate, it is inches per minute toshow. In order to effectively processing, and cutting speed must adapt to the level of specific parts -- with knives. Generally, the more hard work piece material, the lower the rate.Progressive Tool to speed is cut into the work piece speed. If the work piece or tool for rotating movement, feed rate per round over the number of inches to the measurement. When the work piece or tool for reciprocating movement and feed rate on each trip through the measurement of inches. Generally, in other conditions, feed rate and cutting speed is inversely proportional to.Depth of penetration of a cutting tool -- to inches dollars -- is the tool to the work piece distance. Rotary cutting it to the chip or equal to the width of the linear cutting chip thickness. Rough than finishing, deeper penetration of a cutting tool depth.Rough machining and finishing machiningThere are two kinds of cuts in machine- shop work called, respectively, the "roughing cut" and the "finishing cut". When a piece is "roughed out", it is quite near the shape and size required, but enough metal has been left on the surface to finish smooth and to exact size." Generally speaking, bars of steel, forging, castings, etc. are machined to the required shape and size with only one roughing and one finishing cut. Sometimes, however, certain portions of a piece may require more than one roughing cut. Also, in some jobs, for example, when great accuracy is not needed, or when a comparatively small amount of metal must be removed, a finishing cut may be all that is required. The roughing cut, to remove the greater part of the excess material, should be reasonably heavy, that is, all the machine, or cutting tool, or work, or all three, will stand. So the machinist’s purpose is to remove the excess stock as fast as he can without leaving, at the same time, a surface too torn and rough, without bending the piece if it is slender, and without spoiling the centers. The finishing cut, to make the work smooth and accurate, is a finer cut. The emphasis here is refinement - very sharp tool, comparatively little metal removed, and a higher degree of accuracy in measurement. Whether roughing or finishing, the machinist must set the machine for the given job. He must consider the size and shape of the work and the kind of material, also the kind of tool used and the nature of the cut to be made, then he proceeds to set the machine for the correct speed and feed and to set the tool to take the depth of cut desired.Automatic Fixture Design外文资料翻译译文机械制造工艺机械加工是所有制造过程中最普遍使用的而且是最重要的方法。

精密机械加工工艺设计外文文献翻译

精密机械加工工艺设计外文文献翻译

精密机械加工工艺设计外文文献翻译In the process of machining。

the XXX cutting force。

centrifugal force。

inertia force。

etc。

In order to ensure that the workpiece XXX external forces。

XXX displacement。

XXX workpiece.XXX Clamping DeviceThere are many types of clamping devices。

but their XXX.1.Power DeviceThe source of clamping force XXX force。

The device that can generate force is called the power device of the XXX used power devices include pneumatic devices。

hydraulic devices。

electric devices。

ic devices。

gas-liquid linkage devices。

XXX。

it does not have a power device.2.Clamping PartThe part that accepts and transfers the original force and transforms it into clamping force and performs XXX consists of the following mechanisms:1) Mechanisms that accept the original force。

such as handles。

nuts。

and mechanisms used to connect the XXX.2) Intermediate force transfer mechanisms。

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Overall position of Agricultural Mechanization inTurkeyAgricultural equipment and machinery are the indispensable part of agricultural activities. If these instruments, which are used in various stages of production, are not used properly, there may be some problems. So, how can we use them properly ? As the proverb goes, “It is the want of care that makes the field bare”. They return the money and efforts invested in them if they are maintained well.Ploughs, which were being used in our country up until recently, resemble those ploughs of the various tribes that lived in Anatolia long time ago. It is because one society gets use of societies that lived before. Some of the black ploughs that were being used up until recently resemble the ploughs that had been used in the ancient Rome.The first agricultural school was established in the Ottoman Empire in 1846. The first domestic heavy ploughs was manufactured i n Izmir 90 years ago, and tractor was introduced 80 years ago. However, it was only the foundation of the Republic that the tractor began to be used in agricultural activities. Agricultural mobilization began with modern agricultural practices in the Atatürk Forest Farm, which was founded by the Great Atatürk. Use of modern agricultural equipment was encouraged, workshops and factories were established, and agricultural machinery was manufactured. Introduction of tractor and particularly its use in agricultural production began in 1938. In those years, tractor use in State Production Farms increased, and farmers recognized the benefits of tractor in agricultural productivity and labor. State production farms became places which clearly showed the importance of agricultural mechanization.Agricultural mechanization is a production technology which enables the appropriate use of energy and equipment required for high production in agricultural area.Warehousing, transporting and marketing the products have become faster and more economic with the help of agricultural mechanization.Tractor is the basic equipment that enables the use of other agricultural equipment. These equipment items are also produced in Turkey. As tractor and other mechanization equipment are expensive, they should be used in a way to achieve the highest productivity and managed by informed and efficient people.Agricultural production in Turkey is Cereal-BasedAgricultural production in Turkey is cereal-based. There are serious nutrition problems in more than the half of the developing countries. Every year, millions of people die of hunger. For this reason, agricultural production is highly important. Turkey is out of it’s available planting areas. They do not have any new places left for plantation. The only thing they can do is to increase productivity. In order to increase productivity, they need to use some imputs. The only way to increase these inputs such as fertilizers, chemicals, irrigation and high quality seedling is agricultural mechanization. It is achieved through ploughing the soil in the right time, planting with a particular plantation row and particular distance in order to utilize equally from all parts of soil, applying chemicals and fertilizers at the requested time and amount, harvesting in a short period and without loss of any grains, and storing the product.Necessary support is given to Turkey’s companiesAgricultural mechanization tools are expensive. However, if they are maintained well and used economically, they return their cost. State provides some opportunities such as low-interest rates for the procurement of Agricultural Mechanization Machineries. The equipment and machinery, which can be purchased with credits, are examined by the units established by the Ministry of Agriculture and Rural Affairs to be approved for the agricultural technique. In these institutions, all kinds of tools and machinery, including tractors, go under various tests. It is determined if these machines are appropriate for Turkey’s environment. Necessary support is given to Turkey’s companies and farmers in order to remove the deficiencies determined.As for the maintenance of these equipment and machinery, it is a great chance that via the improvement of technology, Turkey’s producers are provided withopportunities that will help them in agricultural activities. According to researches,if the maintenance of a machine is done right and on time, purchasing cost decreased by 1/5.农业机械化在土耳其的整体地位农业设备和机械在农业活动中是不可或缺的组成部分。

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