模具设计和制造外文文献翻译、中英文翻译、外文翻译

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常用研磨机外文文献翻译、中英文翻译、外文翻译

常用研磨机外文文献翻译、中英文翻译、外文翻译

常用研磨机外文文献翻译、中英文翻译、外文翻译Grinding machine is a crucial n processing method that offers high machining accuracy and can process a wide range of materials。

It is suitable for almost all kinds of material processing。

and can achieve very high n and shape accuracy。

even reaching the limit。

The machining accuracy of grinding device is simple and does not require complex ___.2.Types of Grinding MachinesGrinding machines are mainly used for n grinding of workpiece planes。

cylindrical workpiece surfaces (both inside and outside)。

tapered faces inside。

spheres。

thread faces。

and other types of ___ grinding machines。

including disc-type grinding machines。

shaft-type grinding machines。

ic grinding machines。

and special grinding machines.3.Disc-type Grinding MachineThe disc-type grinding machine is a type of grinding machine that uses a grinding disc to grind the ___。

注塑模具设计外文翻译

注塑模具设计外文翻译

毕业设计(论文)外文资料翻译及原文(2012届)题目电话机三维造型与注塑模具设计指导教师院系工学院班级学号姓名二〇一一年十二月六日【译文一】塑料注塑模具并行设计Assist.Prof.Dr. A. Y AYLA /Prof.Dr. Paş a YAYLA摘要塑料制品制造业近年迅速成长。

其中最受欢迎的制作过程是注塑塑料零件。

注塑模具的设计对产品质量和效率的产品加工非常重要。

模具公司想保持竞争优势,就必须缩短模具设计和制造的周期。

模具是工业的一个重要支持行业,在产品开发过程中作为一个重要产品设计师和制造商之间的联系。

产品开发经历了从传统的串行开发设计制造到有组织的并行设计和制造过程中,被认为是在非常早期的阶段的设计。

并行工程的概念(CE)不再是新的,但它仍然是适用于当今的相关环境。

团队合作精神、管理参与、总体设计过程和整合IT工具仍然是并行工程的本质。

CE过程的应用设计的注射过程包括同时考虑塑件设计、模具设计和注塑成型机的选择、生产调度和成本中尽快设计阶段。

介绍了注射模具的基本结构设计。

在该系统的基础上,模具设计公司分析注塑模具设计过程。

该注射模设计系统包括模具设计过程及模具知识管理。

最后的原则概述了塑料注射模并行工程过程并对其原理应用到设计。

关键词:塑料注射模设计、并行工程、计算机辅助工程、成型条件、塑料注塑、流动模拟1、简介注塑模具总是昂贵的,不幸的是没有模具就不可能生产模具制品。

每一个模具制造商都有他/她自己的方法来设计模具,有许多不同的设计与建造模具。

当然最关键的参数之一,要考虑到模具设计阶段是大量的计算、注射的方法,浇注的的方法、研究注射成型机容量和特点。

模具的成本、模具的质量和制件质量是分不开的在针对今天的计算机辅助充型模拟软件包能准确地预测任何部分充填模式环境中。

这允许快速模拟实习,帮助找到模具的最佳位置。

工程师可以在电脑上执行成型试验前完成零件设计。

工程师可以预测过程系统设计和加工窗口,并能获得信息累积所带来的影响,如部分过程变量影响性能、成本、外观等。

塑料模具注射成型中英文翻译、外文翻译、外文文献翻译

塑料模具注射成型中英文翻译、外文翻译、外文文献翻译

外文翻译原文:Injection MoldingMany different processes are used to transform plastic granules, powders, and liquids into product. The plastic material is in moldable form, and is adaptable to various forming methods. In most cases thermosetting materials require other methods of forming. This is recognized by the fact that thermoplastics are usually heated to a soft state and then reshaped before cooling. Theromosets, on the other hand have not yet been polymerized before processing, and the chemical reaction takes place during the process, usually through heat, a catalyst, or pressure. It is important to remember this concept while studying the plastics manufacturing processes and polymers used.Injection molding is by far the most widely used process of forming thermoplastic materials. It is also one of the oldest. Currently injection molding accounts for 30% of all plastics resin consumption. Since raw material can be converted by a single procedure, injection molding is suitable for mass production of plastics articles and automated one-step production of complex geometries. In most cases, finishing is not necessary. Typical products include toys, automotive parts, household articles, and consumer electronics goods.Since injection molding has a number of interdependent variables, it is a process of considerable complexity. The success of the injection molding operation is dependent not only in the proper setup of the machine hydraulics, barrel temperature variations, and changes in material viscosity. Increasing shot-to-shot repeatability of machine variables helps produce parts with tighter tolerance, lowers the level of rejects, and increases product quality (i.e., appearance and serviceability).The principal objective of any molding operation is the manufacture of products: to a specific quality level, in the shortest time, and using repeatable and fully automaticcycle. Molders strive to reduce or eliminate rejected parts in molding production. For injection molding of high precision optical parts, or parts with a high added value such as appliance cases, the payoff of reduced rejects is high.A typical injection molding cycle or sequence consists of five phases;1. Injection or mold filling2. Packing or compression3. Holding4. Cooling5. Part ejectionPlastic granules are fed into the hopper and through an in the injection cylinder where they are carried forward by the rotating screw. The rotation of the screw forces the granules under high pressure against the heated walls of the cylinder causing them to melt. As the pressure building up, the rotating screw is forced backward until enough plastic has accumulated to make the shot. The injection ram (or screw) forces molten plastic from the barrel, through the nozzle, sprue and runner system, and finally into the mold cavities. During injection, the mold cavity is filled volumetrically. When the plastic contacts the cold mold surfaces, it solidifies (freezes) rapidly to produce the skin layer. Since the core remains in the molten state, plastic follows through the core to complete mold filling. Typically, the cavity is filled to 95%~98% during injection. Then the molding process is switched over to the packing phase.Even as the cavity is filled, the molten plastic begins to cool. Since the cooling plastic contracts or shrinks, it gives rise to defects such as sink marks, voids, and dimensional instabilities. To compensate for shrinkage, addition plastic is forced into the cavity. Once the cavity is packed, pressure applied to the melt prevents molten plastic inside the cavity from back flowing out through the gate. The pressure must be applied until the gate solidifies. The process can be divided into two steps (packing and holding) or may be encompassed in one step(holding or second stage). During packing, melt forced into the cavity by the packing pressure compensates for shrinkage. With holding, the pressure merely prevents back flow of the polymer malt.After the holding stage is completed, the cooling phase starts. During, the part is held in the mold for specified period. The duration of the cooling phase depends primarily on the material properties and the part thickness. Typically, the part temperature must cool below the material’s ejection temperature. While cooling the part, the machine plasticates melt for the next cycle.The polymer is subjected to shearing action as well as the condition of the energy from the heater bands. Once the short is made, plastication ceases. This should occur immediately before the end of the cooling phase. Then the mold opens and the part is ejected.When polymers are fabricated into useful articles they are referred to as plastics, rubbers, and fibers. Some polymers, for example, cotton and wool, occur naturally, but the great majority of commercial products are synthetic in origin. A list of the names of the better known materials would include Bakelite, Dacron, Nylon, Celanese, Orlon, and Styron.Previous to 1930 the use of synthetic polymers was not widespread. However, they should not be classified as new materials for many of them were known in the latter half of the nineteenth century. The failure to develop them during this period was due, in part, to a lack of understanding of their properties, in particular, the problem of the structure of polymers was the subject of much fruitless controversy.Two events of the twentieth century catapulted polymers into a position of worldwide importance. The first of these was the successful commercial production of the plastic now known as Bakelite. Its industrial usefulness was demonstrated in1912 and in the next succeeding years. Today Bakelite is high on the list of important synthetic products. Before 1912 materials made from cellulose were available, but their manufacture never provided the incentive for new work in the polymer field such as occurred after the advent of Bakelite. The second event was concerned with fundamental studies of the nature polymers by Staudinger in Europe and by Carohers, who worked with the Du Pont company in Delaware. A greater part of the studies were made during the 1920’s. Staudinger’s work was primarily fundamental. Carother’s achievements led to the development of our present huge plastics industry by causing an awakening of interest in polymer chemistry, an interest which is still strongly apparent today.The Nature of ThermodynamicsThermodynamics is one of the most important areas of engineering science used to explain how most things work, why some things do not the way that they were intended, and why others things just cannot possibly work at all. It is a key part of the science engineers use to design automotive engines, heat pumps, rocket motors, power stations, gas turbines, air conditioners, super-conducting transmission lines, solar heating systems, etc.Thermodynamics centers about the notions of energy, the idea that energy is conserved is the first low of thermodynamics. It is starting point for the science of thermodynamics is entropy; entropy provides a means for determining if a process is possible.This idea is the basis for the second low of thermodynamics. It also provides the basis for an engineering analysis in which one calculates the maximum amount of useful that can be obtained from a given energy source, or the minimum amount of power input required to do a certain task.A clear understanding of the ideas of entropy is essential for one who needs to use thermodynamics in engineering analysis. Scientists are interested in using thermodynamics to predict and relate the properties of matter; engineers are interested in using this data, together with the basic ideas of energy conservation and entropy production, to analyze the behavior of complex technological systems.There is an example of the sort of system of interest to engineers, a large central power stations. In this particular plant the energy source is petroleum in one of several forms, or sometimes natural gas, and the plant is to convert as much of this energy as possible to electric energy and to send this energy down the transmission line.Simply expressed, the plant does this by boiling water and using the steam to turn a turbine which turns an electric generator.The simplest such power plants are able to convert only about 25 percent of the fuel energy to electric energy. But this particular plant converts approximately 40 percent;it has been ingeniously designed through careful application of the basic principles of thermodynamics to the hundreds of components in the system.The design engineers who made these calculations used data on the properties of steam developed by physical chemists who in turn used experimental measurements in concert with thermodynamics theory to develop the property data.Plants presently being studied could convert as much as 55 percent of the fuel energy to electric energy, if they indeed perform as predicted by thermodynamics analysis.The rule that the spontaneous flow of heat is always from hotter to cooler objects is a new physical idea. There is noting in the energy conservation principle or in any other law of nature that specifies for us the direction of heat flow. If energy were to flow spontaneously from a block of ice to a surrounding volume of water, this could occur in complete accord with energy conservation. But such a process never happens. This idea is the substance of the second law of thermodynamics.Clear, a refrigerator, which is a physical system used in kitchen refrigerators, freezers, and air-conditioning units must obey not only the first law (energy conservation) but the second law as well.To see why the second law is not violated by a refrigerator, we must be careful in our statement of law. The second law of thermodynamics says, in effect, that heat never flows spontaneously from a cooler to a hotter object.Or, alternatively, heat can flow from a cooler to a hotter object only as a result of work done by an external agency. We now see the distinction between an everyday spontaneous process, such as the flow of heat from the inside to the outside of a refrigerator.In the water-ice system, the exchange of energy takes place spontaneously and the flow of heat always proceeds from the water to the ice. The water gives up energy and becomes cooler while the ice receives energy and melts.In a refrigerator, on the other hand, the exchange of energy is not spontaneous. Work provided by an external agency is necessary to reverse the natural flow of heat and cool the interior at the expense of further heating the warmer surroundings.译文:塑料注射成型许多不同的加工过程习惯于把塑料颗粒、粉末和液体转化成最终产品。

冲压模具成型外文翻译参考文献

冲压模具成型外文翻译参考文献

冲压模具成型外文翻译参考文献(文档含中英文对照即英文原文和中文翻译)4 Sheet metal forming and blanking4.1 Principles of die manufacture4.1.1 Classification of diesIn metalforming,the geometry of the workpiece is established entirely or partially by the geometry of the die.In contrast to machining processes,ignificantly greater forces are necessary in forming.Due to the complexity of the parts,forming is often not carried out in a single operation.Depending on the geometry of the part,production is carried out in several operational steps via one or several production processes such as forming or blanking.One operation can also include several processes simultaneously(cf.Sect.2.1.4).During the design phase,the necessary manufacturing methods as well as the sequence and number of production steps are established in a processing plan(Fig.4.1.1).In this plan,theavailability of machines,the planned production volumes of the part and other boundary conditions are taken into account.The aim is to minimize the number of dies to be used while keeping up a high level of operational reliability.The parts are greatly simplified right from their design stage by close collaboration between the Part Design and Production Departments in order to enable several forming and related blanking processes to be carried out in one forming station.Obviously,the more operations which are integrated into a single die,the more complex the structure of the die becomes.The consequences are higher costs,a decrease in output and a lower reliability.Fig.4.1.1 Production steps for the manufacture of an oil sumpTypes of diesThe type of die and the closely related transportation of the part between dies is determined in accordance with the forming procedure,the size of the part in question and the production volume of parts to be produced.The production of large sheet metal parts is carried out almost exclusively using single sets of dies.Typical parts can be found in automotive manufacture,the domestic appliance industry and radiator production.Suitable transfer systems,for example vacuum suction systems,allow the installation of double-action dies in a sufficiently large mounting area.In this way,for example,the right and left doors of a car can be formed jointly in one working stroke(cf.Fig.4.4.34).Large size single dies are installed in large presses.The transportation of the parts from oneforming station to another is carried out mechanically.In a press line with single presses installed one behind the other,feeders or robots can be used(cf.Fig.4.4.20 to 4.4.22),whilst in large-panel transfer presses,systems equipped with gripper rails(cf.Fig.4.4.29)or crossbar suction systems(cf.Fig.4.4.34)are used to transfer the parts.Transfer dies are used for the production of high volumes of smaller and medium size parts(Fig.4.1.2).They consist of several single dies,which are mounted on a common base plate.The sheet metal is fed through mostly in blank form and also transported individually from die to die.If this part transportation is automated,the press is called a transfer press.The largest transfer dies are used together with single dies in large-panel transfer presses(cf.Fig.4.4.32).In progressive dies,also known as progressive blanking dies,sheet metal parts are blanked in several stages;generally speaking no actual forming operation takes place.The sheet metal is fed from a coil or in the form of metal ing an appropriate arrangement of the blanks within the available width of the sheet metal,an optimal material usage is ensured(cf.Fig.4.5.2 to 4.5.5). The workpiece remains fixed to the strip skeleton up until the laFig.4.1.2 Transfer die set for the production of an automatic transmission for an automotive application-st operation.The parts are transferred when the entire strip is shifted further in the work flow direction after the blanking operation.The length of the shift is equal to the center line spacing of the dies and it is also called the step width.Side shears,very precise feeding devices or pilot pins ensure feed-related part accuracy.In the final production operation,the finished part,i.e.the last part in the sequence,is disconnected from the skeleton.A field of application for progressive blanking tools is,for example,in the production of metal rotors or stator blanks for electric motors(cf.Fig.4.6.11 and 4.6.20).In progressive compound dies smaller formed parts are produced in several sequential operations.In contrast to progressive dies,not only blanking but also forming operations areperformed.However, the workpiece also remains in the skeleton up to the last operation(Fig.4.1.3 and cf.Fig.4.7.2).Due to the height of the parts,the metal strip must be raised up,generally using lifting edges or similar lifting devices in order to allow the strip metal to be transported mechanically.Pressed metal parts which cannot be produced within a metal strip because of their geometrical dimensions are alternatively produced on transfer sets.Fig.4.1.3 Reinforcing part of a car produced in a strip by a compound die setNext to the dies already mentioned,a series of special dies are available for special individual applications.These dies are,as a rule,used separately.Special operations make it possible,however,for special dies to be integrated into an operational Sequence.Thus,for example,in flanging dies several metal parts can be joined together positively through the bending of certain metal sections(Fig.4.1.4and cf.Fig.2.1.34).During this operation reinforcing parts,glue or other components can be introduced.Other special dies locate special connecting elements directly into the press.Sorting and positioning elements,for example,bring stamping nuts synchronised with the press cycles into the correct position so that the punch heads can join them with the sheet metal part(Fig.4.1.5).If there is sufficient space available,forming and blanking operations can be carried out on the same die.Further examples include bending,collar-forming,stamping,fine blanking,wobble blanking and welding operations(cf.Fig.4.7.14 and4.7.15).Fig.4.1.4 A hemming dieFig.4.1.5 A pressed part with an integrated punched nut4.1.2 Die developmentTraditionally the business of die engineering has been influenced by the automotive industry.The following observations about the die development are mostly related to body panel die construction.Essential statements are,however,made in a fundamental context,so that they are applicable to all areas involved with the production of sheet-metal forming and blanking dies.Timing cycle for a mass produced car body panelUntil the end of the 1980s some car models were still being produced for six to eight years more or less unchanged or in slightly modified form.Today,however,production time cycles are set for only five years or less(Fig.4.1.6).Following the new different model policy,the demands ondie makers have also changed prehensive contracts of much greater scope such as Simultaneous Engineering(SE)contracts are becoming increasingly common.As a result,the die maker is often involved at the initial development phase of the metal part as well as in the planning phase for the production process.Therefore,a muchbroader involvement is established well before the actual die development is initiated.Fig.4.1.6 Time schedule for a mass produced car body panelThe timetable of an SE projectWithin the context of the production process for car body panels,only a minimal amount of time is allocated to allow for the manufacture of the dies.With large scale dies there is a run-up period of about 10 months in which design and die try-out are included.In complex SE projects,which have to be completed in 1.5 to 2 years,parallel tasks must be carried out.Furthermore,additional resources must be provided before and after delivery of the dies.These short periods call for pre-cise planning,specific know-how,available capacity and the use of the latest technological and communications systems.The timetable shows the individual activities during the manufacturing of the dies for the production of the sheet metal parts(Fig.4.1.7).The time phases for large scale dies are more or less similar so that this timetable can be considered to be valid in general.Data record and part drawingThe data record and the part drawing serve as the basis for all subsequent processing steps.They describe all the details of the parts to be produced. The information given in theFig.4.1.7 Timetable for an SE projectpart drawing includes: part identification,part numbering,sheet metal thickness,sheet metal quality,tolerances of the finished part etc.(cf.Fig.4.7.17).To avoid the production of physical models(master patterns),the CAD data should describe the geometry of the part completely by means of line,surface or volume models.As a general rule,high quality surface data with a completely filleted and closed surface geometry must be made available to all the participants in a project as early as possible.Process plan and draw developmentThe process plan,which means the operational sequence to be followed in the production of the sheet metal component,is developed from the data record of the finished part(cf.Fig.4.1.1).Already at this point in time,various boundary conditions must be taken into account:the sheet metal material,the press to be used,transfer of the parts into the press,the transportation of scrap materials,the undercuts as well as thesliding pin installations and their adjustment.The draw development,i.e.the computer aided design and layout of the blank holder area of the part in the first forming stage–if need bealso the second stage–,requires a process planner with considerable experience(Fig.4.1.8).In order to recognize and avoid problems in areas which are difficult to draw,it is necessary to manufacture a physical analysis model of the draw development.With this model,theforming conditions of the drawn part can be reviewed and final modifications introduced,which are eventually incorporated into the data record(Fig.4.1.9).This process is being replaced to some extent by intelligent simulation methods,through which the potential defects of the formed component can be predicted and analysed interactively on the computer display.Die designAfter release of the process plan and draw development and the press,the design of the die can be started.As a rule,at this stage,the standards and manufacturing specifications required by the client must be considered.Thus,it is possible to obtain a unified die design and to consider the particular requests of the customer related to warehousing of standard,replacement and wear parts.Many dies need to be designed so that they can be installed in different types of presses.Dies are frequently installed both in a production press as well as in two different separate back-up presses.In this context,the layout of the die clamping elements,pressure pins and scrap disposal channels on different presses must be taken into account.Furthermore,it must be noted that drawing dies working in a single-action press may be installed in a double-action press(cf.Sect.3.1.3 and Fig.4.1.16).Fig.4.1.8 CAD data record for a draw developmentIn the design and sizing of the die,it is particularly important to consider the freedom of movement of the gripper rail and the crossbar transfer elements(cf.Sect.4.1.6).These describe the relative movements between the components of the press transfer system and the die components during a complete press working stroke.The lifting movement of the press slide,the opening and closing movements of the gripper rails and the lengthwise movement of the whole transfer are all superimposed.The dies are designed so that collisions are avoided and a minimum clearance of about 20 mm is set between all the moving parts.4 金属板料的成形及冲裁4. 模具制造原理4.1.1模具的分类在金属成形的过程中,工件的几何形状完全或部分建立在模具几何形状的基础上的。

模具设计外文翻译

模具设计外文翻译

外文原文Abstract:Die designing is a demanding and hard work.To design a separate die for each product is time consuming and expensive task.This paper presents an idea of sets of standard reference dies.it gives a concept of flexible die designing using a reference standard die designed in a popular commercial CAD/CAM software—Pro/Engineer.Rather than designing a separate die for each part,just update the die design by selecting the die dimensions as required.The use of this concept will prove to reduce time and cost of product in manufacturing industry.Key words:die;flexible die designing system ;standardization;Pro/E;secondary developmentAt present, the industrial developed countries and regions in the mold industry has been gradually standardize and serialization. In China, although the majority die within the enterprises have business standards, but generally not high degree of standardization, standardization of stamping die in the die-limited parts of the parts. To achieve real savings stamping die design time and shorten the processing cycle, cost savings, reduce design and manufacturing staff workload purposes, it needs to develop a flexible stamping die design system. At the same time, stamping die serialization of the scope of standardization and can not be confined to die-part of the fixed panels, boards, the top plate unloading device commonly used components such as stamping or even die structure, we should achieve serialization and standardization.As CAD / CAM technology in the design and manufacture die in the course of extensive application, it should first be standardized stamping die from the CAD system began. Some large-scale commercialization of the CAD / CAM software, such as Pro / E, UG, and so on. Have developed a specialized injection mold design package. And stamping die design for the special software, users need to be developed.l The application tools Pro / E in stamping die design flexibility in the system developmentPro / Engineer by the United States has developed a set of PTC CAD / cAM / CAE software. Pro / E using a single database And feature-based, the design parameters of the model, provides users with 1 The development is very convenient for stamping die flexible system of tools juice1.1 Family TableFanaily Fable known as the Family Table, the structure used to create the same or similar parts of the size and characteristics of the standardized database tables, is devoted to the establishment of a standard parts library tool. The use of the formerfirst family table to create a generic representation of the components (the generic), according to the need to target and then added to the family table a series of management.Family sheet management can be the object of a size (dimension), features (feature), parameters (parameter) and assembly parts (component), and so on.A family table can have multiple levels, that is a generic parts can contain multiple sub-components (instance, also known as examples), and each Instance can contain their own Sub Instance. Discharge screw (stripper-bolt) the family table structure as shown in Figure 1.Figure 1 Family Table hierarchy1.2 RelationsRelations (relations) between mathematics and procedures, including grammar, and its main role is to be part or assembly of the relevance of the data by size symbols, and other parameters of grammar (syntax) to establish mathematical formula to meet the design requirements. Pro / E system of relations can be found in Sketch, Feature, Part and in the Assembly. Simple sentence, judgement and sentence is to establish relations of common format. Simple sentence that a simple mathematical relationship between the size of direct response associated situation. The use of simple format, such as d6 = L. BP 1 2 * d3. Judgement on the sentence for certain occasions, by specifying conditions to express design intent, grammar structure: "IF… ENDIF" or "IF… ELSE… ENDIF" in the "ELSE… ENDIF" between conditional statements can be multi-nested. Relations in the standardization and flexible stamping die design system in the building process plays a very important role, it has decided to parts of the geometric shape and characteristics of relations between the digital Xiao, partsrelations between the assembly and parts assembly in the presence of middle - A number of features.1.3 Pro/ProgramPro / Program (program) is the Pro / E of a procedural tool, similar to its grammar VBA and Office software in the Macro (Acer). When users use of Pro / engineer to design .The product of various kinds of information to document the format will be recorded. Through the Pro / Progran document editing, can be achieved on the characteristics of the hide, delete and re-order the assembly of components to add and replacement operation. These features stamping dies for the establishment of standard parts library, standards and flexible design structure of the system is very useful.Program files in the structure can be broadly classified into the title, set of parameters relationship, to add features (parts) and updating the quality attributes, such as five parts. In "INPUT… END INPUT" Xiao located between the parameters of the "RE1 ATIONS… ENDREALATIONS" relations between the various add in the "ADD… END ADD" and added features (part module) or parts (assembly module). Pro / Program provides three types of parameters: NUMBER (numerical) STRING (string) and YES-NO (it).2. Standards moldbase of the development2.1 Standards moldbase Classification and organizationsDie-stamping die is an important part. The typical model-there are three types: rear-guided-mode (back pillar sets), the middle-guided-mode (center pillar sets) and the guided-mode-angle (diagonal pillarsets). Each type of die-also includes a variety of specifications. According to Die boundary demarcation size, rear-guided, in a L ×B-22 specifications, D0 specifications 6 (L = B), middle-guided, in the nine-D0 specifications, the guided-mode-Kok L × B specifications 7 [2-3].In order to facilitate the management and data calls, the standard mode of the directory of the best-established in the Pro / E installation directory. As three categories-the larger structural differences, it may die-the root of the establishment of three other subdirectories, each subdirectory contains all the component parts-mode, and each type of parts can be adopted Pro / E Software for the family table, and toolssuch as the establishment of standard procedures for the database.2.2 Standards moldbase library buildingDie-stamping die from the main mode on the Block (upper.shoe), nder-Block (1 ower.shoe), I. column (guide.pillar) and I. Case (guidebushing), and other components. In order to make structural integrity of mold, can also die stalk (shank) assembly to die-in. Here are rear-die I.Establishment of the standard method.First of all the various components to create three-dimensional model, and then the standard manual data in the table a series of symbolic dimension added to the group on January 1 Editor (can also use Excel for editing). Add in the size of symbols, Size will be the best symbol to revise the manual and the size of the same symbol. Because people can not distinguish between Table Capitalization is, when both the same size letters, proposed to use capital letters to distinguish between pairs of characters, such as that for the d D, and D that will become a DD.Standard on two-Block: When the L ×B> 200 mm ×160 mn-i have installed Boss, and when L × B is less than or equal to the scope of non-installation of Boss, shown in Figure 2. Determine whether Boss in two ways: one way is to use Family Table, will generate the Boss Extrude Offset two characteristics and the way to Feature added to the family table, and in these two characteristics of the list Enter in the "Y" or "N", to determine the specifications of a certain mode on the Block, whether these two features; Another method is to find these two features in the Pro / Program in the location and characteristics of the process to add Extrude His statement before the judge "IF L> 200 1 B> 160", adding the Offset characteristics of the procedures used "END IF" the end of judgement.Figure2. die on the ground in two types2.3 The establishment of Standards moldbase forIn Pro / Assembly in the same module can be generated by the use of family die-standard database. Family structure in the assembly, when selected COrnponent, select the mode of all the parts-and enter a different group in the table-model specifications required by the standards of sub-components of the name, as shown in Figure 3.Figure 3 rear-guided, in the standard mode of Family TableCommon mode handles four types: pressure-in-stalk, the flange-stalk, Screw-mode and floating stems die stalk. If the four types of module assembly to handle all the common-mode model (Figure 3 in the assembly only two kinds), in the group table by the need to enter the module handles parts of the name, set the parameters of INPUT, with Regenerate Called when the parameters of renewable order to choose the mode of different types of handles. Of course, people can also die of the table do not have to handle characters with "N" to curb, as shown in Figure 3-mode system is used in this method.3 The development of standard stamping die3.1 The typical combination of stamping dieStamping die in the larger structural differences and establish flexible stamping die design systems using the best combination of the typical mold. Use of combinations to determine the structure of the typical mold of the structure, and thus determine the composition of the various components die sizes and assembly relations. Commonly used combination of stamping die typical structure: a fixed combinationof unloading, Tanya unloading combinations, composite model portfolio, such as plate-portfolio. Mold can not be separated from the structure of ISO standardization of parts, in the Pro / Engineer Dies in the standardization of parts can be used in the design of the bottom-up approach can also be used top-down design.3.2 die in the process of assembling data transferBecause of complicated, so stamping die by the standardization of the factors to consider-Modulus than standardized by many more factors to consider, one of the most important factor is the size of the correlation between the components. In the mold of a standard combination, assembly and components, parts and components between the need for data transmission, and in the Pro / Assembly can be very easy to achieve this objective.3.2.1 by the assembly of components to the data transferPro / Program can use the assembly EXECUTE statement will be down the parameters in a sub-assembly or parts delivery, the use of syntax is as follows: EXECUTE PART / ASSEMBLY file name components or sub-assembly of the parameters in the assembly of = END EXECUTE EXECUTE statement parameters can not leapfrog data transmission, not by the assembly to sub-assembly of components in the direct transmission of data.3.2.2 data transfer between the componentsWhen added to the assembly of components are in a Id, it can complete the assembly of components between the data transfer. Id assembly of components, can be used in the menu RELATIONs Session Id command to query. Figure 4 is the combination of Tanya discharge standards in the spring of unloading assembly diagram. As assembly to die in the spring have a pre-compression and thus the length of its assembly (Hs) are no longer equal to the length of freedom (H.). In determining H, you can use the following mathematical relationship:Hs:38= L:32一tbp:0In this way can always guarantee equal to the length of spring assembly from the surface to Dianban discharge board under the surface height, thus eliminating the relevant parts were replaced after the size of Laws. In the design of this mold is very practical, because the mold assembly in a similar situation there are many. Again, in determining the discharge screw on the seat-hole diameter (dI34), they can use thefollowing mathematical relationship:d134:8=D:32+2This Id, established by the mathematical relationship between the need to use Regenerate order to take effect, so different parts on the size of the location of as little as possible in this way, so as not to die in the initial call model will appear at the wrong result will be displayed. But if the parts in between and parameters to transfer data, the location of the various components of size parameters to create a mathematical relationship, the trouble can be avoided.3.2.3 standard replacement partsFamily Table used to establish the standard parts can lookup. inst Replacement statement. Lookup inst allows users to find the standard parts that match the sub-components, if not find the results, then return to a generic [4 J.Lookup.inst :lookup inst(generic—name,match-mode,paramnamel,match—valuel,param-name2,match—value2…)One match. preferred mode of three, representing different meanings: one is to find parameters of less than or equal to find the value of components; parameter values 0 to find an exact match to find value of the sub-components; to find parameters of greater than or equal to find value The sub-components.3.3 structure of the assemblyDie parts to complete the establishment and rationalize the assembly relations between the components, you can generate mold assembly model. Figure 5 for the development of the author Tanya unloading combination of specifications for the 200 mm × 160 mm of die structure (omit all the characteristics of thread).3.4 stamping die callStamping die in the Pro / Assembly call directly, but also can be used Pro / TOOLKIT development of visual user interface to call. Pro / TOOLKIT Pro Ecuador is the second development system software package, its main purpose is to allowusers or third parties through the expansion of C code Pro / E function, based on the development of Pro / E system of application modules to meet user Special needs. Pro/T00LKIT use of the UI dialog, the menu VC + + and Visual Interface technology, designed to facilitate flexible and practical stamping die design system for interactive interface. Use interface called the structure of various stamping dies, the choice of different specifications of the parts, enter a different parameters to determine sheet parameters as well as their positioning in the mold, and further in the system design punch, die and other structures, Thus greatly enhance the efficiency of stamping die design.4 ConclusionSince stamping process a wide range of complex processes, and the shape of various parts die, stamping dies in achieving standardization and development of flexible design system and the process is very complicated, but flexible stamping die design system of stamping die CAD is to improve the level of the cornerstones . Pro / E powerful components, the assembly of the criteria for the establishment of the functions of stamping dies for the standardization and flexible design of the feasibility of developing systems to provide a strong guarantee. In the development of flexible design system, should ingenious application of Pro / E software provided by an effective tool, considering the different types of standard structural composition of the assembly relations. Between the parts and components meet requirements of size structure changes, and the best use RELATIONS Pro / Program prepared by the mathematical relations systems and procedures to increase the flexibility and practicality. Die flexible design and application development system to avoid a mold designers unnecessary duplication of labor, so that the programme will focus on the concept, process optimization, and other creative work, thus mold the rapid design and production standards have a practical application Significance.外文资料翻译译文摘要:模具设计是一个苛刻的辛勤工作。

(完整版)冲压类外文翻译、中英文翻译冲压模具设计

(完整版)冲压类外文翻译、中英文翻译冲压模具设计

"sheet-metal forming". Sheet-metal forming ( also called stamping or pressing )is
is hard to imagine the scope and cost of these facilities without visiting an
Minimum bend radii vary for different metals, generally, different annealed metals
be bent to a radius equal to the thickness of the metal without cracking or
modes can be illustrated by considering the deformation of small sheet elements
Sheet forming a simple cup
the blank flange as it is being drawn horizontally through
Minimum bend radius for various materials at room temperature
Condition
Hard
0 6T
0 4T
0 2T
5T 13T
0.5T 6T
0.5T 4T
0.7T 3T
2.6T 4T
——thickness of material
one punch to prevent its buckling under pressure from the ram of the press.

模具设计与制造——外文翻译、中英文翻译

模具设计与制造——外文翻译、中英文翻译

Mold design and manufactureThe mold is the manufacturing industry important craft foundation, in our country, the mold manufacture belongs to the special purpose equipment manufacturing industry. China although very already starts to make the mold and the use mold, but long-term has not formed the industry. Straight stabs 0 centuries 80's later periods, the Chinese mold industry only then drives into the development speedway. Recent years, not only the state-owned mold enterprise had the very big development, the three investments enterprise, the villages and towns (individual) the mold enterprise's development also quite rapid .Although the Chinese mold industrial development rapid, but compares with the demand, obviously falls short of demand, its main gap concentrates precisely to, large-scale, is complex, the long life mold domain. As a result of in aspect and so on mold precision, life, manufacture cycle and productivity, China and the international average horizontal and the developed country still had a bigger disparity, therefore, needed massively to import the mold every year .The Chinese mold industry except must continue to sharpen the productivity, from now on will have emphatically to the profession internal structure adjustment and the state-of-art enhancement. The structure adjustment aspect, mainly is the enterprise structure to the specialized adjustment, the product structure to center the upscale mold development, to the import and export structure improvement, center the upscale automobile cover mold forming analysis and the structure improvement, the multi-purpose compound mold and the compound processing and the laser technology in the mold design manufacture application, the high-speed cutting, the superfinishing and polished the technology, the information direction develops .The recent years, the mold profession structure adjustment and the organizational reform step enlarges, mainly displayed in, large-scale, precise, was complex, the long life, center the upscale mold and the moldstandard letter development speed is higher than the common mold product; The plastic mold and the compression casting mold proportion increases; Specialized mold factory quantity and its productivity increase; "The three investments" and the private enterprise develops rapidly; The joint stock system transformation step speeds up and so on. Distributes from the area looked, take Zhujiang Delta and Yangtze River delta as central southeast coastal area development quickly to mid-west area, south development quickly to north. At present develops quickest, the mold produces the most centralized province is Guangdong and Zhejiang, places such as Jiangsu, Shanghai, Anhui and Shandong also has a bigger development in recent years .Although our country mold total quantity had at present achieved the suitable scale, the mold level also has the very big enhancement, after but design manufacture horizontal overall rise and fall industry developed country and so on Yu De, America, date, France, Italy many. The current existence question and the disparity mainly display in following several aspects:(1) the total quantity falls short of demanddomestic mold assembling oneself rate only ,about 70%. Low-grade mold , center upscale mold assembling oneself rate only has 50% about .(2) the enterprise organizational structure, the product structure, the technical structure and the import and export structure does not gatherin our country mold production factory to be most is from the labor mold workshop which produces assembles oneself (branch factory), from produces assembles oneself the proportion to reach as high as about 60%, but the overseas mold ultra 70% is the commodity mold. The specialized mold factory mostly is "large and complete", "small and entire" organization form, but overseas mostly is "small but", "is specially small and fine". Domestic large-scale, precise, complex, the long life mold accounts for the total quantity proportion to be insufficient 30%, butoverseas in 50% above 2004 years, ratio of the mold import and export is 3.7:1, the import and export balances the after net import volume to amount to 1.32 billion US dollars, is world mold net import quantity biggest country .(3) the mold product level greatly is lower than the international standardthe production cycle actually is higher than the international water broad product level low mainly to display in the mold precision, cavity aspect and so on surface roughness, life and structure .(4) develops the ability badly, economic efficiency unsatisfactory our country mold enterprise technical personnel proportion low the level is lower, also does not take the product development, frequently is in the passive position in the market. Our country each mold staff average year creation output value approximately ,ten thousand US dollars, overseas mold industry developed country mostly 15 to10,000 US dollars, some reach as high as 25 to10,000 US dollars, relative is our country quite part of molds enterprises also continues to use the workshop type management with it, truly realizes the enterprise which the modernized enterprise manages fewTo create the above disparity the reason to be very many, the mold long-term has not obtained the value besides the history in as the product which should have, as well as the most state-owned enterprises mechanism cannot adapt the market economy, but also has the following several reasons: .(1) country to mold industry policy support dynamics also insufficientlyalthough the country already was clear about has promulgated the mold profession industrial policy, but necessary policy few, carried out dynamics to be weak. At present enjoyed the mold product increment duty enterprise nation 185, the majority enterprise still the tax burden is only overweight. The mold enterprise carries on the technologicaltransformations introduction equipment to have to pay the considerable amount the tax money, affects the technology advancement, moreover privately operated enterprise loan extremely difficult .(2) talented person serious insufficient, the scientific research development and the technical attack investment too urine mold profession is the technology, the fund, the work crowded industry, along with the time progress and the technical development, grasps the talented person which and skilled utilizes the new technology exceptionally short, the high-quality mold fitter and the enterprise management talent extremely is also anxious. Because the mold enterprise benefit unsatisfactory and takes insufficiently the scientific research development and the technical attack, the scientific research unit and the universities, colleges and institutes eye stares at is creating income, causes the mold profession invests too few in the scientific research development and the technical attack aspect, causes the mold technological development step not to be big, progresses not quick .(3) the craft equipment level to be low, also necessary is not good, the use factor lowrecent years our country engine bed profession progressed quickly, has been able to provide the quite complete precision work equipment, but compared with the overseas equipment, still had a bigger disparity. Although the domestic many enterprises have introduced many overseas advanced equipment, but the overall equipment level low are very more than the overseas many enterprises. As a result of aspect the and so on system and fund reason, introduces the equipment not not necessary, the equipment and the appendix not necessary phenomenon are extremely common, the equipment utilization rate low question cannot obtain the comparatively properly solution for a long time .(4) specialization, standardization, commercialized degree low, the cooperation abilitybecause receives "large and complete" "small and entire" the influence since long ago, mold specialization level low, the specialized labor division is not careful, the commercialized degree is low. At present domestic every year produces mold, commodity mold minister 40% About, other for from produce uses for oneself. Between the mold enterprise cooperates impeded, completes the comparatively large-scale mold complete task with difficulty. Mold standardization level low, mold standard letter use cave rare is low also to the mold quality, the cost has a more tremendous influence, specially has very tremendous influence .(5) to the mold manufacture cycle) the mold material and the mold correlation technology fallsthe mold material performance, the quality and the variety question often can affect the mold quality, the life and the cost, the domestically produced molding tool steel and overseas imports the steel products to compare has a bigger disparity. Plastic, plate, equipment energy balance, also direct influence mold level enhancement .At present, our country economy still was at the high speed development phase, on the international economical globalization development tendency is day by day obvious, this has provided the good condition and the opportunity for the our country mold industry high speed development. On the one hand, the domestic mold market will continue high speed to develop, on the other hand, the mold manufacture also gradually will shift as well as the transnational group to our country carries on the mold purchase trend to our country extremely to be also obvious. Therefore, will take a broad view the future, international, the domestic mold market overall development tendency prospect will favor, estimated the Chinese mold will obtain the high speed development under the good market environment, our country not only can become the mold great nation, moreover certainly gradually will make the powerful nation to the mold the ranks to make great strides forward. "15" period, the Chinese mold industry level not only has the very big enhancement in the quantity andthe archery target aspect, moreover the profession structure, the product level, the development innovation ability, enterprise's system and the mechanism as well as the technology advancement aspect also can obtain a bigger development .The mold technology has gathered the machinery, the electron, chemistry, optics, the material, the computer, the precise monitor and the information network and so on many disciplines, is a comprehensive nature multi-disciplinary systems engineering. The mold technology development tendency mainly is the mold product to larger-scale, preciser, more complex and a more economical direction develops, the mold product technical content unceasingly enhances, the mold manufacture cycle unceasingly reduces, the mold production faces the information, is not having the chart, is fine, the automated direction develops, the mold enterprise to the technical integration, the equipment excellent, is producing approves the brand, the management information, the management internationalization direction develops. Our country mold profession still will have to enhance from now on the general character technology had :(1) to establish in the CAD/CAE platform the advanced mold design technology, enhances modernization which the mold designed, information, intellectualization, standardized level .(2) establishes in the CAM/CAPP foundation the advanced mold processing technology and the advanced manufacture technology unifies, raises the automated level and the production efficiency which the mold processes .(3) the mold production enterprise's information management technology. For example PDM (product data management), ERP (enterprise resource management), MIS (mold manufacture management information system) and information network technology the and so on INTERMET platform application, the promotion and the development .(4) are high speed, Gao Jing, the compound mold processing technology research and the application. For example the ultra fine ramming mold manufacture technology, the precise plastic and the compression casting mold manufacture technology and so on .(5) enhances the mold production efficiency, reduces the cost and reduces the mold production cycle each kind of fast economical mold manufacture technology .(6) the advanced manufacture technology application. For example hot technology and so on flow channel technology, gas auxiliary technology, hypothesized technology, nanotechnology, rapid scanning technology, reversion project, parallel project in the mold research, the development, the processing process application .(7) the raw material the simulation technology which forms in the mold .(8) the advanced mold processing and the appropriation equipment research and the development .(9) the mold and the mold standard letter, the important auxiliary standardized technology .(10) the mold and its the product examination technology.(11) high quality, the new mold material research and the development and its the correct application .(12) the mold production enterprise's modern management technology □Mold profession in "十15" period needs to solve the key essential technology should be the mold information, the digitized technology and precise, ultra fine, high speed, the highly effective manufacture technology aspect breakthroughAlong with the national economy total quantity and the industry product technology unceasing development, all the various trades and occupations to the mold demand quantity more and more big, the specification more and more is also high.Although mold type many, but its development should be with emphasis both can meet the massive needs, and has the comparatively high-tech content, specially at present domestic still could not be self-sufficient, needs the massive imports the mold and can represent the development direction large-scale, precise, is complex, the long life mold. The mold standard letter type, the quantity, the level, the production a and so on have the significant influence to the entire mold profession development. Therefore, some important mold standard letters also must the prioritize, moreover its development speed should quickly to the mold development speed, like this be able unceasingly to raise our country mold standardization level, thus improves the mold quality, reduces the mold production cycle, reduces the cost. Because our country mold product holds the bigger price superiority in the international market, therefore regarding the exportation prospect good mold product also should take key develops. According to the above required quantity big, the technical content is high, represents the development direction, the export prospect good principle choice prioritize product, moreover chooses the product to have at present to have the certain technology base, belongs has the condition, has the product which the possibility develops .According to "十15" the mold profession development plan, "十15" the period mold product development mainly has following several kind of the automobile cover mold(1) ramming mold to occupythe mold total quantity dish with emphasis above 40%. Automobile cover mold mainly for automobile necessary, also includes for the agriculture with the vehicle, the project machinery and the farm machinery necessary cover mold, it has the very big representation in the ramming mold, the mold mostly is large and middle scale, structure complex, the specification is high. For the passenger vehicle necessary cover mold, the request is in particular higher, may represent the ramming mold the level. This kind of mold our country had the certain technology base,already for middle-grade passenger vehicle necessary, but the level is not high, the ability is insufficient, at present satisfying rate only has one about the half. Center the upscale passenger vehicle cover mold main dependence import, has become the bottleneck which the automobile develops, enormous influence vehicle type development .(2)the precise ramming moldmulti- locations level was entering the mold and fine represents the ramming mold development direction, the precision request life request has been extremely high, mainly for the electronics industry, the automobile, the instrument measuring appliance, the electrical machinery electric appliance and so on formed a complete set. These two kind of molds, domestic had the suitable foundation, and has introduced the overseas technology and the equipment, the individual enterprise produces the product has achieved the world level, but the majority of enterprises still had a bigger disparity, the supply total quantity insufficient, the import were very many(3) the large-scale precise plastic moldplastic mold accounts for the mold total quantity 10%, moreover this proportion also is rising. In the plastic mold necessary large-scale casts the mold for the automobile and the electrical appliances, necessary models for the integrated circuit seals the mold, for the electronic information industry and the machinery and the packing necessary multilayer, the multi- cavities, the multi- material qualities, the multicolor precise note , and saves water the agricultural necessary plastic different molding for the new building materials to squeeze out the mold and the pipeline and the nozzle mold and so on, at present although had the suitable technology base and fast is developing, but the technical level and overseas still had a bigger disparity, the total quantity falls short of demand, Every year import amount reaches several hundred million US dollar.(4) the main mold standard to imitateeat present domestically to have an greater output the mold standard letter mainly is the mold frame, the guidance, the throwout lever pushes the tube, the elastic part and so on. These products not only the domestic necessary massive need, the exportation prospect very is also good, should continue vigorously to develop. The nitrogen cylinder and the hot flow channel part main dependence import, should raise the level in the existing foundation, forms the standard and organization scale production.(5) the other high-tech content moldsoccupiesin the mold total quantity green 8% compression casting mold, large-scale thin wall precise compression casting technology content high, the difficulty is big. The magnesium alloy compression casting mold at present although just started, but the prospects for development were good, have the representation. The meridian rubber tire mold also is the development direction, detachable mold technology difficulty is biggest. With fast takes shape some fast pattern making technologies and the corresponding fast economical mold which the technology unifies has the very good prospects for development. These high-tech content molds in "十15" period also should the prioritize .模具设计与制造模具是制造业的重要工艺基础,在我国,模具制造属于专用设备制造业。

塑料注塑模具论文中英文对照资料外文翻译文献

塑料注塑模具论文中英文对照资料外文翻译文献

外文资料翻译及原文【原文一】CONCURRENT DESIGN OF PLASTICS INJECTION MOULDS AbstractThe plastic product manufacturing industry has been growing rapidly in recent years. One of the most popular processes for making plastic parts is injection moulding. The design of injection mould is critically important to product quality and efficient product processing.Mould-making companies, who wish to maintain the competitive edge, desire to shorten both design and manufacturing leading times of the by applying a systematic mould design process. The mould industry is an important support industry during the product development process, serving as an important link between the product designer and manufacturer. Product development has changed from the traditional serial process of design, followed by manufacture, to a more organized concurrent process where design and manufacture are considered at a very early stage of design. The concept of concurrent engineering (CE) is no longer new and yet it is still applicable an d relevant in today’s manuf acturing environment. Team working spirit, management involvement, total design process and integration of IT tools are still the essence of CE. The application of The CE process to the design of an injection process involves the simultaneous consideration of plastic part design, mould design and injection moulding machineselection, production scheduling and cost as early as possible in the design stage.This paper presents the basic structure of an injection mould design. The basis of this system arises from an analysis of the injection mould design process for mould design companies. This injection mould design system covers both the mould design process and mould knowledge management. Finally the principle of concurrent engineering process is outlined and then its principle is applied to the design of a plastic injection mould.Keywords :Plastic injection mould design, Concurrent engineering, Computer aided engineering, Moulding conditions, Plastic injection moulding, Flow simulation1.IntroductionInjection moulds are always expensive to make, unfortunately without a mould it can not be possible ho have a moulded product. Every mould maker has his/her own approach to design a mould and there are many different ways of designing and building a mould. Surely one of the most critical parameters to be considered in the design stage of the mould is the number of cavities, methods of injection, types of runners, methods of gating, methods of ejection, capacity and features of the injection moulding machines. Mould cost, mould quality and cost of mould product are inseparableIn today’s completive environment, computer aided mould filling simulation packages can accurately predict the fill patterns of any part. This allows for quick simulations of gate placements and helps finding the optimal location. Engineers can perform moulding trials on the computer before the part design is completed. Process engineers can systematically predict a design and process window, and can obtain information about the cumulative effect of the process variables that influence part performance, cost, and appearance.2.Injection MouldingInjection moulding is one of the most effective ways to bring out the best in plastics. It is universally used to make complex, finished parts, often in a single step, economically, precisely and with little waste. Mass production of plastic parts mostly utilizes moulds. Themanufacturing process and involving moulds must be designed after passing through the appearance evaluation and the structure optimization of the product design. Designers face a huge number of options when they create injection-moulded components. Concurrent engineering requires an engineer to consider the manufacturing process of the designed product in the development phase. A good design of the product is unable to go to the market if its manufacturing process is impossible or too expensive. Integration of process simulation, rapid prototyping and manufacturing can reduce the risk associated with moving from CAD to CAM and further enhance the validity of the product development.3. Importance of Computer Aided Injection Mould DesignThe injection moulding design task can be highly complex. Computer Aided Engineering (CAE) analysis tools provide enormous advantages of enabling design engineers to consider virtually and part, mould and injection parameters without the real use of any manufacturing and time. The possibility of trying alternative designs or concepts on the computer screen gives the engineers the opportunity to eliminate potential problems before beginning the real production. Moreover, in virtual environment, designers can quickly and easily asses the sensitivity of specific moulding parameters on the quality and manufacturability of the final product. All theseCAE tools enable all these analysis to be completed in a meter of days or even hours, rather than weeks or months needed for the real experimental trial and error cycles. As CAE is used in the early design of part, mould and moulding parameters, the cost savings are substantial not only because of best functioning part and time savings but also the shortens the time needed to launch the product to the market.The need to meet set tolerances of plastic part ties in to all aspects of the moulding process, including part size and shape, resin chemical structure, the fillers used, mould cavity layout, gating, mould cooling and the release mechanisms used. Given this complexity, designers often use computer design tools, such as finite element analysis (FEA) and mould filling analysis (MFA), to reduce development time and cost. FEA determines strain, stress and deflection in a part by dividing the structure into small elements where these parameters can be well defined. MFA evaluates gate position and size to optimize resin flow. It also defines placement of weld lines, areas of excessive stress, and how wall and rib thickness affect flow. Other finite element designtools include mould cooling analysis for temperature distribution, and cycle time and shrinkage analysis for dimensional control and prediction of frozen stress and warpage.The CAE analysis of compression moulded parts is shown in Figure 1. The analysis cycle starts with the creation of a CAD model and a finite element mesh of the mould cavity. After the injection conditions are specified, mould filling, fiber orientation, curing and thermal history, shrinkage and warpage can be simulated. The material properties calculated by the simulation can be used to model the structural behaviour of the part. If required, part design, gate location and processing conditions can be modified in the computer until an acceptable part is obtained. After the analysis is finished an optimized part can be produced with reduced weldline (known also knitline), optimized strength, controlled temperatures and curing, minimized shrinkage and warpage.Machining of the moulds was formerly done manually, with a toolmaker checking each cut. This process became more automated with the growth and widespread use of computer numerically controlled or CNC machining centres. Setup time has also been significantly reduced through the use of special software capable of generating cutter paths directly from a CAD data file. Spindle speeds as high as 100,000 rpm provide further advances in high speed machining. Cutting materials have demonstrated phenomenal performance without the use of any cutting/coolant fluid whatsoever. As a result, the process of machining complex cores and cavities has been accelerated. It is good news that the time it takes to generate a mould is constantly being reduced. The bad news, on the other hand, is that even with all these advances, designing and manufacturing of the mould can still take a long time and can be extremely expensive.Figure 1 CAE analysis of injection moulded partsMany company executives now realize how vital it is to deploy new products to market rapidly. New products are the key to corporate prosperity. They drive corporate revenues, market shares, bottom lines and share prices. A company able to launch good quality products with reasonable prices ahead of their competition not only realizes 100% of the market before rival products arrive but also tends to maintain a dominant position for a few years even after competitive products have finally been announced (Smith, 1991). For most products, these two advantages are dramatic. Rapid product development is now a key aspect of competitive success. Figure 2 shows that only 3–7% of the product mix from the average industrial or electronics company is less than 5 years old. For companies in the top quartile, the number increases to 15–25%. For world-class firms, it is 60–80% (Thompson, 1996). The best companies continuously develop new products. At Hewlett-Packard, over 80% of the profits result from products less than 2 years old! (Neel, 1997)Figure 2. Importance of new product (Jacobs, 2000)With the advances in computer technology and artificial intelligence, efforts have been directed to reduce the cost and lead time in the design and manufacture of an injection mould. Injection mould design has been the main area of interest since it is a complex process involving several sub-designs related to various components of the mould, each requiring expert knowledge and experience. Lee et. al. (1997) proposed a systematic methodology and knowledge base for injection mould design in a concurrent engineering environment.4.Concurrent Engineering in Mould DesignConcurrent Engineering (CE) is a systematic approach to integrated product development process. It represents team values of co-operation, trust and sharing in such a manner that decision making is by consensus, involving all per spectives in parallel, from the very beginning of the productlife-cycle (Evans, 1998). Essentially, CE provides a collaborative, co-operative, collective and simultaneous engineering working environment. A concurrent engineering approach is based on five key elements:1. process2. multidisciplinary team3. integrated design model4. facility5. software infrastructureFigure 3 Methodologies in plastic injection mould design, a) Serial engineering b) Concurrent engineeringIn the plastics and mould industry, CE is very important due to the high cost tooling and long lead times. Typically, CE is utilized by manufacturing prototype tooling early in the design phase to analyze and adjust the design. Production tooling is manufactured as the final step. The manufacturing process and involving moulds must be designed after passing through the appearance evaluation and the structure optimization of the product design. CE requires an engineer to consider the manufacturing process of the designed product in the development phase.A good design of the product is unable to go to the market if its manufacturing process is impossible. Integration of process simulation and rapid prototyping and manufacturing can reduce the risk associated with moving from CAD to CAM and further enhance the validity of the product development.For years, designers have been restricted in what they can produce as they generally have todesign for manufacture (DFM) – that is, adjust their design intent to enable the component (or assembly) to be manufactured using a particular process or processes. In addition, if a mould is used to produce an item, there are therefore automatically inherent restrictions to the design imposed at the very beginning. Taking injection moulding as an example, in order to process a component successfully, at a minimum, the following design elements need to be taken into account:1. . geometry;. draft angles,. Non re-entrants shapes,. near constant wall thickness,. complexity,. split line location, and. surface finish,2. material choice;3. rationalisation of components (reducing assemblies);4. cost.In injection moulding, the manufacture of the mould to produce the injection-moulded components is usually the longest part of the product development process. When utilising rapid modelling, the CAD takes the longer time and therefore becomes the bottleneck.The process design and injection moulding of plastics involves rather complicated and time consuming activities including part design, mould design, injection moulding machine selection, production scheduling, tooling and cost estimation. Traditionally all these activities are done by part designers and mould making personnel in a sequential manner after completing injection moulded plastic part design. Obviously these sequential stages could lead to long product development time. However with the implementation of concurrent engineering process in the all parameters effecting product design, mould design, machine selection, production scheduling,tooling and processing cost are considered as early as possible in the design of the plastic part. When used effectively, CAE methods provide enormous cost and time savings for the part design and manufacturing. These tools allow engineers to virtually test how the part will be processed and how it performs during its normal operating life. The material supplier, designer, moulder and manufacturer should apply these tools concurrently early in the design stage of the plastic parts in order to exploit the cost benefit of CAE. CAE makes it possible to replace traditional, sequential decision-making procedures with a concurrent design process, in which all parties can interact and share information, Figure 3. For plastic injection moulding, CAE and related design data provide an integrated environment that facilitates concurrent engineering for the design and manufacture of the part and mould, as well as material selection and simulation of optimal process control parameters.Qualitative expense comparison associated with the part design changes is shown in Figure 4 , showing the fact that when design changes are done at an early stages on the computer screen, the cost associated with is an order of 10.000 times lower than that if the part is in production. These modifications in plastic parts could arise fr om mould modifications, such as gate location, thickness changes, production delays, quality costs, machine setup times, or design change in plastic parts.Figure 4 Cost of design changes during part product development cycle (Rios et.al, 2001)At the early design stage, part designers and moulders have to finalise part design based on their experiences with similar parts. However as the parts become more complex, it gets rather difficult to predict processing and part performance without the use of CAE tools. Thus for even relatively complex parts, the use of CAE tools to prevent the late and expensive design changesand problems that can arise during and after injection. For the successful implementation of concurrent engineering, there must be buy-in from everyone involved.5.Case StudyFigure 5 shows the initial CAD design of plastics part used for the sprinkler irrigation hydrant leg. One of the essential features of the part is that the part has to remain flat after injection; any warping during the injection causes operating problems.Another important feature the plastic part has to have is a high bending stiffness. A number of feeders in different orientation were added to the part as shown in Figure 5b. These feeders should be designed in a way that it has to contribute the weight of the part as minimum as possible.Before the design of the mould, the flow analysis of the plastic part was carried out with Moldflow software to enable the selection of the best gate location Figure 6a. The figure indicates that the best point for the gate location is the middle feeder at the centre of the part. As the distortion and warpage of the part after injection was vital from the functionality point of view and it has to be kept at a minimum level, the same software was also utilised to yiled the warpage analysis. Figure 5 b shows the results implying the fact that the warpage well after injection remains within the predefined dimensional tolerances.6. ConclusionsIn the plastic injection moulding, the CAD model of the plastic part obtained from commercial 3D programs could be used for the part performance and injection process analyses. With the aid ofCEA technology and the use of concurrent engineering methodology, not only the injection mould can be designed and manufactured in a very short of period of time with a minimised cost but also all potential problems which may arise from part design, mould design and processing parameters could be eliminated at the very beginning of the mould design. These two tools help part designers and mould makers to develop a good product with a better delivery and faster tooling with less time and money.References1. Smith P, Reinertsen D, The time-to-market race, In: Developing Products in Half the Time. New York, Van Nostrand Reinhold, pp. 3–13, 19912.Thompson J, The total product development organization. Proceedings of the SecondAsia–Pacific Rapid Product Development Conference, Brisbane, 19963.Neel R, Don’t stop after t he prototype, Seventh International Conference on Rapid Prototyping, San Francisco, 19974.Jacobs PF, “Chapter 3: Rapid Product Development” in Rapid Tooling: Technologies and Industrial Applications , Ed. Peter D. Hilton; Paul F. Jacobs, Marcel Decker, 20005.Lee R-S, Chen, Y-M, and Lee, C-Z, “Development of a concurrent mould design system: a knowledge based approach”, Computer Integrated Manufacturing Systems, 10(4), 287-307, 19976.Evans B., “Simultaneous Engineering”, Mechanical Engineering , Vol.110, No.2, pp.38-39, 19987.Rios A, Gramann, PJ and Davis B, “Computer Aided Engineering in Compression Molding”, Composites Fabricators Association Annual Conference , Tampa Bay, 2001【译文一】塑料注塑模具并行设计塑料制品制造业近年迅速成长。

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,。

注塑模具设计技术中英文对照外文翻译文献

注塑模具设计技术中英文对照外文翻译文献

中英文资料对照外文翻译英文:Design and Technology of the Injection Mold1、3D solid model to replace the center layer modelThe traditional injection molding simulation software based on products of the center layer model. The user must first be thin-walled plastic products abstract into approximate plane and curved surface, the surface is called the center layer. In the center layer to generate two-dimensional planar triangular meshes, the use of these two-dimensional triangular mesh finite element method, and the final result of the analysis in the surface display. Injection product model using3D solid model, the two models are inconsistent, two modeling inevitable. But because of injection molding product shape is complex and diverse, the myriads of changes from athree-dimensional entity, abstraction of the center layer is a very difficult job, extraction process is very cumbersome and time-consuming, so the design of simulation software have fear of difficulty, it has become widely used in injection molding simulation software the bottleneck.HSCAE3D is largely accepted3D solid / surface model of the STL file format. Now the mainstream CAD/CAM system, such as UG, Pro/ENGINEER, CATIA and SolidWorks, can output high quality STL format file. That is to say, the user can use any commercial CAD/CAE systems to generate the desired products3D geometric model of the STL format file, HSCAE3D can automatically add the STL file into a finite element mesh model, through the surface matching and introduction of a new boundary conditions to ensure coordination of corresponding surface flow, based on3D solid model of analysis, and display of three-dimensional analysis results, replacing the center layer simulation technology to abstract the center layer, and then generate mesh this complicated steps, broke through system simulation application bottlenecks, greatly reducing the burden of user modeling, reduces the technical requirement of the user, the user training time from the past few weeks shorter for a fewhours. Figure 1 is based on the central layer model and surface model based on 3D solid / flow analysis simulation comparison chart.2、Finite element, finite difference, the control volume methodsInjection molding products are thin products, products in the thickness direction of size is much smaller than the other two dimensions, temperature and other physical quantities in the thickness direction of the change is very large, if the use of a simple finite element and finite difference method will cause analysis time is too long, can not meet the actual needs of mold design and manufacturing. We in the flow plane by using finite element method, the thickness direction by using finite difference method, were established and plane flow and thickness directions corresponding to the size of the grid and coupling, while the accuracy is guaranteed under the premise of the calculation speed to meet the need of engineering application, and using the control volume method is solved. The moving boundary problem in. For internal and external correspondence surface differences between products, can be divided into two parts the volume, and respectively formed the control equation, the junction of interpolation to ensure thatthe two part harmony contrast.3、Numerical analysis and artificial intelligence technologyOptimization of injection molding process parameters has been overwhelming majority of mold design staff concerns, the traditional CAE software while in computer simulation of a designated under the conditions of the injection molding conditions, but is unable to automatically optimize the technical parameters. Using CAE software personnel must be set to different process conditions were multiple CAE analysis, combined with practical experience in the program were compared between, can get satisfactory process scheme. At the same time, the parts after the CAE analysis, the system will generate a large amount of information about the project ( product, process, analyzes the results ), which often results in a variety of data form, requiring the user to have the analysis and understanding of the results of CAE analysis ability, so the traditional CAE software is a kind of passive computational tools, can provide users with intuitionistic, effective engineering conclusion, to software users demand is too high, the influence of CAE system in the larger scope of application and popularization. In view of the above, HSCAE3D software in the original CAE system based on accurate calculationfunction, the knowledge engineering technology is introduced the system development, the use of artificial intelligence is the ability of thinking and reasoning, instead of the user to complete a large number of information analysis and processing work, directly provide guiding significance for the process of conclusions and recommendations, effectively solve the CAE of the complexity of the system and the requirements of the users of the contradiction between, shortening of the CAE system and the distance between the user, the simulation software by traditional " passive" computational tools to " active" optimization system. HSCAE3D system artificial intelligence technology will be applied to the initial design, the results of the analysis of CAE interpretation and evaluation, improvement and optimization analysis of3 aspects.译文:注塑模具设计的技术1.用三维实体模型取代中心层模型传统的注塑成形仿真软件基于制品的中心层模型。

模具设计外文翻译

模具设计外文翻译

外文资料翻译系别. 专业. 班级. 姓名. 学号. 指导教师.2011年4 月一、China’s mold industryDue to historical reasons for the formation of closed, "big and complete" enterprise features, most enterprises in China are equipped with mold workshop, in factory matching status since the late 70s have a mold the concept of industrialization and specialization of production. Production efficiency is not high, poor economic returns. Mold production industry is small and scattered, cross-industry, capital-intensive, professional, commercial and technical management level are relatively low.According to incomplete statistics, there are now specialized in manufacturing mold, the product supporting mold factory workshop (factory) near 17 000, about 600 000 employees, annual output value reached 20 billion yuan mold. However, the existing capacity of the mold and die industry can only meet the demand of 60%, still can not meet the needs of national economic development. At present, the domestic needs of large, sophisticated, complex and long life of the mold also rely mainly on imports. According to customs statistics, in 1997 630 million U.S. dollars worth of imports mold, not including the import of mold together with the equipment; in 1997 only 78 million U.S. dollars export mold. At present the technological level of China Die & Mould Industry and manufacturing capacity, China's national economy in the weak links and bottlenecks constraining sustainable economic development.1、Research on the Structure of industrial products moldIn accordance with the division of China Mould Industry Association, China mold is divided into 10 basic categories, which, stamping die and plastic molding two categories accounted for the main part. Calculated by output, present, China accounts for about 50% die stamping, plastic molding die about 20%, Wire Drawing Die (Tool) about 10% of the world's advanced industrial countries and regions, the proportion of plastic forming die die general of the total output value 40%.Most of our stamping die mold for the simple, single-process mode and meet the molds, precision die, precision multi-position progressive die is also one of the few, die less than 100 million times the average life of the mold reached 100 million times the maximum life of more than accuracy 3 ~ 5um, more than 50 progressive station, and the international life ofthe die 600 million times the highest average life of the die 50 million times compared to the mid 80s at the international advanced level.China's plastic molding mold design, production technology started relatively late, the overall level of low. Currently a single cavity, a simple mold cavity 70%, and still dominant.A sophisticated multi-cavity mold plastic injection mold, plastic injection mold has been able to multi-color preliminary design and manufacturing. Mould is about 80 million times the average life span is about, the main difference is the large deformation of mold components, excess burr side of a large, poor surface quality, erosion and corrosion serious mold cavity, the mold cavity exhaust poor and vulnerable such as, injection mold 5um accuracy has reached below the highest life expectancy has exceeded 20 million times, the number has more than 100 chamber cavity, reaching the mid 80s to early 90s the international advanced level.2、mold Present Status of TechnologyTechnical level of China's mold industry currently uneven, with wide disparities. Generally speaking, with the developed industrial countries, Hong Kong and Taiwan advanced level, there is a large gap.The use of CAD / CAM / CAE / CAPP and other technical design and manufacture molds, both wide application, or technical level, there is a big gap between both. In the application of CAD technology design molds, only about 10% of the mold used in the design of CAD, aside from drawing board still has a long way to go; in the application of CAE design and analysis of mold calculation, it was just started, most of the game is still in trial stages and animation; in the application of CAM technology manufacturing molds, first, the lack of advanced manufacturing equipment, and second, the existing process equipment (including the last 10 years the introduction of advanced equipment) or computer standard (IBM PC and compatibles, HP workstations, etc.) different, or because of differences in bytes, processing speed differences, differences in resistance to electromagnetic interference, networking is low, only about 5% of the mold manufacturing equipment of recent work in this task; in the application process planning CAPP technology, basically a blank state, based on the need for a lot of standardization work; in the mold common technology, such as mold rapid prototyping technology, polishing, electroforming technologies, surface treatment technologyaspects of CAD / CAM technology in China has just started. Computer-aided technology, software development, is still at low level, the accumulation of knowledge and experience required. Most of our mold factory, mold processing equipment shop old, long in the length of civilian service, accuracy, low efficiency, still use the ordinary forging, turning, milling, planing, drilling, grinding and processing equipment, mold, heat treatment is still in use salt bath, box-type furnace, operating with the experience of workers, poorly equipped, high energy consumption. Renewal of equipment is slow, technological innovation, technological progress is not much intensity. Although in recent years introduced many advanced mold processing equipment, but are too scattered, or not complete, only about 25% utilization, equipment, some of the advanced functions are not given full play.Lack of technology of high-quality mold design, manufacturing technology and skilled workers, especially the lack of knowledge and breadth, knowledge structure, high levels of compound talents. China's mold industry and technical personnel, only 8% of employees 12%, and the technical personnel and skilled workers and lower the overall skill level. Before 1980, practitioners of technical personnel and skilled workers, the aging of knowledge, knowledge structure can not meet the current needs; and staff employed after 80 years, expertise, experience lack of hands-on ability, not ease, do not want to learn technology. In recent years, the brain drain caused by personnel not only decrease the quantity and quality levels, and personnel structure of the emergence of new faults, lean, make mold design, manufacturing difficult to raise the technical level.mold industry supporting materials, standard parts of present conditionOver the past 10 years, especially the "Eighth Five-Year", the State organization of the ministries have repeatedly Material Research Institute, universities and steel enterprises, research and development of special series of die steel, molds and other mold-specific carbide special tools, auxiliary materials, and some promotion. However, due to the quality is not stable enough, the lack of the necessary test conditions and test data, specifications and varieties less, large molds and special mold steel and specifications are required for the gap. In the steel supply, settlement amount and sporadic users of mass-produced steel supply and demand contradiction, yet to be effectively addressed. In addition, in recent years have foreign steel mold set up sales outlets in China, but poor channels, technical services supportthe weak and prices are high, foreign exchange settlement system and other factors, promote the use of much current.Mold supporting materials and special techniques in recent years despite the popularization and application, but failed to mature production technology, most still also in the exploratory stage tests, such as die coating technology, surface treatment technology mold, mold guide lubrication technology Die sensing technology and lubrication technology, mold to stress technology, mold and other anti-fatigue and anti-corrosion technology productivity has not yet fully formed, towards commercialization. Some key, important technologies also lack the protection of intellectual property.China's mold standard parts production, the formation of the early 80s only small-scale production, standardization and standard mold parts using the coverage of about 20%, from the market can be assigned to, is just about 30 varieties, and limited to small and medium size. Standard punch, hot runner components and other supplies just the beginning, mold and parts production and supply channels for poor, poor accuracy and quality.3、Die & Mould Industry Structure in Industrial OrganizationChina's mold industry is relatively backward and still could not be called an independent industry. Mold manufacturer in China currently can be divided into four categories: professional mold factory, professional production outside for mold; products factory mold factory or workshop, in order to supply the product works as the main tasks needed to die; die-funded enterprises branch, the organizational model and professional mold factory is similar to small but the main; township mold business, and professional mold factory is similar. Of which the largest number of first-class, mold production accounts for about 70% of total output. China's mold industry, decentralized management system. There are 19 major industry sectors manufacture and use of mold, there is no unified management of the department. Only by China Die & Mould Industry Association, overall planning, focus on research, cross-sectoral, inter-departmental management difficulties are many.Mold is suitable for small and medium enterprises organize production, and our technical transformation investment tilted to large and medium enterprises, small and medium enterprise investment mold can not be guaranteed. Including product factory mold shop,factory, including, after the transformation can not quickly recover its investment, or debt-laden, affecting development.Although most products factory mold shop, factory technical force is strong, good equipment conditions, the production of mold levels higher, but equipment utilization rate.Price has long been China's mold inconsistent with their value, resulting in mold industry "own little economic benefit, social benefit big" phenomenon. "Dry as dry mold mold standard parts, standard parts dry as dry mold with pieces of production. Dry with parts manufactured products than with the mold" of the class of anomalies exist.二、Basic terminology1、ImpressionThe injection mould is an assenbly of parts containing within an inpression into which plastic material is injected and cooled. It is the impression which gives the moulding its form. The impression may, therefore, be defined as thatpart of the mould which imparts shape to the moulding.The impression is formed by two mould mimbers:(i)The cavity, which is the female portion of the mould, gices the moulding itsexternal form.(ii)The core, which is the male portion of the mould , forms the internal shape of the moulding.2、Cavity an core platesThe basic mould in this case consists of two plates. Into one plate is sunk the cavity which shapes the outside form of the moulding and os therefore known as the cavity plate. Similarly, the core which projects form the core plate forms the inside shape of the moulding os closed, the two plates come together forming a space between the cavity and core which is the impression.3、Sprue bushDuring the injection process plastic material is delivered to the mozzle of the machie as a melt;it is then tramsferred to the impression though a passage. The material in this passage is termed the sprue, and the bush is called a sprue bush.4、Runner and gate systemsThe material may bedirectly injected into the impression though the sprue bush or for moulds containing several impressions it may pass from the sprue bush hole through a runnerand gate system therefore entering the impression.5、Register ringIf the material is to pass without hidrance into the mould the mozzle and sprue must be correctly aligned. To endure that this is so the mould must be central to the machine and this can be achieved by including a regicter ring.6、Guide pillars and bushesTo mould an even-walled article it is necessary to ensure that the cavity and core are keptin alignmemt. This is done by incorporating guide pillars on one mould plate which then enter corresponding guide bushes in the other mould plate as the mouls closes.7、Fixed half and moving halfThe various mould parts fall naturally into two sections or halves. Hence, that half attached to the stationary platen of the machine (indicated by the chain dotted line)is termed the fixed half, The other half of the mould attached to the moving platen of the machine is known simply as the moving half. Now it has to be situsted. Generally the core is situated in the moving half and the overriding reason why this is so, is as follows:The moulding as it cools, will shrink on to the core and remain with it as the mould opens. This will occur irrespective of whether the core is in the fixed half or the moving half. However, this shrinkage on to the core means that some form of ejector system is almostly certainly necessary. Motivation for this ejector system iseasily provided if the core is in the moving half. Moreover, in the case of our single-impression basic mould, where a direct sprue feed to the underside of the moulding is desired the cavity must be in the fixed half and the core in the moving half.8、Methods of incorporating cavity and coreWe have now seen that in general the core is incorporsted in the moving half and the cavity in the fixed half. However, there are various methods by which the cavity and core can be incorporated in their respective halves of the mould. These represent two basic alternatives (i) the integer method where the cavity and core can be machined form steel plates which become part of the structural build-up of the mould, or (ii) the cavity and core can be machined form small blocks of steel, termed inderts, and subsequently bolstered. The choice between these alternatives constitutes an important decision on the part of the mould designer. The final result, nevertheless, will be the contains the core is termed the core plate and the plate or assembly which contains the cavity is termed the cavity plate.9、Cavity FabricationWhen a decision for making a mold is made, the cost is predicated on producing aspecified quantity of parts without additional tooling expenditure. Sometimes, the anticipatesare quantities are exceeded; other times, they all short of requirements, and costly repairs becomenecesary in order to supply the needs.In the making of cavities by machining, grinding, or electric discharge machining, there is constant drive to improve the rate of metal removal. Cutting tools as well as machine tools are developed for heavier and faster cuts; grinding wheels are tailor-made for special steels to allow deeper cuts per pass; and EDM machines are revamped to burn the metal at an accelerated pace.It is fully appreciated that faster mental-removal rate leads to more economical manufacture,but at the same time it mast be recognized that the newer cavity fabrication is associated with generation of more heat and indirectly with higher stresses that if not relieved can cause premature gailure.Suppliers of tool steel caution the user against fabricating stresses and strongly advise a stress-relieving operation. When a steel is to be heat-treated and a preheat cycle ia part of the heat-treating specification, then the metal-removal stresses will be eliminated.A great number of cavities are made of prehardened steel, and therefore would not be heat-treated.For those cavities,a stress-relieving operation should be carried out immediately after fabricaton.the stress-relieving temperature as a rule is about 100ºF below the tempring heat and is held for 30 min. for each inch of steel thickness. It is best to check the stress-relieving heat and time with the maker of the steel.The information about fabrication stress has always been emphasized by the steelmakers,but for some reason it has not been given the attention it deserves. Since a tool drawing should cover all the requirements of a tool element, it would be the appropriate place for a note such as the following:Note: For heat-treated steel:“Note: Use preheat and harden to RC ____.”Note: For prehardened steel:“Note: Stress relieve@___ºF for____hoursper____ inch of thickness.”Every effort should be made to eliminate the invisible source of problems, namely,fabricating stresses.Mold cavities can be produced by a variety of processes. The process to be used is Determined.First of all by the lowest cost at which the cavity can be produced for the desired end result. Other factors include precision of repairability. Frequently, a combination of processes is employed in order to meet all the specified requirements. The most common processes are discussed in the following sections.Specifically, investment casting may be considered for applications where the number of cavities is greater than six and tolerances of dimensions are in the range of ±0.005. It isparticularly adaptable to complex shapes and unusual configurations as well as for surface that are highly decorative and difficult to obtain by conventional processes. These decorative surface may have a wood grain, leather grain, or textured surface suitable for handle grips,etc.A lmost any alloy of steel or beryllium copper alloys can be cast to size and heat-treated metal hardness that is within the range of the alloy being cast. Acomparative cost evaluation will in many cases favor the investment process. The investment cast tooling when produced by qualified people can be of the same quality as those machined from bar stock., i.e.,they can be free of porosity, proper hardness, uniform with respect to each other, and where (and-where)the time element is a factor-can be produced in days instead of weeks. In this process, cavities have been made that weigh as much as 750 lb.The investment caqsting method calls for a model of a low-melt material such as wax, plastic, or frozen mercury. The model is a reproduction of the desired cavity block and, when cast, is ready for mounting in the base. It incorporates shrinkage allowances as well as a gating system for metal pouring. The complete model is sipped in a slurry of fine refractory material and then encased in the investment material, which may be plaster of paris or mixtures of ceramic materials with high refractory properties. With the encased investment fully set up, the model is removed from the mold by heating in can over to liquefy the meltable material and cause it to run out. The molten material is reclaimed for further use. The mold or investment casing is fully dried out during the heating. After these steps, the investment is preheated to 1000°to 2000ºF in preparation for the pouring of the metal. The preheat temperature is governed by the type of metal. When pouring is completed and solidification of the metal has taken place, the investment material is broken away to free the casting for removal of the gates and cleaning.The making of the model for cavity and core blocks of meltable material is an intermediate step. These model blocks are cast in molds that are the staring point for the process. The starting-point mold consists of the part cavity or core where the parting line width as well as block portin for mounting, etc., are built around the part cavity and core, and thus form the shape needed as the complete block.The investment-casting process was developed commercially to a high dehree of precision and quality during World War II for the manufacture of aviation gasturbine blades were made of alloys, which were difficult or impossible to be foged. Subsequently, refinements have been developed in the investment-casting process that are especially valuable to the moldmaking field. Most these improvements are in the area of investment materials for the pyrpose of maintaining closer tolerances on the castings. Some mold shops have equippedthemselves with the ability to produce investment castings alongside their regular fabrication facilities.三、Feed SystemIt is necessary to paovide a flow-way in the injection mould to connect the nozzle of the injection machine to each impression. This flow-way is termed the feed system. Normally the feed system comprises a sprue, runner and gate. These terms apply equally to the flow-way itself, and to the molded material which is removed from the flow-way itself in the process of extracting the molding.1、SprueA spure is a channel though which to transfer molten plastic injected from the nozzle of the injector the mold. It is a part of spure bush, which is a separate part from th mold.2、RunnerA runner is a channel that guides molten plastic into the cavity of a mold.3、GateA gate is an entrance through which molten plastic enters the cavity. The gate has the following functions:restricts the flow and the direction of molten plastic;simplifies cutting of a runner and moldings to simplify finishing of parts;quickly cools and solidifies to avoid backflow after molten plastic has filled up in the cavity.4、Cold slug wellThe purpose of the cold slug well, shown oppwsite the sprue, is theoretically to receive the material that has chilled at the front of the nozzle during the cooling and ejection phase. Perhaps of greater importance is the fact that it provides positive means whereby the sprue can be pulled from the sprue bush for ejection purposes.The sprue, the runner, and the gate will be discarded after a part is complete. However, the runner and the gate are important items that affect the quality or the cost of parts.四、Parting SurfaceThe parting surfaces of a mould are those portion of both mould plates, adjacent to the impressions, which butt together to form a seal and prevent the loss of plastic material from the impression. The parting surface is 1、classified flat and non-flatThe mature of the parting surface depends entirely on the shape of the component. A further consideration os that the parting surface must be chosen so that the molding can be removed from the mould. Many molding are required which have a parting line which lies ona non-planar or curved surface.When the parting surface os not flat, there is the quertion of unbalanced forces to consider in certain instances. The plastic material when under pressure within the impression, will exert a force which will tend to open the mould in the lateral direction. If this happens some flashing may occur on the angled face. The movement between the two mould halves will be resisted by the guide pillars, but even so, because of the large forced involved, it is desirable to balance the mould by reversing the step so that the parting surface continues across the mould as a mirror image of the section which includes the impression. It is often convenient to spercify an even number of impressions when considering this type of mould, as impressions positioned on opposite sides of the mould‟s centre-line serve to balance the mould.五、Mould coolingOne fundamental principle of injection molding os that hot material enters the mouls, where it cools rapidly to a temperature at which it solidified sufficiently to retain the shape of the impression. The temperature of the mould os therefore important as it governs a portion of the overall molding cycle. While the melt flows more freely in a hot mould, a greater cooling period is required before the solidified molding can be ejected. Alternatively, while the melt solidifies quickly in a cold mould it may not reach the extremities of the impression. A compromise between the two extremes must therefore be accepted to obtain the optimum molding cycle.The operating temperature for a particular mould will depend on a number of factors which include the following:type and grade of material to be molded;length of flow within the impression;wall section of the molding;length of the feed system, etc. It is often found advantageous to use a slightly higher temperature than is required just to fill the impression, as this tends to impreove the surface finish of the molding by minimizing weld lines, flow marks and other blemishes.To maintain the required temperature differential between the mould and plastic material, water or other fluid is circulated through holes or channels within the mould. These holes or channels are termed flow-ways or water-ways and the complete system of flow ways is termed the circuit.During the impression filling stage the hottert material will be in the vicinity of the entry point, i. e. the gate, the coolest material will be at the point farthest from the entry. The temperature of the coolant fluid, however, increases as it passes though the mould. Thereforeto achieve an even cooling rate over the molding surface it is necessary to locate the incoming coolant fluid adjacent to…hot‟molding surfaces and to locate the channels containing…heated‟coolant fluid adjacent to …cool‟molding surfaces. However, as will be seen from the following discussion, it is not always practicable to adopt the idealized appreach and the designer must use a fair amount of common sense when laying out coolant circuits if unnercessarily expensive moulds are to be avoided.Units for the circulation of water and other fluids are commercially available. These units are simply connected to the mould via flexible hoses, with these units the mould‟s temperature can be maintained within close limits. Close temperature control is not possible using the alternative system in which the mould is connected to a cold water supply.It is the mould designer‟s responsibility to provide an adequate circulating system within the mould. In general, the simplest systems are those in which holes are bored longitudinally through the mould plates. However, this is not necessarily the most dfficient method for a particular mould.When using drillings for the circulation of the coolant, however, these must not be positioned too close to the impression say closer than 16mm as this is likely to cause a marked temperature66variation across the impression, with resultant molding problems.The layout of a circuit is often complicated by the fact that flow ways must not be drilled too close to any other hole in the same mould plate. It will be recalled that the mould plate has a large number of holes or recessers, to accommodate ejector pins, guide pillars, guide bushes, sprue bush, inserts, etc. How close it is safe to position in a flow way adjacent to another hole depends to a large extent on the depth of the flow way driolling required. When drilling deep flow ways there is a tendency for the drill to wander off its prescribed course. A rule which is often applied is that for drillings up to 150mm deep the flow way should not be closer than 3 mm to any other hole. For deeper flow ways this allowance is increased to 5 mm.To obtain the best possible position for a circuit it is good practice to lay the circuit in at the earliest opportunity in the design. The other mould itens such as ejector pins, guide bushes, etc. , can then be positioned accordingly.六、Designs CAD/CAMAlthough CAD/CAM manufactures and suppliers are addressing the challenges mold disigners face when using software, these designers are still grappling with a number of issues. Kevin Crystal, senior quality engineer with The Protomold Co. (Maple Plain, MN)-a rapid injection molding company-reports that the greatest challenges he faces are with file。

模具设计与制造外文翻译

模具设计与制造外文翻译

附录1 英文原文Mould Design and ManufacturingCAD and CAM are widely applied in mould design and mould making.CAD allows you to draw a model on screen ,then view it from every angle using 3-D animating and ,finally ,to test it by introducing various parameters into the digital simulation models (pressure ,temperature ,impact ,etc .)CAM ,on the other hand ,allows you to control the manufacturing quality .The advantages of these computer technologies are legion ;shorter design times (modifications can be made at the speed of the computer ).lower cost ,faster manufacturing ,etc .This new approach also allows shorter production runs ,and to make last-minute changes to the mould for a particular part.Finally ,also ,these new processes can be use to make complex parts .Computer-Aided Design (CAD) of MouldTraditionally, the creation of drawings of mould tools has been a time-consuming task that is not part of the creative process. Drawings are an organizational necessity rather than a desired part of the process .Computer-Aided Design (CAD) means using the computer and peripheral devices to simplify and enhance the design process .CAD systems offer an efficient means of design ,and can be use to create inspection equipment .CAD data also can play a critical role in selecting process sequence .A CAD system consists of three basic components ;hardware ,software,User ,The hardware components of a typical CAD system include a processor ,a system display,a keyboard, a digitizer, and a plotter. The software component of a CAD system consists of the programs which allow it to perform design and drafting functions.The user is the tool designer who uses the hardware and software to perform the design process.Based on he 3-D data of the product, the core and cavity have to be designedsrally the designer begins with a preliminary part design ,which means the work around the core and cavity could change .Modern CAD systems can support this with calculating a spot line for a defined draft direction ,splitting the part in the core and cavity side and generating the run-off or shut-off true faces .After the calculation of the optimal draft of the part, the position and direction of the cavity, slides and inserts have to be defined .Then,in the conceptual stage, the positions and the geometry of the mould –such as slides, ejection system, etc. –are roughly defined. With this information, the size and thickness of the plates can be defined and the corresponding standard mould that comes nearest to the requirements is chosen and changed accordingly –by adjusting the constraints and paramenter so that any number of plates with any size can be use in the mould. Detailing the functional components and adding the standard any size can be used in the mould. Detailing the functional compontnts and adding the standard components complete the mould.This all happens in 3D .Moreover ,the mould system provide functions for the checking, modifying and detailing of the part .Already in this early stage ,drawings and bill of materials can be created automatically.Through the use of 3D and the intelligence of the mould system, typical 2D mistakes –such as a collision between cooling and components/cavities or the wrong position of a hole –can be eliminated at the beginning. At any stage a bill of materials and drawings can be created-allowing the material to be ordered on time and always having an actual document to discuss with the customer or a bid for a mould base manufacturer .The use of a special 3D mould design system can shorten development cycles, improve mould quality ,enhance teamwork and free the designer from tedious routine work .The development cycles can be shortened only when organization and personnel measures are taken. The part design, mould design, electric design and mould manufacturing departments have to consistently work together in a tight relationship .Computer-Aided Manufacturing (CAM ) of MouldOne way to reduce the cost of manufacturing and reduce lead-time is by settingup a manufacturing system that uses equipment and personnel to their fullest potential .the foundation for this type of manufacturing system as the use of CAD data to help in madding key process decisions that ultimately improve machining precision and reduce non-productive time .This is called as computer-aided manufacturing (CAM).The objective of CAM is to produce, if possible ,sections of a mould without intermediate steps by initiating machining operations from the computer workstation .With a good CAM system, automation does not just occur within individual features. Atuomation of machining processes also occurs between all of the features make up a part, resulting in tool-path optimization. As you create features, the CAM system constructs a process plan for you .Operations are ordered based on a system analysis to reduce tool changes and the number of tools used .On the CAM sidethe trend is toward newer technologies and processes such as micro milling to support the manufacturing of high-precision injection moulds with complex 3D structures and high surface qualities. CAM software will continue to add to the depth and breadth of the machining intelligence inherent in the software until the CNC programming process becomes completely automatic. This is especially true for advanced multifunction machine tools becomes completely automatic This is especially true for advanced multifunction machine tools that require a more flexible combination of machining operations .CAM software will continue to automate more and more of manufacturing redundant work that can be handled faster and more accratrly by computers, while retaining the control that machinists need.With the emphasis in the mould making industry today on producing moulds in the most efficient manner while still maintaining quality, mold makers need to keep up with the latest software technologies-packages that will allow them to program and cut complex moulds quickly so that mould production time can be reduced .In a nutshell, the industry is moving toward improving the quality of data exchange between CAD and CAM as well as CAM to the CNC ,and CAM software is becoming more “intelligent” as it relates to machining processes-resulting in reduction in both cycle time and overall machining time .Five-axis machining also is emerging as a “must-have” on the shop floor-especially when dealing with deepcavities. And with the introduction of electronic date processing (EDP) into the mould making industry, new opportunities have arisen in mould-making to shorten production time, improve cost efficiencies and achieve higher quality.The Science of mold MakingThe traditional method of making large automotive sheet metal dies by model building and tracing has been replaced by CAD/CAM terminals that convert mathematical descriptions of body panel shapes into cutter paths.Teledyne Specialty Equipment’s Efficient Die and Mold facility is one of the companies on the leading edge of this transformation.Only a few years ago,the huge steel dies requited for stamping sheet metal auto body panels were built by starting with a detailed blueprint and an accurate full-scale master model of the part. The model was the source from which the tooling was designed and produced.The dies,machined from castings,were prepared from patterns made by the die manutacturers or something supplied by the car maker.Secondary scale models called”tracing aids” were made from the master model for use on duplicating machines with tracers.These machines traced the contour of the scale model with a stylus,and the information derived guided a milling cutter that carved away unwanted metal to duplicate the shape of the model in the steel casting.All that is changing.Now,companies such as Teledyne Specialty Equipment’s Efficient Die and Mold operation in Independence,OH,work from CAD data supplied by customers to generate cutter paths for milling machines,which then automatically cut the sheetmetal dies and SMC compression molds.Although the process is used to make both surfaces of the tool, the draw die still requires a tryout and “benching” process.Also, the CAD data typically encompasses just the orimary surface of the tool,and some machined surfaces, such as the hosts and wear pads, are typically part of the math surface.William Nordby,vice president and business manager of dies and molds at Teledyne,says that “although no one has taken CAD/CAM to the point of building theentire tool,it will eventually go in that direction because the “big thrdd”want to compress cycle times and are trying to cut the amount of time that it takes to build the tooling.Tryout, because of the lack of development on the design end,is still a very time-consuming art, and very much a trial-and-error process.”No More Models and Tracing AidsThe results to this new technology are impressive. For example, tolerances are tighter and hand finishing of the primary die surface with grinders has all but been eliminated. The big difference, says Gary Kral, Teledyne’s director of engineering, is that the dimensional control has radically improved. Conventional methods of making plaster molds just couldn’t hold tolerances because of day-to-day temperature and humidity variations.”For SMC molds the process is so accurate , and because there is no spring back like there is when stamping sheet metal, tryouts are not always required.SMC molds are approved by customers on a regulate basis without ever running a part .Such approvals are possible because of Teledyne’s ability to check the tool surface based on mathematical analysis and guarantee that it is made exactly to the original design data. Because manual trials and processes have been eliminated, Teledyne has been able to consider foreign markets.” The ability to get a tool approved based on the mathe gives us the opportunity to compete in places we wouldn’t have otherwise,” says Nordby. According to Jim Church, systems manager at Teledyne, the company used to have lots of pattern makers ,and still has one model maker.”But 99.9 percent of the company’s work now is from CAD data. Instead of model makers, engineers work in front of computer monitors.”He says that improvements in tool quality and reduction in manufacturing time are significant. Capabilities of the process were demonstrated by producing two identical tools. One was cut using conventional patterns and tracing mills, and the other tool was machined using computer generated cutting paths. Although machining time was 14 percent greater with the CAM-generated path, polishing hours were cut by 33 percent. In all ,manufacturing time decreased 16.5 percent and tool quality increased 12 percent.Teledyne’s CAD/CAM system uses state-of-the-art software that allows engineers to design dies and molds, develop CNC milling cutter paths and incorporate design changes easily. The system supports full-color, shaded three-dimensional modeling on its monitors to enhance its design and analysis capabilities. The CAD/CAM system also provides finite element analysis that can be used to improve the quality of castings , and to analyze the thermal properties of molds. Inputs virtually from any customer database can be used either directly or through translation.CMM Is CriticalTeledyne’s coordinate measuring machine(CMM),says’Church,”is what has made a difference in terms of being able to move from the traditional manual processes of mold and die making to the automated system that Teledyne uses today.”The CMM precisely locates any point in a volume of space measuring 128 in, by 80 in, by 54 in, to an accuracy of 0.0007 in. It can measure parts, dies and molds weighing up to 40 tons. For maximum accuracy,the machine is housed in an environmentally isolated room where temperature is maintained within 2 deg.F of optimum. To isolate the CMM from vibration, it is mounted on a 100-ton concrete block supported on art cushions.According to Nordby, the CMM is used not only as a quality tool, but also as a process checking tool. “ As a tool goes through the shop, it is checked several times to validate the previous operation that was performed.”For example, after the initial surface of a mold is machined and before any finish work is done, it is run through the CMM for a complete data check to determine how close the surface is to the required geometry.The mold is checked with a very dense pattern based on flow lines of the part. Each mold is checked twice, once before benching and again after benching. Measurements taken from both halves of the mold are used to calculate theoretical stock thickness at full closure of the mold to verify its accuracy with the CAD design data.Sheet Metal Dies Are Different“Sheet metal is a different ballgame,” says Nordby, “because you have the issue of material springback and the way the metal forms in the die. What happens in the sheet metal is that you do the same kinds of things for the male punch as you would with SMC molds and you ensure that it is 100 percent to math data. But due to machined surface tolerance variations, the female half becomes the working side of the tool. And there is still a lot of development required after the tool goes into the press. The math generated surfaces apply primarily to the part surface of the tool.”EMS Tracks the Manufacturing ProcessTeledyne’s business operations also are computerized and carried over a network consisting of a V AX server and PC terminals. IMS (Effective Management Systems) software tracks orders, jobs in progress, location of arts, purchasing, receiving, and is now being upgraded to include accounting functions.Overall capabilities of the EMS system include bill-of-material planning and control, inventory management, standard costing, material history, master production scheduling, material requirements planning, customer order processing, booking and sales history, accounts receivable, labor history, shop floor control, scheduling, estimating, standard routings, capacity requirements planning, job costing, purchasing and receiving, requisitions, purchasing and receiving, requisitions, purchasing history and accounts payable.According to Frank Zugaro, Teledyne’s scheduling manager, the EMS software was chosen because of its capabilities in scheduling time and resources in a job shop environment. All information about a job is entered into inventory management to generate a structured bill of material. Then routes are attached to it and work orders are generated.The system provides daily updates of data by operator hour as well as a material log by shop order and word order. Since the database is interactive, tracking of materials received and their flow through the build procedure can be documented and cost data sent to accounting and purchasing.Gary Kral, Teledyne’s director of engineering, says that EMS is really a tracking device, and one of the systems greatest benefits is that it provides a documentedrecord of everything involving a job and eliminates problems that could arise from verbal instructions and promises. Kral says that as the system is used more, they are finding that it pays to document more things to make it part of the permanent record. It helps keep them focused.2 中文翻译模具设计与制造CAD和CAM广泛用于模具的设计和制造中。

铸造模具外文文献翻译、中英文翻译

铸造模具外文文献翻译、中英文翻译

外文资料翻译资料来源:《模具设计与制造专业英语》文章名:Chapter 3 Casting Dies书刊名:《English for Die & Mould Design and Manufacturing》作者:刘建雄王家惠廖丕博主编出版社:北京大学出版社,2002章节:Chapter 3 Casting Dies页码:P51~P60文章译名:铸造模具Chapter 3 Casting Dies3.1CastingThe first castings were made during the period 4000~3000 B.C., using stone and metal molds for casting copper. Various casting processes have been developed over a long period of time, each with its own characteristics and applications, to meet specific engineering and service requirements. Many parts and components are made by casting, including cameras, carburetors, engine blocks, crankshafts, automotive components, agricultural and railroad equipment, pipes and plumbing fixtures, power tools, gun barrels, frying pans, and very large components for hydraulic turbines.Casting can be done in several ways. The two major ones are sand casting, in which the molds used are disposable after each cycle, and die casting, or permanent molding, in which the same metallic die is used thousands or even millions of times. Both types of molds have three common features. They both have a “plumbing” system to channel molten alloy into the mold cavity. These channels are called sprues, runners, and gates (Fig. 3-1). Molds may be modified by cores which form holes and undercuts or inserts that become an integral part of the casting. Inserts strengthen and reduce friction, and they may be more machinable than the surrounding metal. For example, a steel shaft when properly inserted into a die cavity results in an assembled aluminum step gear after the shot.After pouring or injection, the resulting castings require subsequent operations such trim-ming, inspection, grinding, and repairs to a greater or lesser extent prior to shipping. Premium-quality castings from alloys of aluminum or steel require x-ray soundness that will be acceptable by the customer.Certain special casting processes are precision-investment casting, low-pressure casting, and centrifugal casting.3.2Sand CastingThe traditional method of casting metals is in sand molds and has been used for millennia. Simply stated, sand casting consists of (a) placing a pattern having the shape of the desired casting in sand to make an imprint, (b) incorporating a gating system, (c) filling the resulting cavity with molten metal, (d) allowing the metal to cool until it solidifies, (e) breaking away the sand mold, and (f) removing the casting (Fig. 3-2). The production steps for a typical sand-casting operation are shown in Fig. 3-3.Although the origins of sand casting date to ancient times, it is still the most prevalent form of casting. In the United States alone, about 15 million tons of metal are cast by this method each year.Open riser Vent Pouring basin (cup)CopeBlind FlaskriserSprueCore(sand)SandParting lineDragMoldcavityChokeRunner GateSandFig. 3-2 Schematic illustration of a sand mold33.2.1SandsMost sand casting operations use silica sand (SiO2), which is the product of the dis- integration of rocks over extremely long periods of time. Sand is inexpensive and is suitable as mold material because of its resistance to high temperatures. There are two general types of sand: naturally bonded (bank sand) and synthetic (lake sand). Because its composition can be controlled more accurately, synthetic sand is preferred by most foundries.Several factors are important in the selection of sand for molds. Sand having fine, round grains can be closely packed and forms a smooth mold surface. Although fine-grained sand enhances mold strength, the fine grains also lower mold permeability. Good permeability of molds and cores allows gases and steam evolved during casting to escape easily.3.2.2Types of Sand MoldsSand molds are characterized by the types of sand that comprise them and by the methods used to produce them. There are three basic types of sand molds: greensand, cold-box, and no-bake molds.The most common mold material is green molding sand, which is a mixture of sand, clay, and water. The term “green” refers to the fact that the sand in the mold is moist or damp while the metal is being poured into it. Greensand molding is the least expensive method of makingmolds.In the skin-dried method, the mold surfaces are dried, either by storing the mold in air or by drying it with torches. These molds are generally used for large castings because of their higher strength.Sand molds are also oven dried (baked) prior to pouring the molten metal; they are stronger than greensand molds and impart better dimensional accuracy and surface finish to the casting. However, this method has drawbacks: distortion of the mold is greater; the castings are more susceptible to hot tearing because of the lower collapsibility of the mold; and the production rate is slower because of the drying time required.In the cold-box mold process, various organic and inorganic binders are blended into the sand to bond the grains chemically for greater strength. These molds are dimensionally more accurate than greensand molds but are more expensive.In the no-bake mold process, a synthetic liquid resin is mixed with the sand; the mixture hardens at room temperature. Because bonding of the mold in this and in thecold-box process takes place without heat, they are called cold-setting processes.The following are the major components of sand molds (Fig. 3-2):(1)The mold itself, which is supported by a flask. Two-piece molds consist of a cope on top and a drag on the bottom. The seam between them is the parting line. When more than two pieces are used, the additional parts are called cheeks.(2)A pouring basin or pouring cup, into which the molten metal is poured.(3)A sprue, through which the molten metal flows downward.(4)The runner system, which has channels that carry the molten metal from the sprue to the mold cavity. Gates are the inlets into the mold cavity.(5)Risers, which supply additional metal to the casting as it shrinks during solidification. Fig. 3-2 shows two different types of risers: a blind riser and an open riser.(6)Cores, which are inserts made from sand. They are placed in the mold to form hollow regions or otherwise define the interior surface of the casting. Cores are also used on the outside of the casting to form features such as lettering on the surface of a casting or deep external pockets.(7)Vents, which are placed in molds to carry off gases produced when the molten metal comes into contact with the sand in the mold and core. They also exhaust air from the mold cavity as the molten metal flows into the mold.3.2.3PatternsPatterns are used to mold the sand mixture into the shape of the casting. They may be made of wood, plastic, or metal. The selection of a pattern material depends on the size and shape of the casting, the dimensional accuracy, the quantity of castings required, and the molding process.Because patterns are used repeatedly to make molds, the strength and durability of the material selected for patterns must reflect thenumber of castings that the mold will produce.They may be made of a combination of materials to reduce wear in critical regions. Patterns are usually coated with a parting agent to facilitate their removal from the molds.Patterns can be designed with a variety of features to fit application and economic requirements. One-piece patterns, also called loose or solid patterns, are generally used for simpler shapes and low-quantity production. They are generally made of wood and are inexpensive. Split patterns are two-piece patterns made such that each part forms a portion of the cavity for the casting; in this way, castings with complicated shapes can be produced.Match-plate patterns are a popular type of mounted pattern in which two-piece patterns are constructed by securing each half of one or more split patterns to the opposite sides of a single plate (Fig.3-4). In such constructions, the gating system can be mounted on the drag side of the pattern. This type of pattern is used most often in conjunction with molding machines and large production runs to produce smaller castings.Cope sidePlateDrag sideFig. 3-4 A typical metal match-plate pattern used in sand castingAn important recent development is the application of rapid prototyping to moldand pattern making. In sand casting, for example, a pattern can be fabricated in arapid prototyping machine and fastened to a backing plate at a fraction of the timeand cost of machining a pattern. There are several rapid prototyping techniques withwhich these tools can be produced quickly.Pattern design is a crucial aspect of the total casting operation. The design should provide for metal shrinkage, case of removal from the sand mold by means of a taper or draft (Fig.3-5), and proper metal flow in the mold cavity.Pattern Draft angleDamageFlaskSand moldPoor GoodFig. 3-5 Taper on patterns for case of removal from the sand mold3.2.4CoresFor castings with internal cavities or passages, such as those found in an automotive engine block or a valve body, cores are utilized. Cores are placed in themold cavity before casting to form the interior surfaces of the casting and are removed from the finished part during shakeout and further processing. Like molds,cores must possess strength, permeability, ability to withstand heat, and collapsibility; therefore, cores are made of sand aggregates.The core is anchored by core prints. These are recesses that are added to the pattern to support the core and to provide vents for the escape of gases (Fig. 3-6). A common problem with cores is that for some casting requirements, as in the casewhere a recess is required, they may lack sufficient structural support in the cavity.To keep the core from shifting, metal supports (chaplets) may be used to anchor thecore in place (Fig. 3-6).ChapletCore CoreCoreprintsCavity PartinglineMoldCavity CoreprintsFig. 3-6 Examples of sand cores showing core prints and chaplets to support cores8Cores are generally made in a manner similar to that used in making molds; the majority are made with shell, no-bake, or cold-box processes. Cores are formed in core boxes, which are used in much the same way that patterns are used to form sand molds. The sand can be packed into the boxes with sweeps, or blown into the box by compressed air from core blowers. The latter have the advantages of producing uniform cores and operating at very high production rates.3.2.5Sand-Molding MachinesThe oldest known method of molding, which is still used for simple castings, is to compact the sand by hand hammering (tamping) or ramming it around the pattern. For most operations, however, the sand mixture is compacted around the pattern by molding machines (Fig.3-7). These machines eliminate arduous labor, offer high-quality casting by improving the application and distribution of forces, manipulate the mold in a carefully controlled manner, and increase production rate.Squeeze head(a)(c) Equalizing pistons Pressurized air(b)(d)DiaphragmHydraulic cylinderFig. 3-7 Various designs of squeeze heads for mold making(a)conventional flat head (b) profile head (c) equalizing squeeze pistons (d) flexible diaphragmMechanization of the molding process can be further assisted by jolting the assembly. The flask, molding sand, and pattern are first placed on a pattern plate mounted on an anvil, and then jolted upward by air pressure at rapid intervals. The inertial forces compact the sand around the pattern. Jolting produces the highest compaction at the horizontal parting line, whereas in squeezing, compaction is highest at the squeezing head (Fig. 3-7). Thus, more uniform com- paction can be obtained by combining squeezing and jolting.In vertical flaskless molding, the halves of the pattern form a vertical chamber wall against which sand is blown and compacted (Fig. 3-8). Then, the mold haves are packed horizontally, with the parting line oriented vertically and moved along a pouring conveyor. This operation is simple and eliminates the need to handle flasks, allowing for very high production rates, particularly when other aspects of the operation (such as coring and pouring) are automated.Ram forceBoxSandPatternMetal poured here(a)(b)Fig. 3-8 Vertical flaskless molding(a)sand is squeezed between two halves of the pattern(b)assembled molds pass along an assembly line for pouringSandslingers fill the flask uniformly with sand under high-pressure stream. They are used to fill large flasks and are typically operated by machine. An impeller in the machine throws sand from its blades or cups at such high speeds that the machine not only places the sand but also rams it appropriately.In impact molding, the sand is compacted by controlled explosion or instantaneous release of compressed gases. This method produces molds withuniform strength and good permeability.In vacuum molding, also known as the “V” process, the pattern is covered tightly by a thin sheet of plastic. A flask is placed over the coated pattern and is filled with dry binderless sand. A second sheet of plastic is then placed on top of the sand, and a vacuum action hardens the sand so that the pattern can be withdrawn. Both halves of the mold are made this way and assembled.During pouring, the mold remains under a vacuum but the casting cavity does not. When the metal has solidified, the vacuum is turned off and the sand falls away, releasing the casting. Vacuum molding produces castings with high-quality detail and dimensional accuracy. It is especially well suited for large, relatively flat castings.113.2.6The Sand Casting OperationAfter the mold has been shaped and the cores have been placed in position, the two halves (cope and drag) are closed, clamped, and weighted down. They are weighted to prevent the separation of the mold sections under the pressure exerted when the molten metal is poured into the mold cavity.The design of the gating system is important for proper delivery of the molten metal into the mold cavity. As described, turbulence must be minimized, air and gases must be allowed to escape by such means as vents, and proper temperature gradients must be established and maintained to minimize shrinkage and porosity. The design of risers is also important in order to supply the necessary molten metal during solidification of the casting. The pouring basin may also serve as a riser. A complete sequence of operations in sand casting is shown in Fig. 3-9. In Fig. 3-9(a), a mechanical drawing of the part is used to generate a design for the pattern. Considerations such as part shrinkage and draft must be built into the drawing. In (b)~(c), patterns have been mounted on plates equipped with pins for alignment. Note the presence of core prints designed to hold the core in place. In (d)~(e), core boxes produce core halves, which are pasted together. The cores will be used to produce the hollow area of the part shown in (a). In (f), the cope half of the mold is assembled by securing the cope pattern plate to the flask with aligning pins, and attaching inserts to form the sprue and risers. In (g), the flask is rammed with sand and the plate and inserts are removed. In (h), the drag half is produced in a similar manner, with the pattern inserted. A bottom board is placed below the drag and aligned with pins. In (i), the pattern, flask, and bottom board are inverted, and the pattern is withdrawn, leaving the appropriate imprint. In (j), the core is set in place within the drag cavity. In (k), the mold is closed by placing the cope on top of the drag and securing the assembly with pins. The flasks are then subjected to pressure to counteract buoyant forces in the liquid, which might lift the cope. In (l), after the metal solidifies, the casting is removed from the mold. In (m), the sprue and risers are cut off and recycled, and the casting is cleaned, inspected, and heat treated (when necessary).After solidification, the casting is shaken out of its mold, and the sand and oxide layers adhering to the casting are removed by vibration (using a shaker) or by sand blasting. Ferrous castings are also cleaned by blasting with steel shot (shot blasting) or grit. The risers and gates are cut off by oxyfuel-gas cutting, sawing, shearing, andabrasive wheels, or they are trimmed in dies. Gates and risers on steel castings are also removed with air carbon-arc or powder-injection torches. Castings may be cleaned by electrochemical means or by pickling with chemicals to remove surface oxides.(a) (b) (c) Core printsMechanical drawing of part (d) (e)Core boxesCore printsCope pattern plateCore halvespasted together(f)FlaskGateDrag pattern plateRisers SprueCope ready for sand(g) (h) (i)Cope after ramming withsand and removing pattern, sprue, and risers Drag ready for sandDrag afterremoving pattern(j)CopeDrag (k)(l)(m)Drag with core set in place ClosingpinsCope and dragassembled readyfor pouringCasting asremoved frommold; heat treatedCasting readyfor shipmentFig. 3-9 Schematic illustration of the sequence of operations for sand castingAlmost all commercially-used metals can be sand cast. The surface finish obtained is largely a function of the materials used in making the mold. Dimensional accuracy is not as good as that of other casting processes. However, intricate shapes can be cast by this process, such as cast-iron engine blocks and very large propellers for ocean liners. Sand casting can be economical for relatively small production runs, and equipment costs are generally low.The surface of castings is important in subsequent machining operations, because machi- nability can be adversely affected if the castings are not cleaned properly and sand particles remain on the surface. If regions of the casting have not formed properly or have formedincompletely, the defects may be repaired by filling them with weld metal. Sand-mold castings generally have rough, grainy surfaces, depending on the quality of the mold and the materials used.The casting may subsequently be heat-treated to improve certain properties needed for its intended service use; these processes are particularly important for steel castings. Finishing operations may involve machining straightening, or forging with dies to obtain final dimensions.Minor surface imperfections may also be filled with a metal-filled epoxy, especially for cast-iron castings because they are difficult to weld. Inspection is an important final step and is carried out to ensure that the casting meets all design and quality control requirements.第三章铸造模具3.1 铸造第一批铸件是在公元前4000年至公元前3000年制造的。

注塑模具中英文对照外文翻译文献

注塑模具中英文对照外文翻译文献

中英文对照资料外文翻译Integrated simulation of the injection molding process withstereolithography moldsAbstract Functional parts are needed for design verification testing, field trials, customer evaluation, and production planning. By eliminating multiple steps, the creation of the injection mold directly by a rapid prototyping (RP) process holds the best promise of reducing the time and cost needed to mold low-volume quantities of parts. The potential of this integration of injection molding with RP has been demonstrated many times. What is missing is the fundamental understanding of how the modifications to the mold material and RP manufacturing process impact both the mold design and the injection molding process. In addition, numerical simulation techniques have now become helpful tools of mold designers and process engineers for traditional injection molding. But all current simulation packages for conventional injection molding are no longer applicable to this new type of injection molds, mainly because the property of the mold material changes greatly. In this paper, an integrated approach to accomplish a numerical simulation of injection molding into rapid-prototyped molds is established and a corresponding simulation system is developed. Comparisons with experimental results are employed for verification, which show that the present scheme is well suited to handle RP fabricated stereolithography (SL) molds.Keywords Injection molding Numerical simulation Rapid prototyping1 IntroductionIn injection molding, the polymer melt at high temperature is injected into the mold under high pressure [1]. Thus, the mold material needs to have thermal and mechanical properties capable of withstanding the temperatures and pressures of the molding cycle. The focus of many studies has been to create theinjection mold directly by a rapid prototyping (RP) process. By eliminating multiple steps, this method of tooling holds the best promise of reducing the time and cost needed to createlow-volume quantities of parts in a production material. The potential of integrating injection molding with RP technologies has been demonstrated many times. The properties of RP molds are very different from those of traditional metal molds. The key differences are the properties of thermal conductivity and elastic modulus (rigidity). For example, the polymers used in RP-fabricated stereolithography (SL) molds have a thermal conductivity that is less than one thousandth that of an aluminum tool. In using RP technologies to create molds, the entire mold design and injection-molding process parameters need to be modified and optimized from traditional methodologies due to the completely different tool material. However, there is still not a fundamental understanding of how the modifications to the mold tooling method and material impact both the mold design and the injection molding process parameters. One cannot obtain reasonable results by simply changing a few material properties in current models. Also, using traditional approaches when making actual parts may be generating sub-optimal results. So there is a dire need to study the interaction between the rapid tooling (RT) process and material and injection molding, so as to establish the mold design criteria and techniques for an RT-oriented injection molding process.In addition, computer simulation is an effective approach for predicting the quality of molded parts. Commercially available simulation packages of the traditional injection molding process have now become routine tools of the mold designer and process engineer [2]. Unfortunately, current simulation programs for conventional injection molding are no longer applicable to RP molds, because of the dramatically dissimilar tool material. For instance, in using the existing simulation software with aluminum and SL molds and comparing with experimental results, though the simulation values of part distortion are reasonable for the aluminum mold, results are unacceptable, with the error exceeding 50%. The distortion during injection molding is due to shrinkage and warpage of the plastic part, as well as the mold. For ordinarily molds, the main factor is the shrinkage and warpage of the plastic part, which is modeled accurately in current simulations. But for RP molds, the distortion of the mold has potentially more influence, which have been neglected in current models. For instance, [3] used a simple three-step simulation process to consider the mold distortion, which had too much deviation.In this paper, based on the above analysis, a new simulation system for RP molds is developed. The proposed system focuses on predicting part distortion, which is dominating defect in RP-molded parts. The developed simulation can be applied as an evaluation tool for RP mold design and process opti mization. Our simulation system is verified by an experimental example.Although many materials are available for use in RP technologies, we concentrate on usingstereolithography (SL), the original RP technology, to create polymer molds. The SL process uses photopolymer and laser energy to build a part layer by layer. Using SL takes advantage of both the commercial dominance of SL in the RP industry and the subsequent expertise base that has been developed for creating accurate, high-quality parts. Until recently, SL was primarily used to create physical models for visual inspection and form-fit studies with very limited func-tional applications. However, the newer generation stereolithographic photopolymers have improved dimensional, mechanical and thermal properties making it possible to use them for actual functional molds.2 Integrated simulation of the molding process2.1 MethodologyIn order to simulate the use of an SL mold in the injection molding process, an iterative method is proposed. Different software modules have been developed and used to accomplish this task. The main assumption is that temperature and load boundary conditions cause significant distortions in the SL mold. The simulation steps are as follows:1The part geo metry is modeled as a solid model, which is translated to a file readable by the flow analysis package.2Simulate the mold-filling process of the melt into a pho topolymer mold, which will output the resulting temperature and pressure profiles.3Structural analysis is then performed on the photopolymer mold model using the thermal and load boundary conditions obtained from the previous step, which calculates the distortion that the mold undergo during the injection process.4If the distortion of the mold converges, move to the next step. Otherwise, the distorted mold cavity is then modeled (changes in the dimensions of the cavity after distortion), and returns to the second step to simulate the melt injection into the distorted mold.5The shrinkage and warpage simulation of the injection molded part is then applied, which calculates the final distor tions of the molded part.In above simulation flow, there are three basic simulation mod ules.2. 2 Filling simulation of the melt2.2.1 Mathematical modelingIn order to simulate the use of an SL mold in the injection molding process, an iterativemethod is proposed. Different software modules have been developed and used to accomplish this task. The main assumption is that temperature and load boundary conditions cause significant distortions in the SL mold. The simulation steps are as follows:1. The part geometry is modeled as a solid model, which is translated to a file readable by the flow analysis package.2. Simulate the mold-filling process of the melt into a photopolymer mold, which will output the resulting temperature and pressure profiles.3. Structural analysis is then performed on the photopolymer mold model using the thermal and load boundary conditions obtained from the previous step, which calculates the distortion that the mold undergo during the injection process.4. If the distortion of the mold converges, move to the next step. Otherwise, the distorted mold cavity is then modeled (changes in the dimensions of the cavity after distortion), and returns to the second step to simulate the melt injection into the distorted mold.5. The shrinkage and warpage simulation of the injection molded part is then applied, which calculates the final distortions of the molded part.In above simulation flow, there are three basic simulation modules.2.2 Filling simulation of the melt2.2.1 Mathematical modelingComputer simulation techniques have had success in predicting filling behavior in extremely complicated geometries. However, most of the current numerical implementation is based on a hybrid finite-element/finite-difference solution with the middleplane model. The application process of simulation packages based on this model is illustrated in Fig. 2-1. However, unlike the surface/solid model in mold-design CAD systems, the so-called middle-plane (as shown in Fig. 2-1b) is an imaginary arbitrary planar geometry at the middle of the cavity in the gap-wise direction, which should bring about great inconvenience in applications. For example, surface models are commonly used in current RP systems (generally STL file format), so secondary modeling is unavoidable when using simulation packages because the models in the RP and simulation systems are different. Considering these defects, the surface model of the cavity is introduced as datum planes in the simulation, instead of the middle-plane.According to the previous investigations [4–6], fillinggoverning equations for the flow and temperature field can be written as:where x, y are the planar coordinates in the middle-plane, and z is the gap-wise coordinate; u, v,w are the velocity components in the x, y, z directions; u, v are the average whole-gap thicknesses; and η, ρ,CP (T), K(T) represent viscosity, density, specific heat and thermal conductivity of polymer melt, respectively.Fig.2-1 a–d. Schematic procedure of the simulation with middle-plane model. a The 3-D surface model b The middle-plane model c The meshed middle-plane model d The display of the simulation result In addition, boundary conditions in the gap-wise direction can be defined as:where TW is the constant wall temperature (shown in Fig. 2a).Combining Eqs. 1–4 with Eqs. 5–6, it follows that the distributions of the u, v, T, P at z coordinates should be symmetrical, with the mirror axis being z = 0, and consequently the u, v averaged in half-gap thickness is equal to that averaged in wholegap thickness. Based on this characteristic, we can divide the whole cavity into two equal parts in the gap-wise direction, as described by Part I and Part II in Fig. 2b. At the same time, triangular finite elements are generated in the surface(s) of the cavity (at z = 0 in Fig. 2b), instead of the middle-plane (at z = 0 in Fig. 2a). Accordingly, finite-difference increments in the gapwise direction are employed only in the inside of the surface(s) (wall to middle/center-line), which, in Fig. 2b, means from z = 0 to z = b. This is single-sided instead of two-sided with respect to the middle-plane (i.e. from the middle-line to two walls). In addition, the coordinate system is changed from Fig. 2a to Fig. 2b to alter the finite-element/finite-difference scheme, as shown in Fig. 2b. With the above adjustment, governing equations are still Eqs. 1–4. However, the original boundary conditions inthe gapwise direction are rewritten as:Meanwhile, additional boundary conditions must be employed at z = b in order to keep the flows at the juncture of the two parts at the same section coordinate [7]:where subscripts I, II represent the parameters of Part I and Part II, respectively, and Cm-I and Cm-II indicate the moving free melt-fronts of the surfaces of the divided two parts in the filling stage.It should be noted that, unlike conditions Eqs. 7 and 8, ensuring conditions Eqs. 9 and 10 are upheld in numerical implementations becomes more difficult due to the following reasons:1. The surfaces at the same section have been meshed respectively, which leads to a distinctive pattern of finite elements at the same section. Thus, an interpolation operation should be employed for u, v, T, P during the comparison between the two parts at the juncture.2. Because the two parts have respective flow fields with respect to the nodes at point A and point C (as shown in Fig. 2b) at the same section, it is possible to have either both filled or one filled (and one empty). These two cases should be handled separately, averaging the operation for the former, whereas assigning operation for the latter.3. It follows that a small difference between the melt-fronts is permissible. That allowance can be implemented by time allowance control or preferable location allowance control of the melt-front nodes.4. The boundaries of the flow field expand by each melt-front advancement, so it is necessary to check the condition Eq. 10 after each change in the melt-front.5. In view of above-mentioned analysis, the physical parameters at the nodes of the same section should be compared and adjusted, so the information describing finite elements of the same section should be prepared before simulation, that is, the matching operation among the elements should be preformed.Fig. 2a,b. Illustrative of boundary conditions in the gap-wise direction a of the middle-plane model b of thesurface model2.2.2 Numerical implementationPressure field. In modeling viscosity η, which is a function of shear rate, temperature and pressure of melt, the shear-thinning behavior can be well represented by a cross-type model such as:where n corresponds to the power-law index, and τ∗ characterizes the shear stress level of the transition region between the Newtonian and power-law asymptotic limits. In terms of an Arrhenius-type temperature sensitivity and exponential pressure dependence, η0(T, P) can be represented with reasonable accuracy as follows:Equations 11 and 12 constitute a five-constant (n, τ∗, B, Tb, β) representation for viscosity. The shear rate for viscosity calculation is obtained by:Based on the above, we can infer the following filling pressure equation from the governing Eqs. 1–4:where S is calculated by S = b0/(b−z)2η d z. Applying the Galerkin method, the pressure finite-element equation is deduced as:where l_ traverses all elements, including node N, and where I and j represent the local node number in element l_ corresponding to the node number N and N_ in the whole, respectively. The D(l_) ij is calculated as follows:where A(l_) represents triangular finite elements, and L(l_) i is the pressure trial function in finite elements.Temperature field. To determine the temperature profile across the gap, each triangular finite element at the surface is further divided into NZ layers for the finite-difference grid.The left item of the energy equation (Eq. 4) can be expressed as:where TN, j,t represents the temperature of the j layer of node N at time t.The heat conduction item is calculated by:where l traverses all elements, including node N, and i and j represent the local node number in element l corresponding to the node number N and N_ in the whole, respectively.The heat convection item is calculated by:For viscous heat, it follows that:Substituting Eqs. 17–20 into the energy equation (Eq. 4), the temperature equation becomes:2.3 Structural analysis of the moldThe purpose of structural analysis is to predict the deformation occurring in the photopolymer mold due to the thermal and mechanical loads of the filling process. This model is based on a three-dimensional thermoelastic boundary element method (BEM). The BEM is ideally suited for this application because only the deformation of the mold surfaces is of interest. Moreover, the BEM has an advantage over other techniques in that computing effort is not wasted on calculating deformation within the mold.The stresses resulting from the process loads are well within the elastic range of the mold material. Therefore, the mold deformation model is based on a thermoelastic formulation. The thermal and mechanical properties of the mold are assumed to be isotropic and temperature independent.Although the process is cyclic, time-averaged values of temperature and heat flux are used for calculating the mold deformation. Typically, transient temperature variations within a mold have been restricted to regions local to the cavity surface and the nozzle tip [8]. The transients decay sharply with distance from the cavity surface and generally little variation is observed beyond distances as small as 2.5 mm. This suggests that the contribution from the transients to the deformation at the mold block interface is small, and therefore it is reasonable to neglect the transient effects. The steady state temperature field satisfies Laplace’s equation 2T = 0 and the time-averaged boundary conditions. The boundary conditions on the mold surfaces are described in detail by Tang et al. [9]. As for the mechanical boundary conditions, the cavity surface is subjected to the melt pressure, the surfaces of the mold connected to the worktable are fixed in space, and other external surfaces are assumed to be stress free.The derivation of the thermoelastic boundary integral formulation is well known [10]. It is given by:where uk, pk and T are the displacement, traction and temperature,α, ν represent the thermal expansion coefficient and Poisson’s ratio of the material, and r = |y−x|. clk(x) is the surfacecoefficient which depends on the local geometry at x, the orientation of the coordinate frame and Poisson’s ratio for the domain [11]. The fundamental displacement ˜ulk at a point y in the xk direction, in a three-dimensional infinite isotropic elastic domain, results from a unit load concentrated at a point x acting in the xl direction and is of the form:where δlk is the Kronecker delta function and μ is the shear modulus of the mold material.The fundamental traction ˜plk , measured at the point y on a surface with unit normal n, is:Discretizing the surface of the mold into a total of N elements transforms Eq. 22 to:where Γn refers to the n th surface element on the domain.Substituting the appropriate linear shape functions into Eq. 25, the linear boundary element formulation for the mold deformation model is obtained. The equation is applied at each node on the discretized mold surface, thus giving a system of 3N linear equations, where N is the total number of nodes. Each node has eight associated quantities: three components of displacement, three components of traction, a temperature and a heat flux. The steady state thermal model supplies temperature and flux values as known quantities for each node, and of the remaining six quantities, three must be specified. Moreover, the displacement values specified at a certain number of nodes must eliminate the possibility of a rigid-body motion or rigid-body rotation to ensure a non-singular system of equations. The resulting system of equations is assembled into a integrated matrix, which is solved with an iterative solver.2.4 Shrinkage and warpage simulation of the molded partInternal stresses in injection-molded components are the principal cause of shrinkage and warpage. These residual stresses are mainly frozen-in thermal stresses due to inhomogeneous cooling, when surface layers stiffen sooner than the core region, as in free quenching. Based onthe assumption of the linear thermo-elastic and linear thermo-viscoelastic compressible behavior of the polymeric materials, shrinkage and warpage are obtained implicitly using displacement formulations, and the governing equations can be solved numerically using a finite element method.With the basic assumptions of injection molding [12], the components of stress and strain are given by:The deviatoric components of stress and strain, respectively, are given byUsing a similar approach developed by Lee and Rogers [13] for predicting the residual stresses in the tempering of glass, an integral form of the viscoelastic constitutive relationships is used, and the in-plane stresses can be related to the strains by the following equation:Where G1 is the relaxation shear modulus of the material. The dilatational stresses can be related to the strain as follows:Where K is the relaxation bulk modulus of the material, and the definition of α and Θ is:If α(t) = α0, applying Eq. 27 to Eq. 29 results in:Similarly, applying Eq. 31 to Eq. 28 and eliminating strain εxx(z, t) results in:Employing a Laplace transform to Eq. 32, the auxiliary modulus R(ξ) is given by:Using the above constitutive equation (Eq. 33) and simplified forms of the stresses and strains in the mold, the formulation of the residual stress of the injection molded part during the cooling stage is obtain by:Equation 34 can be solved through the application of trapezoidal quadrature. Due to the rapid initial change in the material time, a quasi-numerical procedure is employed for evaluating the integral item. The auxiliary modulus is evaluated numerically by the trapezoidal rule.For warpage analysis, nodal displacements and curvatures for shell elements are expressed as:where [k] is the element stiffness matrix, [Be] is the derivative operator matrix, {d} is the displacements, and {re} is the element load vector which can be evaluated by:The use of a full three-dimensional FEM analysis can achieve accurate warpage results, however, it is cumbersome when the shape of the part is very complicated. In this paper, a twodimensional FEM method, based on shell theory, was used because most injection-molded parts have a sheet-like geometry in which the thickness is much smaller than the other dimensions of the part. Therefore, the part can be regarded as an assembly of flat elements to predict warpage. Each three-node shell element is a combination of a constant strain triangular element (CST) and a discrete Kirchhoff triangular element (DKT), as shown in Fig. 3. Thus, the warpage can be separated into plane-stretching deformation of the CST and plate-bending deformation of the DKT, and correspondingly, the element stiffness matrix to describe warpage can also be divided into the stretching-stiffness matrix and bending-stiffness matrix.Fig. 3a–c. Deformation decomposition of shell element in the local coordinate system. a In-plane stretchingelement b Plate-bending element c Shell element3 Experimental validationTo assess the usefulness of the proposed model and developed program, verification is important. The distortions obtained from the simulation model are compared to the ones from SL injection molding experiments whose data is presented in the literature [8]. A common injection molded part with the dimensions of 36×36×6 mm is considered in the experiment, as shown in Fig. 4. The thickness dimensions of the thin walls and rib are both 1.5 mm; and polypropylene was used as the injection material. The injection machine was a production level ARGURY Hydronica 320-210-750 with the following process parameters: a melt temperature of 250 ◦C; an ambient temperature of 30 ◦C; an injection pressure of 13.79 MPa; an injection time of 3 s; and a cooling time of 48 s. The SL material used, Dupont SOMOSTM 6110 resin, has the ability to resist temperatures of up to 300 ◦C temperatures. As mentioned above, thermal conductivity of the mold is a major factor that differentiates between an SL and a traditional mold. Poor heat transfer in the mold would produce a non-uniform temperature distribution, thus causing warpage that distorts the completed parts. For an SL mold, a longer cycle time would be expected. The method of using a thin shell SL mold backed with a higher thermal conductivity metal (aluminum) was selected to increase thermal conductivity of the SL mold.Fig. 4. Experimental cavity modelFig. 5. A comparison of the distortion variation in the X direction for different thermal conductivity; where “Experimental”, “present”, “three-step”, and “conventional” mean the results of the experimental, the presented simulation, the three-step simulation process and the conventional injection molding simulation, respectively.Fig. 6. Comparison of the distortion variation in the Y direction for different thermal conductivitiesFig. 7. Comparison of the distortion variation in the Z direction for different thermal conductivitiesFig. 8. Comparison of the twist variation for different thermal conductivities For this part, distortion includes the displacements in three directions and the twist (the difference in angle between two initially parallel edges). The validation results are shown in Fig.5 to Fig. 8. These figures also include the distortion values predicted by conventional injection molding simulation and the three-step model reported in [3].4 ConclusionsIn this paper, an integrated model to accomplish the numerical simulation of injection molding into rapid-prototyped molds is established and a corresponding simulation system is developed. For verification, an experiment is also carried out with an RPfabricated SL mold.It is seen that a conventional simulation using current injection molding software breaks down for a photopolymer mold. It is assumed that this is due to the distortion in the mold caused by the temperature and load conditions of injection. The three-step approach also has much deviation. The developed model gives results closer to experimental.Improvement in thermal conductivity of the photopolymer significantly increases part quality. Since the effect of temperature seems to be more dominant than that of pressure (load), an improvement in the thermal conductivity of the photopolymer can improve the part quality significantly.Rapid Prototyping (RP) is a technology makes it possible to manufacture prototypes quickly and inexpensively, regardless of their complexity. Rap id Tooling (RT) is the next step in RP’s steady progress and much work is being done to obtain more accurate tools to define the parameters of the process. Existing simulation tools can not provide the researcher with a useful means of studying relative changes. An integrated model, such as the one presented in this paper, is necessary to obtain accurate predictions of the actual quality of final parts. In the future, we expect to see this work expanded to develop simulations program for injection into RP molds manufactured by other RT processes.References1. Wang KK (1980) System approach to injection molding process. Polym-Plast Technol Eng 14(1):75–93.2. Shelesh-Nezhad K, Siores E (1997) Intelligent system for plastic injection molding process design. J Mater Process Technol 63(1–3):458–462.3. Aluru R, Keefe M, Advani S (2001) Simulation of injection molding into rapid-prototyped molds. Rapid Prototyping J 7(1):42–51.4. Shen SF (1984) Simulation of polymeric flows in the injection molding process. Int J Numer Methods Fluids 4(2):171–184.5. Agassant JF, Alles H, Philipon S, Vincent M (1988) Experimental and theoretical study of the injection molding of thermoplastic materials. Polym Eng Sci 28(7):460–468.6. Chiang HH, Hieber CA, Wang KK (1991) A unified simulation of the filling and post-filling stages in injection molding. Part I: formulation. Polym Eng Sci 31(2):116–124.7. Zhou H, Li D (2001) A numerical simulation of the filling stage in injection molding based on a surface model. Adv Polym Technol 20(2):125–131.8. Himasekhar K, Lottey J, Wang KK (1992) CAE of mold cooling in injection molding using a three-dimensional numerical simulation. J EngInd Trans ASME 114(2):213–221.9. Tang LQ, Pochiraju K, Chassapis C, Manoochehri S (1998) Computeraided optimization approach for the design of injection mold cooling systems. J Mech Des, Trans ASME 120(2):165–174.10. Rizzo FJ, Shippy DJ (1977) An advanced boundary integral equation method for three-dimensional thermoelasticity. Int J Numer Methods Eng 11:1753–1768.11. Hartmann F (1980) Computing the C-matrix in non-smooth boundary points. In: New developments in boundary element methods, CML Publications, Southampton, pp 367–379.12. Chen X, Lama YC, Li DQ (2000) Analysis of thermal residual stress in plastic injection molding. J Mater Process Technol 101(1):275–280.13. Lee EH, Rogers TG (1960) Solution of viscoelastic stress analysis problems using measured creep or relaxation function. J Appl Mech 30(1):127–134.14. Li Y (1997) Studies in direct tooling using stereolithography. Dissertation, University of Delaware, Newark, DE..。

模具外文资料翻译

模具外文资料翻译

附件1:外文资料翻译译文注塑模具设计系统中侧向分型特征的识别摘要在塑料模具的设计中,破坏特征的存在将会影响到模具的成本和结构。

简要说明侧向分型的定义、分类的特点及相关概念,以以比较容易识别的使用方法。

通过该侧向分型特征定义、分类侧向分型之间的关系,特点及其作用的简要论述,明确了侧向分型的定义特征参数及计算方法。

V-maps介绍了侧向分型的特点,范围,方向和侧向分型的特征。

由于侧向分型的特点可以部分的确认其识别方法。

考虑到混合表面,由于实际结构和虚拟结构有第一相邻表面,所以对实际和虚拟的边缘也提出了建议。

,对于破坏特征识别准则进行讨论后,破坏特征,可被持续不断地认识。

工业案例研究表明,在复杂的注射模部分,该方法的发展能有效的识别和提取侧向分型特征。

关键词:侧向分型;特征识别计算机辅助设计;注射模具的设计1 介绍模具制造是一个重要的支柱产业,因为他们在消费产品种超过70%的非标准部件的消费产品。

在模具的生产运行过程中,通常会有极小的尺寸和极大的品种。

保证较短的订货时间的需求,较高的设计和制造和综合素质以及可以快速改变设计上的瓶颈,已成为模具行业对模具公司保持竞争力的优势。

偶有迫切需要缩短交货的时间的设计,就需要生产设计过程中使用先进的自动化生产设备,先进的加工工艺,并且提高员工的技术水平。

目前,一些模具公司使用三维商业CAD软件工具设计模具,然而,许多公司仍然在设计当中,模具手动操作时,容易出错。

开发的一种计算机辅助注射模设计系统(CAIMDS)就成为了工业产业、学术界研究的焦点。

2. 侧向分型的定义与分类特征在模具的凹模,例如当凹穴、槽孔的口袋和漏洞是潜在的特征;而凸模,例如缸、锥和球体同样可以是侧向分型的特点。

如果腔和他们的插入不能塑造侧向分型特征,侧向凸板或侧向凹板或其他的工具必须与模具结构相适应。

在图1,有三种侧向分型,特点是乙、丙在塑造的部分。

如果那离别的方向图中选择,那么侧向分型可以被塑造特色的核心内容,但侧向分型特点B和C不能被塑造并且插入,前提为凸板和凹板均已成型。

模具设计与制造外文翻译参考文献

模具设计与制造外文翻译参考文献

模具设计与制造外文翻译参考文献(文档含中英文对照即英文原文和中文翻译)译文:模具设计与制造模具是制造业的重要工艺基础,在我国模具制造属于专用设备制造业。

中国虽然很早就开始制造模具和使用模具,但长期未形成产业。

直到20世纪80年代后期,中国模具工业才驶入发展的快车道。

近年,不仅国有模具企业有了很大发展,三资企业、乡镇(个体)模具企业的发展也相当迅速。

虽然中国模具工业发展迅速,但与需求相比,显然供不应求,其主要缺口集中于精密、大型、复杂、长寿命模具领域。

由于在模具精度、寿命、制造周期及生产能力等方面,中国与国际平均水平和发达国家仍有较大差距,因此,每年需要大量进口模具。

中国模具产业除了要继续提高生产能力,今后更要着重于行业内部结构的调整和技术发展水平的提高。

结构调整方面,主要是企业结构向专业化调整,产品结构向着中高档模具发展,向进出口结构的改进,中高档汽车覆盖件模具成形分析及结构改进、多功能复合模具和复合加工及激光技术在模具设计制造上的应用、高速切削、超精加工及抛光技术、信息化方向发展。

近年,模具行业结构调整和体制改革步伐加大,主要表现在,大型、精密、复杂、长寿命、中高档模具及模具标准件发展速度高于一般模具产品;塑料模和压铸模比例增大;专业模具厂数量及其生产能力增加;“三资”及私营企业发展迅速;股份制改造步伐加快等。

从地区分布来看,以珠江三角洲和长江三角洲为中心的东南沿海地区发展快于中西部地区,南方的发展快于北方。

目前发展最快、模具生产最为集中的省份是广东和浙江,江苏、上海、安徽和山东等地近几年也有较大发展。

虽然我国模具总量目前已达到相当规模,模具水平也有很大提高,但设计制造水平总体上落后于德、美、日、法、意等工业发达国家许多。

当前存在的问题和差距主要表现在以下几方面:(1)总量供不应求,国内模具自配率只有70%左右。

其中低档模具供过于求,中高档模具自配率只有50%左右。

(2)企业组织结构、产品结构、技术结构和进出口结构均不合理。

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。

冲压模具技术外文文献翻译中英文

冲压模具技术外文文献翻译中英文

外文文献翻译(含:英文原文及中文译文)英文原文Stamping technologyIntroductionIn the current fierce market competition, the product to market sooner or later is often the key to the success or failure. Mould is a product of high quality, high efficiency production tool, mold development cycle of the main part of the product development cycle. So the customer requirements for mold development cycle shorter, many customers put the mould delivery date in the first place, and then the quality and price. Therefore, how to ensure the quality, control the cost under the premise of processing mould is a problem worthy of serious consideration. Mold processing technology is an advanced manufacturing technology, has become an important development direction, in the aerospace, automotive, machinery and other industries widely used. Mold processing technology, can improve the comprehensive benefit and competitiveness of manufacturing industry. Research and establish mold process database, provide production enterprises urgently need to high speed cutting processing data, to the promotion of high-speed machining technology has very important significance. This article's main goal is to build a stamping die processing, mold manufacturing enterprises in theactual production combined cutting tool, workpiece and machine tool with the actual situation of enterprise itself accumulate to high speed cutting processing instance, process parameters and experience of high speed cutting database selectively to store data, not only can save a lot of manpower and material resources, financial resources, but also can guide the high speed machining production practice, to improve processing efficiency, reduce the tooling cost and obtain higher economic benefits.1. The concept, characteristics and application of stampingStamping is a pressure processing method that uses a mold installed on a press machine (mainly a press) to apply pressure to a material to cause it to separate or plastically deform, thereby obtaining a desired part (commonly referred to as a stamped or stamped part). Stamping is usually cold deformation processing of the material at room temperature, and the main use of sheet metal to form the required parts, it is also called cold stamping or sheet metal stamping. Stamping is one of the main methods of material pressure processing or plastic processing, and is affiliated with material forming engineering.The stamping die is called stamping die, or die. Dies are special tools for the batch processing of materials (metal or non-metallic) into the required stampings. Stamping is critical in stamping. There is no die that meets the requirements. Batch stamping production is difficult. Without advanced stamping, advanced stamping processes cannot be achieved.Stamping processes and dies, stamping equipment, and stamping materials constitute the three elements of stamping. Only when they are combined can stampings be obtained.Compared with other methods of mechanical processing and plastic processing, stamping processing has many unique advantages in both technical and economic aspects, and its main performance is as follows;(1) The stamping process has high production efficiency, easy operation, and easy realization of mechanization and automation. This is because stamping is accomplished by means of die and punching equipment. The number of strokes for ordinary presses can reach several tens of times per minute, and the high-speed pressure can reach hundreds or even thousands of times per minute, and each press stroke is Y ou may get a punch.(2) Since the die ensures the dimensional and shape accuracy of the stamping part during stamping, and generally does not destroy the surface quality of the stamping part, the life of the die is generally longer, so the stamping quality is stable, the interc hangeability is good, and it has “the same” Characteristics.(3) Stamping can process parts with a wide range of sizes and shapes, such as stopwatches as small as clocks, as large as automobile longitudinal beams, coverings, etc., plus the cold deformation hardening effect of materials during stamping, the strength of stamping and Thestiffness is high.(4) Stamping generally does not generate scraps, material consumption is less, and no other heating equipment is required. Therefore, it is a material-saving and energy-saving processing method, and the cost of stamping parts is low.However, the molds used for stamping are generally specialized, and sometimes a complex part requires several sets of molds for forming, and the precision of the mold manufacturing is high and the technical requirements are high. It is a technology-intensive product. Therefore, the advantages of stamping can only be fully realized in the case of large production volume of stamping parts, so as to obtain better economic benefits.Stamping is widely used in modern industrial production, especially in mass production. A considerable number of industrial sectors are increasingly using punching to process product components such as automobiles, agricultural machinery, instruments, meters, electronics, aerospace, aerospace, home appliances, and light industry. In these industrial sectors, the proportion of stamped parts is quite large, at least 60% or more, and more than 90%. Many of the parts that were manufactured in the past using forging = casting and cutting processes are now mostly replaced by light-weight, rigid stampings. Therefore, it can be said that if the stamping process cannot be adopted in production, it isdifficult for many industrial departments to increase the production efficiency and product quality, reduce the production cost, and quickly replace the product.2. Basic process and mould for stampingDue to the wide variety of stamped parts and the different shapes, sizes, and precision requirements of various parts, the stamping process used in production is also varied. Summarized, can be divided into two major categories of separation processes and forming processes; Separation process is to make the blank along a certain contour line to obtain a certain shape, size and section quality stamping (commonly referred to as blanking parts) of the process; forming process refers to The process of producing a stamped part of a certain shape and size by plastic deformation of the blank without breaking.The above two types of processes can be divided into four basic processes: blanking, bending, deep drawing and forming according to different basic deformation modes. Each basic process also includes multiple single processes.In actual production, when the production volume of the stamped part is large, the size is small and the tolerance requirement is small, it is not economical or even difficult to achieve the requirement if the stamping is performed in a single process. At this time, a centralized scheme is mostly used in the process, that is, two or more singleprocesses are concentrated in a single mold. Different methods are called combinations, and they can be divided into compound-graded and compound- Progressive three combinations.Composite stamping - A combination of two or more different single steps at the same station on the die in one press stroke.Progressive stamping - a combination of two or more different single steps on a single work station in the same mold at a single working stroke on the press.Composite - Progressive - On a die combination process consisting of composite and progressive two ways.There are many types of die structure. According to the process nature, it can be divided into blanking die, bending die, drawing die and forming die, etc.; the combination of processes can be divided into single-step die, compound die and progressive die. However, regardless of the type of die, it can be regarded as consisting of two parts: the upper die and the lower die. The upper die is fixed on the press table or the backing plate and is a fixed part of the die. During work, the blanks are positioned on the lower die surface by positioning parts, and the press sliders push the upper die downwards. The blanks are separated or plastically deformed under the action of the die working parts (ie, punch and die) to obtain the required Shape and size of punching pieces. When the upper mold is lifted, the unloading and ejecting device of the moldremoves or pushes and ejects the punching or scrap from the male and female molds for the next punching cycle.3. Current status and development direction of stamping technologyWith the continuous advancement of science and technology and the rapid development of industrial production, many new technologies, new processes, new equipment, and new materials continue to emerge, thus contributing to the constant innovation and development of stamping technology. Its main performance and development direction are as follows:(1) The theory of stamping and the stamping process The study of stamping forming theory is the basis for improving stamping technology. At present, the research on the stamping forming theory at home and abroad attaches great importance, and significant progress has been made in the study of material stamping performance, stress and strain analysis in the stamping process, study of the sheet deformation law, and the interaction between the blank and the mold. . In particular, with the rapid development of computer technology and the further improvement of plastic deformation theory, computer simulation techniques for the plastic forming process have been applied at home and abroad in recent years, namely the use of finite element (FEM) and other valuable analytical methods to simulate the plastic forming process of metals. According to the analysis results, the designer can predict the feasibility and possiblequality problems of a certain process scheme. By selecting and modifying the relevant parameters on the computer, the process and mold design can be optimized. This saves the cost of expensive trials and shortens the cycle time.Research and promotion of various pressing technologies that can increase productivity and product quality, reduce costs, and expand the range of application of stamping processes are also one of the development directions of stamping technology. At present, new precision, high-efficiency, and economical stamping processes, such as precision stamping, soft mold forming, high energy high speed forming, and dieless multi-point forming, have emerged at home and abroad. Among them, precision blanking is an effective method for improving the quality of blanking parts. It expands the scope of stamping processing. The thickness of precision blanking parts can reach 25mm at present, and the precision can reach IT16~17; use liquid, rubber, polyurethane, etc. Flexible die or die soft die forming process can process materials that are difficult to process with ordinary processing methods and parts with complex shapes, have obvious economic effects under specific production conditions, and adopt energy-efficient forming methods such as explosion for processing. This kind of sheet metal parts with complex dimensions, complex shapes, small batches, high strength and high precision has important practical significance; Superplastic forming of metal materialscan be used to replace multiple common stampings with one forming. Forming process, which has outstanding advantages for machining complex shapes and large sheet metal parts; moldless multi-point forming process is an advanced technology for forming sheet metal surfaces by replacing the traditional mold with a group of height adjustable punches. Independently designed and manufactured an international leading-edge moldless multi-point forming equipment, which solves the multi-point press forming method and can therefore be Changing the state of stress and deformation path, improving the forming limit of the material, while repeatedly using the forming technology may eliminate the residual stress within the material, the rebound-free molding. The dieless multi-point forming system takes CAD/CAM/CAE technology as the main means to quickly and economically realize the automated forming of three-dimensional surfaces.(2) Dies are the basic conditions for achieving stamping production. In the design and manufacture of stampings, they are currently developing in the following two aspects: On the one hand, in order to meet the needs of high-volume, automatic, precision, safety and other large-volume modern production, stamping is To develop high-efficiency, high-precision, high-life, multi-station, and multi-function, compared with new mold materials and heat treatment technologies, various high-efficiency, precision, CNC automatic mold processing machine toolsand testing equipment and molds CAD/CAM technology is also rapidly developing; On the other hand, in order to meet the needs of product replacement and trial production or small-batch production, zinc-based alloy die, polyurethane rubber die, sheet die, steel die, combination die and other simple die And its manufacturing technology has also been rapidly developed.Precision, high-efficiency multi-station and multi-function progressive die and large-scale complex automotive panel die represent the technical level of modern die. At present, the precision of the progressive die above 50 stations can reach 2 microns. The multifunctional progressive die can not only complete the stamping process, but also complete welding, assembly and other processes. Our country has been able to design and manufacture its own precision up to the international level of 2 to 5 microns, precision 2 to 3 microns into the distance, the total life of 100 million. China's major automotive mold enterprises have been able to produce complete sets of car cover molds, and have basically reached the international level in terms of design and manufacturing methods and means. However, the manufacturing methods and methods have basically reached the international level. The mold structure and function are also close to international Level, but there is still a certain gap compared with foreign countries in terms of manufacturing quality, accuracy, manufacturing cycle and cost.4. Stamping standardization and professional productionThe standardization and professional production of molds has been widely recognized by the mold industry. Because the die is a single-piece, small-volume production, the die parts have both certain complexity and precision, as well as a certain structural typicality. Therefore, only the standardization of the die can be achieved, so that the production of the die and the die parts can be professionalized and commercialized, thereby reducing the cost of the die, improving the quality of the die and shortening the manufacturing cycle. At present, the standard production of molds in foreign advanced industrial countries has reached 70% to 80%. Mould factories only need to design and manufacture working parts, and most of the mold parts are purchased from standard parts factories, which greatly increases productivity. The more irregular the degree of specialization of the mold manufacturing plant, the more and more detailed division of labor, such as the current mold factory, mandrel factory, heat treatment plant, and even some mold factories only specialize in the manufacture of a certain type of product or die The bending die is more conducive to the improvement of the manufacturing level and the shortening of the manufacturing cycle. China's stamp standardization and specialized production have also witnessed considerable development in recent years. In addition to the increase in the number of standard parts specialized manufacturers, the number ofstandard parts has also expanded, and the accuracy has also improved. However, the overall situation can not meet the requirements of the development of the mold industry, mainly reflected in the standardization level is not high (usually below 40%), the standard parts of the species and specifications are less, most standard parts manufacturers did not form a large-scale production, standard parts There are still many problems with quality. In addition, the sales, supply, and service of standard parts production have yet to be further improved.中文译文冲压模具技术前言在目前激烈的市场竞争中, 产品投入市场的迟早往往是成败的关键。

先进铸造技术动态建模过程和模具设计毕业论文中英文资料对照外文翻译文献综述

先进铸造技术动态建模过程和模具设计毕业论文中英文资料对照外文翻译文献综述

原文:《Modelling the dynamics of the tilt-casting process and the effect of the mould design on the casting quality》H. Wang a,G. Djambazov a, K.A. Pericleous a, R.A. Harding b, M. Wickins bCentre for Numerical Modelling and Process Analysis, University of Greenwich, London SE10 9LS, UK b IRC in Materials Processing, University of Birmingham, Birmingham, B15 2TT, UAbstractAll titanium alloys are highly reactive in the molten condition and so are usually melted in a water-cooled copper crucible to avoid contamination using processes such as Induction Skull Melting (ISM). These provide only limited superheat which, coupled with the surface turbulence inherent in most conventional mould filling processes, results in entrainment defects such as bubbles in the castings. To overcome these problems, a novel tilt-casting process has been developed in which the mould is attached directly to the ISM crucible holding the melt and the two are then rotated together to achieve a tranquil transfer of the metal into the mould. From the modelling point of view, this process involves complex three-phase flow, heat transfer and solidification. In this paper, the development of a numerical model of the tilt-casting process is presented featuring several novel algorithm developments introduced into a general CFD package (PHYSICA) to model the complex dynamic interaction of the liquid metal and melting atmosphere. These developments relate to the front tracking and heat transfer representations and to a casting-specific adaptation of the turbulence model to account for an advancing solid front. Calculations have been performed for a 0.4 m long turbine blade cast in a titanium aluminide alloy using different mould designs. It is shown that the feeder/basin configuration has a crucial influence on the casting quality. The computational results are validated against actual castings and are used to support an experimental programme. Although fluid flow and heat transfer are inseparable in a casting, the emphasis in this paper will be on the fluid dynamics of mould filling and its influence on cast quality rather than heat transfer and solidification which has been reported elsewhere.KeywordsTilt-casting; Mould design; 3-D computational model; Casting process;1. IntroductionThe casting process is already many centuries old, yet many researchers are still devoted to its study. Net shape casting is very attractive from the cost point of view compared to alternative component manufacturing methods such as forging or machining. However, reproducible qualityis still an issue; the elimination of defects and control of microstructure drive research. Casting involves first the filling of the mould and subsequently the solidification of the melt. From the numerical modelling point of view, this simple sequence results in a very complex three-phase problem to simulate. A range of interactions of physical phenomena are involved including free surface fluid flow as the mould fills, heterogeneous heat transfer from the metal to the mould, solidification of the molten metal as it cools, and the development of residual stresses and deformation of the solidified component.In industry there are many variants of the casting process such as sand casting, investment casting, gravity, and low and high pressure die casting. In this study, the investment casting process, also called lost-wax casting, has been investigated. One of the advantages of this process is that it is capable of producing (near) net shape parts, which is particularly important for geometrically complex and difficult-to-machine components. This process starts with making a ceramic mould which involves three main steps: injecting wax into a die to make a replica of the component and attaching this to a pouring basin and running system; building a ceramic shell by the application of several layers of a ceramic slurry and ceramic stucco to the wax assembly; de-waxing and mould firing. The pouring of the casting is performed either simply under gravity (no control), or using a rapid centrifugal action [1] (danger of macro-segregation plus highly turbulent filling), or by suction as in counter-gravity casting (e.g. the Hitchiner process[2]), or by tilt-casting. In this study, tilt-casting was chosen in an attempt to achieve tranquil mould filling. Tilt-casting was patented in 1919 by Durville [3] and has been successfully used with sand castings[4] and aluminium die castings[5]. In the IMPRESS project [6], a novel process has been proposed and successfully developed to combine Induction Skull Melting (ISM) of reactive alloys with tilt-casting[7], [8], [9] and [10], with a particular application to the production of turbine blades in titanium aluminidealloys. As shown in Fig. 1, this is carried out inside a vacuum chamber and the mould is pre-heated in situ to avoid misruns (incomplete mould filling due to premature solidification) and mould cracking due to thermal shock.Tilt-casting process: (a) experimental equipment; (b) schematic view of the ISM crucible and mould, showing the domed shape acquired by the molten metal; (c) different stages of mould filling showing the progressive replacement of gas by the metal.The component(s) to be cast are attached to a pouring basin which also doubles as a source of metal to feed the solidification shrinkage. The components are angled on the basin to promote the progressive uni-directional flow of metal into the mould. As the metal enters the mould it displaces the gas and an escape route has to be included in the design so that the two counter-flowing streams are not mixed leading to bubbles trapped in the metal. Vents are also used to enable any trapped gas to escape. The ‘feeder’ used to connect the mould to the crucible is normally in any casting the last portion of metal to solidify, so supplying metal to the mould to counter the effects of solidification shrinkage. In tilt-casting, the feeder is also the conduit for the tranquil flow of metal into the mould and also for the unhindered escape of gas. For this reason, the fluid dynamics of the mould feeder interface merit detailed study.As well as the mould/feeder design, the production of castings involves several other key parameters, such as the metal pouring temperature, initial mould temperature, selective mould insulation and the tilt cycle timing. All these parameters have an influence on the eventual quality of the casting leading to a very large matrix of experiments. Modelling (once validated) is crucial in reducing the amount of physical experiments required. As mentioned above, the mathematical models are complex due to the fact that this is a three-phase problem with two rapidly developing phase fronts (liquid/gas and solid/liquid). In this paper, a 3-D computational model is used to simulate the tilt-casting process and to investigate the effect of the design of the basin/feeder on the flow dynamics during mould filling and eventually on casting quality.2. Experimental descriptionDetails of the experimental setup have been published elsewhere [11], but for completeness a summary description is given here. Fig. 1a shows an overall view of the equipment used to perform the casting. The Induction Skull Melting (ISM) copper crucible is installed inside a vacuum chamber. To enable rotation, it is attached to a co-axial power feed, which also allows cooling water containing ethylene glycol to be supplied to the ISM crucible and the induction coil. The coil supplies a maximum of 8 kA at a frequency of ∼6 kHz. The crucible wall is segmented, so that the induction field penetrates through the slots (by inducing eddy currents into each finger segment) to melt the charge and at the same time repel the liquid metal away from the side wall to minimise the loss of superheat. A billet of TiAl alloy is loaded into the crucible before clamping on the ceramic shell mould. The mould is surrounded by a low thermal mass split-mould heater. After evacuating the vacuum chamber, the mould is heated to the required temperature (1200 °C maximum) and the vessel back-filled with argon to a partial pressure of 20 kPa prior to melting. This pressure significantly reduces the evaporative loss of the volatile aluminium contained in the alloy. The power applied to the induction coil is increased according to a pre-determined power vs. time schedule so that a reproducible final metal temperature is achieved. At the end of melting (7–8 min), the mould heater is opened and moved away. The induction melting power is rampeddown and, simultaneously, the ISM crucible and mould are rotated by 180° using a programmable controller to transfer the metal into the mould. The mould containing the casting is held vertically as the metal solidifies and cools down.3. Mathematical model3.1. Fluid flow equationsThe modelling of the castingprocess has involved a number of complex computational techniques since there are a range of physical interactions to account for: free surface fluid flow, turbulence, heat transfer and solidification, and so on. The fluid flow dynamics of the molten metal and the gas filling the rest of the space are governed by the Navier–Stokes equations, and a 3D model is used to solve the incompressible time-dependent flow:(1)(2)where u is the fluid velocity vector; ρ is the density; μ is the fluid viscosity; Su is a source term which contains body forces (such as gravitational force, a resistive force (Darcy term) [12]) and the influence of boundaries. There is a sharp, rapidly evolving, property interface separating metal and gas regions in these equations as explained below.3.2. Free surface: counter diffusion method (CDM)One of the difficulties of the simulation arises from the fact that two fluid media are present during filling: liquid metal and resident gas and their density ratio is as high as 10,000:1. Not only does the fluid flow problem need to be solved over the domain, but the model also has to track the evolution of the interface of the two media with time. A scalar fluid marker Φ was introduced to represent the metal volume fraction in a control volume and used to track the interface of the two fluids, called the Scalar Equation Algorithm (SEA) by Pericleous et al. [14]. In a gas cell, Φ = 0; in a metal cell, Φ = 1; for a partially filled cell Φ takes on an intermediate value which the interface of the two media crosses through. The dynamics of the interface are governed by the advection equation:(3)The interface then represents a moving property discontinuity in the domain, which has to be handled carefully to avoid numerical smearing. As in [14], an accurate explicit time stepping scheme such as that by Van Leer [15] may be used to prevent smearing. However, the scheme is then limited to extremely small time steps for stability, leading to very lengthy computations. To overcome this problem, a new tracking method, the counter diffusion method (CDM) [11] and [16], was developed as a corrective mechanism to counter this ‘numerical diffusion’. Thisdiscretizes the free surface equation in a stable, fully implicit scheme which makes the computations an order of magnitude faster. The implementation assumes that an interface-normal counter diffusion flux can be defined for each internal face of the computational mesh and applied with opposite signs to elements straddling the interface as source terms for the marker variable. The equation for the flux per unit area F can be written as:(4)where C is a scaling factor, a free parameter in CDM allowing the strength of the counter diffusion action to be adjusted, and n is the unit normal vector to the face in the mesh. Of the two cells either side of the face, the one w ith the lower value of the marker ΦD becomes the donor cell while the ‘richer’ cell ΦA is the acceptor (in order to achieve the counter diffusion action). The proposed formula makes the counter diffusion action self-limiting as it is reduced to zero where the donor approaches zero (gas) and where the acceptor reaches unity (liquid). In this form, the adjustment remains conservative. Quantitative validation of CDM against other VOF type techniques is given in a later section of the paper for accuracy and efficiency.3.3. Heat transfer and solidificationHeat transfer takes place between the metal, mould and gas, and between cold and hot metal regions as the mould filling is carried out. The heat flow is computed by a transient energy conservation equation:(5)where T is the temperature; k is the thermal conductivity; cp is the specific heat (properties can be functions of the local temperature or other variables); ST is the source term which represents viscous dissipation, boundary heat transfer and latent heat contributions when a phase change occurs. For the latter, a new marker variable fL is used to represent the liquid fraction of the metal with (1 − fL) being the volume fraction of solidified metal. V oller et al. [13] used a non-linear temperature function to calculate the liquid fraction. In this study, the liquid fraction is assumed to be a linear function of the metal temperature:(6)TL is the liquidus temperature and TS is the solidus temperature.3.4. LVEL turbulence model (applied to solid moving boundaries)Even at low filling speeds, the Reynolds number is such that the flow is turbulent. The LVEL method of Spalding [17] is chosen to compute the turbulence because of its mixing-length simplicity and robustness. LVEL is an abbreviation of a distance from the nearest wall (L) and the local velocity (VEL). The approximate wall distance is solved by the Eqs. (7) and (8):(7)∇·(∇W)=-1where W is an auxiliary variable in the regions occupied by the moving fluid with boundary conditions W = 0 on all solid walls.(8)This distance and the local velocity are used in the calculation of the local Reynolds number from which the local value of the turbulent viscosity νt is obtained using a universal non-dimensional velocity profile away from the wall. The effective turbulent viscosity is then computed from the following equation:(9)where κ = 0.417 is the von Karman constant, E = 8.6 is the logarithmic law constant [17] and u+ is determined implicitly from the local Reynolds number Reloc = uL/ν with the magnitude of the local velocity u and the laminar kinematic viscosity ν[17]. The LVEL method was extended to moving solid boundaries and in particular to solidifying regions by setting W = 0 in every region that is no longer fluid and then solving Eqs. (7) and (8) at each time step.In simulating the tilt-casting process, the geometry is kept stationary and the gravitational force vector is rotated to numerically model the tilt instead of varying the coordinates of the geometry. The rotating gravitational force vector appears in the source term of Eq. (1) for the tilt-casting process. A mathematical expression relating the tilting speed to the tilting angle θ has been used. Since θ is a function of time, the variable rotation speed is adjustable to achieve tranquil filling. This technique neglects rotational forces within the fluid (centrifugal, Coriolis) since they are negligible at the slow rotation rates encountered in tilt-casting. Finally, the numerical model of the tilt-casting process and the new algorithm developments were implemented in the general CFD package (PHYSICA).4. Description of simulations4.1. Geometry, mould design and computational meshThe casting is a generic 0.4 m-long turbine blade typical of that used in an Industrial Gas Turbine. Fig. 2 shows three mould designs which comprise the blade, a feeder/basin and a cylindrical crucible. Fig. 2a incorporates a separate cube-shaped feeder that partially links the root of the blade and the basin. Fig. 2b is a variant in which the plane of the blade is rotated through 90°. In both cases, the computational mesh contains 31,535 elements and 38,718 points. Six vents are located on the platform and the shroud of the blade, as seen in Fig. 2a and b. Fig. 2c is an optimised design where the feeder and basin are combined to provide a smooth connection between the blade and the crucible. Two vents are located in the last areas to be filled to help entrapped gas to escape from the mould. Mesh of the crucible-mould assembly for the three casesinvestigated.The mesh for the last case contains 30,185 elements and 37,680 vertices. As in all the cases presented, numerical accuracy depends on mesh fineness and also the degree of orthogonality. To ensure a mostly orthogonal mesh the various components of the assembly were created separately using a structured body-fitted mesh generator and then joined using a mixture of hexahedral and tetrahedral cells. The mesh was refined as necessary in thin sections (such as the blade itself or the shroud and base plates), but not necessarily to be fine enough to resolve boundary layer details. For this reason the LVEL turbulence model was used rather than a more usual two-equation model of turbulence that relies on accurate wall function representation. The practical necessity to run in parallel with the experimental programme also limited the size of the mesh used. As with all free surface tracking algorithms, the minimum cell size determines the time step size for the stable simulations. Although the CDM method is implicit, allowing the time step to exceed the cell CFL limit, accuracy is then affected. With these restrictions, turnaround time for a complete tilt-casting cycle was possible within 24 h.As stated earlier, the feeder is necessary to minimise the solidification shrinkage porosity in the blade root. Two alternative designs have been considered: a cubic feeder with a volume to cooling surface area ratio of 14.5 mm, and a cylindrical feeder designed with better consideration of fluid dynamics during mould filling and which had a slightly lower volume to area ratio of 13.8 mm.4.2. Initial and boundary conditionsThe choice of parameters for the calculations was based on the experiments [16]. The properties of the materials used in the calculations are listed in Table 1. The initial conditions (the same as in the trials) and boundary conditions of the calculations are shown in Table 2.Table 1.Properties of the materials in this study.Ti–46Al–8Ta alloy MouldDensity (kg/m3) 5000 2200Thermal conductivity (W/(m K)) 21.6 1.6Specific heat (J/(kg K)) 1000 1000Viscosity (kg/(m s)) 0.5 ×10−60.1Liquidus temperature (°C) 1612 –Solidus temperature (°C) 1537 –Latent heat (J/kg) 355,000 100,0004.3. Tilt cycleThe molten metal in the ISM crucible is poured via the basin/feeder into the mould by rotating the assembly. A parabolic programmed cycle [16] is employed to complete the castingprocess with a total filling time of 6 s. The carefully designed cycle includes a fast rotation speed at the early stage of the mould filling to transfer the molten metal into the basin/feeder, a subsequent deceleration to a nearly zero velocity to allow most of the metal to fill the mould horizontally and to avoid forming a back wave and surface turbulence, and then the rapid completion of the filling to reduce the heat loss to the mould wall.5. Computing requirementsThe results presented here have been obtained using an Inter (R) Xeon (R) CPU E5520 2.27 GHz, 23.9 GB of RAM. For a typical mesh of 30,000 finite volume cells, each full tilt-casting simulation (real time 6 s) took approximately 15 h and 1200 time steps to complete. The CDM algorithm uses a fixed time step of 0.005 s which is at least five times larger than that used in conventional methods such as Van Leer or Donor–Acceptor. Similar computations carried out with the alternative Donor–Acceptor algorithm took typically one week to complete.The speed of execution and stability of the CDM method does not necessarily compromise accuracy. This can be demonstrated in the classic collapsing column benchmark experiment of Martin and Moyce [18] shown schematically in Fig. 3. A rectangular water column with a height of 2 m and a width of 1 m is initially confined between two vertical walls in hydrostatic equilibrium. Air is present as the outer medium. Once the confining wall is removed, the water column collapses on to the plane y = 0 under gravity and spreads out along the x direction.Fig. 3. Configuration of water column collapsing experiment.View thumbnail images The experiment was designed specifically so that it could be modelled computationally in two dimensions. Therefore, a 2D domain was used meshed into 880 cells (40 × 22).The comparison between the numerical result with CDM, the Van Leer and the popular Donor–Acceptor algorithm against the experimental data is presented in Fig. 4, where the horizontal extent of the water front and the residual height of the water column are plotted as functions of elapsed time. It can be seen that there is generally good agreement between the numerical results and the experimental data. However, although the three numerical methods match each other perfectly, there is some disagreement against the experiment when the non-dimensional time t* is greater than 1.4. It is concluded that in terms of accuracy, CDM is at least as good as the alternative explicit techniques which have been in widespread use for many years.Fig. 4. Validation of the CDM method and comparisons of the CDM against Van Leer, and donor acceptor for (a) the front position and (b) the residual height of the collapsing water column experiment of Martin and Moyce [18].As mentioned above, a feature of the CDM method is that the discretization of the free surface equation is made in a stable, fully implicit scheme which makes the computations an order of magnitude faster. Table 3 presents a comparison of CDM against the other two methods investigated, in terms of the computational efficiency. It is shown that CDM can be applied with a bigger time step than the other methods since CDM it is not limited by the Courant–Friedrichs–Levy (CFL) criterion. Furthermore, due to greater numerical stability, the number of iterations per time step is also reduced which makes the CDM simulation even faster. The first two columns in the table show that the time step for CDM can be ten times bigger than the others. The running time with the Van Leer total variation diminishing (TVD) scheme is 1.3 times longer than with CDM for the same time step, but the Van Leer scheme suffers from interface smearing. The running time of the most popular scheme for casting simulations, the donor acceptor method, is almost four times longer than that with CDM when the same time step is used. CDM is up to eight times faster (16 s vs. 132 s as shown underlined in Table 3) when the optimal time step for CDM is used.Table 3. Comparisons of the efficiency of CDM with others numerical methods.Δt1 = 0.1 s Δt1 = 0.05 s Δt1 = 0.01 sMethodN t (s) N t (s) N t (s)Van Leer Error Exceeds CFL limit 10 47Donor Acceptor Error Exceeds CFL limit 40 132CDM 20 16 15 17 5 34Notes: Δt = time step; t = running time; N = average number of iterations per time step.6. Simulations – results and discussion6.1. Effect of mould orientationCalculations with two orientations (Fig. 2a and b) for the assembly with the cubic feeder have been performed. Fig. 5 shows the mould filling progression as iso-surface plots of the free surface marker, at Ф = 0.5, at a filling time of 3.2 s. It is seen that in a design without consideration for flow behaviour, the metal is thrown into the cubic feeder in both cases in a turbulent state, becauseof the sudden change in cross-section. At any given time during filling, more metal enters the cubic feeder and less enters the blade in orientation 2, Fig. 5b, compared with orientation 1, Fig. 5a, leading to a restricted exit path for the escaping gas. For both orientations, the sudden drop at the connection between the feeder and the root of the blade leads to jetting and turbulence at the point where the metal flows from the feeder into the blade cavity.Comparison of mould filling with two orientations in contour plots of the free surface marker Ф = 0.5 at the interface, time = 3.2 s for a cubic feeder: (a) orientation 1: mould oriented at 30° to tilt axis; (b) orientation 2: long axis of the root perpendicular to the tilt plane.A later stage in the filling process is presented in Fig. 6 for the same two orientations, with the blades now filled with metal. Although both orientations display the same problems of gas mixing and turbulence caused by the two sudden steps in the feeder, it seems that orientation 1 leads to less gas mixing than orientation 2. Fig. 7 shows the 0.4 m-long turbine blade castings produced by the process. There is surface evidence of porosity at the connection between the feeder and the root of the blade on the concave sides, and this is worse for orientation 2 than for orientation 1. Radiography indicates the internal extent of this porosity. Although several factors are responsible for its formation, including the presence of a hot spot leading to an isolated liquid pool during solidification and subsequent shrinkage, the presence of trapped gas is a major contributorComparison of mould filling with two orientations in contour plots of the free surface marker Ф = 0.5 at the interface, time = 5.2 s for a cubic feeder: (a) orientation 1: mould oriented at 30° to tilt axis; (b) orientation 2: long axis of the root perpendicular to the tilt plane.Comparisons of the experimental results with two orientations: (a) orientation 1: mould oriented at 30° to tilt axis; (b) orientation 2: root axis perpendicular to the tilt plane.6.2. Effect of the mould design: cubic vs. cylindrical feederIn the above discussion, it was shown that the orientation of the blade relative to the tilt axis in Fig.2 is important, and that the sudden changes in cross-section with a cubic feeder lead to turbulent mixing of gas and liquid metal. In the following section, the effect of the feeder design on casting quality will be studied comparing two mould designs: one with a cylindrical feeder (Fig. 2c) and the other with a cubic feeder with the preferred orientation (Fig. 2a).Fig. 8 shows a comparison of the instantaneous free surface location at a filling time of 3.0 s. As can be seen, the metal is smoothly entering the blade cavity in the case of the cylindrical feeder. In contrast the metal is thrown into the cubic feeder because of the sudden change in the cross-section. The sudden drop at the connection between the feeder and the root of the bladeleads to jetting and turbulence when the metal flows from the feeder into the blade cavity. The comparison also shows that the filling of the blade with the cylindrical feeder is faster than with the cubic feeder. This phenomenon is demonstrated in Fig. 9 as well.The comparison of the mould filling with the two designs of feeder: iso-surface plots of the free surface marker Ф = 0.5 at time = 3.0 s: (a) cube feeder; (b) cylindrical feeder.Comparison of the mould filling with the two feeders: contour plots with the free surface marker Ф = 0.5 at the interface, time = 4.6 s: (a) cubic feeder; (b) cylindrical feeder.9 shows the flow progress at a later stage of the mould filling (rotation time of 4.6 s) for the two competing designs. It can be seen that the design with the cylindrical feeder and with the vertical orientation of the blade provides a better gas escape route back to the crucible (in addition to gas escaping through the vents in the mould) than the design with the cubic feeder. There are two flow restrictions in the cubic feeder design: one is the connection between the basin and the feeder and the other is the connection between the feeder and the root of the blade, both leading to a step change in cross-section. This geometric feature of the assembly causes the gas to be easily trapped in the upper corner of the root.Fig. 10 highlights the velocity vector field as the metal enters the mould in the cubic feeder design, Fig. 2a. It is seen that the metal is pushed back from the root of the blade (zoomed). The metal and the gas re-circulate in the cavity of the root. This recirculation will result in mixing of gas with the metal which presents a high risk of forming casting defects such as bubblesFig. 10. The computed velocity field and iso-surface (free surface marker Ф = 0.5 at the interface) time = 3.1 s for the cubic feeder.The computed velocity field in Fig. 11a illustrates that the gas is trapped and gas recirculation takes place in the cube feeder although some gas in the aerofoil and in the platform is slowly evacuated by the vents at the platform of the blade (zoomed). Gas recirculation leads to gas–metal mixing. This introduces a high risk of the formation of gas bubbles which are then blocked inside the casting if the superheat is not high enough to allow them time to float up before the casting solidifies. In Fig. 11b, it is shown that the cross-section at the connection of the basin with the cubic feeder is fully blocked by the metal coming from the crucible at a certain moment during the mould filling. This is the reason that gas recirculation appears in the cube feeder and the root of the blade. For the cylindrical feeder, the gas evacuation path is clear (Fig. 11c and d) and there is no danger of the gas being trapped in the upper corner of the root, especially since a vent is located at the top of the platform (see Fig. 2). Comparison of the computed velocity field and iso-surface (free surface marker Ф = 0.5 at the interface) time = 4.8 s。

模具毕业设计论文外文翻译

模具毕业设计论文外文翻译

Injection MoldingThe basic concept of injection molding revolves around the ability of a thermoplastic material to be softened by heat and to harden when cooled .In most operations ,granular material (the plastic resin) is fed into one end of the cylinder (usually through a feeding device known as a hopper ),heated, and softened(plasticized or plasticated),forced out the other end of the cylinder,while it is still in the form of a melt,through a nozzle into a relatively cool mold held closed under pressure.Here,the melt cools and hardens until fully set-up.The mold is then opened,the piece ejected,and the sequence repeated.Thus,the significant elements of an injection molding machine become :1)the way in which the melt is plasticized (softened) and forced into the mold (called the injection unit); 2)the system for opening the mold and closing it under pressure (called the clamping unit);3)the type of mold used;4)the machine controls.The part of an injection-molding machine,which converts a plastic material from a sold phase to homogeneous seni-liguid phase by raising its temperature .This unit maintains the material at a present temperature and force it through the injection unit nozzle into a mold .The plunger is a combination of the injection and plasticizing device in which a heating chamber is mounted between the plunger and mold. This chamber heats the plastic material by conduction .The plunger,on each storke; pushes unmelted plastic material into the chamber ,which in turn forces plastic melt at the front of the chamber out through the nozzleThe part of an injection molding machine in which the mold is mounted,and which provides the motion and force to open and close the mold and to hold the mold close with force during injection .This unit can also provide other features necessary for the effective functioning of the molding operation .Moving plate is the member of the clamping unit,which is moved toward a stationary member.the moving section of the mold is bolted to this moving plate .This member usually includes the ejector holesand moldmounting pattern of blot holes or “T” slots .Stationary plate is the fixed member of the clamping unit on which the stationary section of the mold is bolted .This member usually includes a mold-mounting pattern of boles or “T” slots.Tie rods are member of the clamping force actuating mechanism that serve as the tension member of the clamp when it is holding the mold closed.They also serve as a gutde member for the movable plate .Ejector is a provision in the clamping unit that actuates a mechanism within the mold to eject the molded part(s) from the mold .The ejection actuating force may be applied hydraulically or pneumatically by a cylinder(s) attached to the moving plate ,or mechanically by the opening storke of the moving plate.Methods of melting and injecting the plastic differ from one machine to another and are constantly being improred .couventional machines use a cylinder and piston to do both jobs .This method simplifies machine construction but makes control of injection temperatures and pressures an inherently difficult problem .Other machines use a plastcating extruder to melt the plastic and piston to inject it while some hare been designed to use a screw for both jobs :Nowadays,sixty percent o f the machines use a reciprocating screw,35% a plunger (concentrated in the smaller machine size),and 5%a screw pot.Many of the problems connected with in jection molding arises because the densities of polymers change so markedly with temperature and p ressure.Athigh temperatures,the density of a polymer is considerably cower than at room temperature,provided the pressure is the same.Therefore,if modls were filled at atmospheric pressure, “shrinkage”would make the molding deviate form the shape of the mold.To compensate for this poor effect, molds are filled at high pressure.The pressure compresses the polymer and allows more materials to flow into the mold,shrinkage is reduced and better quality moldings are produced.Cludes a mold-mounting pattern of bolt holes or “T” slots.Tie rods are members of the clamping force actuatingmachanism that serve as the tension members of clamp when it is holding the mold closed.Ejector is a provision in the claming unit that actuates a mechanism within the mold to eject themolded part(s) form the mold.The ejection actuating force may be applied hydraulically or pneumatically by a cylinder(s) attached to the moving plate,or mechanically by the opening stroke of the moving plate.The function of a mold is twofold :imparting the desired shape to the plasticized polymer and cooling the injection molded part.It is basically made up of two sets of components :the cavities and cores and the base in which the cavities and cores are mounted. The mold ,which contains one or more cavities,consists of two basic parts :(1) a stationary molds half one the side where the plastic is injected,(2)Amoving half on the closing or ejector side of the machine. The separation between the two mold halves is called the parting line.In some cases the cavity is partly in the stationary and partly in the moving section.The size and weight of the molded parts limit the number of cavities in the mold and also determine the machinery capacity required.The mold components and their functions are as following :(1)Mold Base-Hold cavity(cavities) in fixed ,correct position relative tomachine nozzle .(2)Guide Pins-Maintain Proper alignment of entry into mold intrior .(3)Sprue Bushing(sprue)-Provide means of entry into mold interior .(4)Runners-Conrey molten plastic from sprue to cavities .(5)Gates-Control flow into cavities.(6)Cavity(female) and Force(male)-Contorl the size,shape and surface of moldarticle.(7)Water Channels-Control the temperature of mold surfaces to chill plastic torigid state.(8)Side (actuated by came,gears or hydraulic cylinders)-Form sideholes,slots,undercuts and threaded sections.注射成型注射成型的基本概念是使热塑性材料在受热时熔融,冷却时硬化,在大部分加工中,粒状材料(即塑料树脂)从料筒的一端(通常通过一个叫做“料斗”的进料装置)送进,受热并熔融(即塑化或增塑),然后当材料还是溶体时,通过一个喷嘴从料筒的另一端挤到一个相对较冷的压和封闭的模子里。

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译文标题
模具设计和制造
原文标题
Mold design and manufacture
作者
Assist.Prof.Dr. A. YAYLA
译名
A·亚伊拉
国籍 manufacture
附件1:外文资料翻译译文 模具设计与制造 模具是制造业的重要工艺基础,在我国,模具制造属于专用设备制造业。中国虽然很早就开始制造模具和使用模具,但长期未形成产业。直到20世纪80年代后期,中国模具工业才驶入发展的快车道。近年,不仅国有模具企业有了很大发展,三资企业、乡镇(个体)模具企业的发展也相当迅速。 虽然中国模具工业发展迅速,但与需求相比,显然供不应求,其主要缺口集中于精密、大型、复杂、长寿命模具领域。由于在模具精度、寿命、制造周期及生产能力等方面,中国与国际平均水平和发达国家仍有较大差距,因此,每年需要大量进口模具。 中国模具产业除了要继续提高生产能力,今后更要着重于行业内部结构的调整和技术发展水平的提高。结构调整方面,主要是企业结构向专业化调整,产品结构向着中高档模具发展,向进出口结构的改进,中高档汽车覆盖件模具成形分析及结构改进、多功能复合模具和复合加工及激光技术在模具设计制造上的应用、高速切削、超精加工及抛光技术、信息化方向发展。 近年,模具行业结构调整和体制改革步伐加大,主要表现在,大型、精密、复杂、长寿命、中高档模具及模具标准件发展速度高于一般模具产品;塑料模和压铸模比例增大;专业模具厂数量及其生产能力增加;“三资”及私营企业发展迅速;股份制改造步伐加快等。从地区分布来看,以珠江三角洲和长江三角洲为中心的东南沿海地区发展快于中西部地区,南方的发展快于北方。目前发展最快、模具生产最为集中的省份是广东和浙江,江苏、上海、安徽和山东等地近几年也有较大发展。 虽然我国模具总量目前已达到相当规模,模具水平也有很大提高,但设计制造水平总体上落后于德、美、日、法、意等工业发达国家许多。当前存在的问题和差距主要表现在以下几方面: (1)总量供不应求 国内模具自配率只有70%左右。其中低档模具供过于求,中高档模具自配率只有50%左右。 (2)企业组织结构、产品结构、技术结构和进出口结构均不合理 我国模具生产厂中多数是自产自配的工模具车间(分厂),自产自配比例高达60%左右,而国外模具超过70%属商品模具。专业模具厂大多是“大而全”、“小而全”的组织形式,而国外大多是“小而专”、“小而精”。国内大型、精密、复杂、长寿命的模具占总量比例不足30%,而国外在50%以上。2004年,模具进出口之比为3.7:1,进出口相抵后的净进口额达13.2亿美元,为世界模具净进口量最大的国家。 (3)模具产品水平大大低于国际水平,生产周期却高于国际水平 产品水平低主要表现在模具的精度、型腔表面粗糙度、寿命及结构等方面。 (4)开发能力较差,经济效益欠佳 我国模具企业技术人员比例低,水平较低,且不重视产品开发,在市场中经常处于被动地位。我国每个模具职工平均年创造产值约合1万美元,国外模具工业发达国家大多是15~20万美元,有的高达25~30万美元,与之相对的是我国相当一部分模具企业还沿用过去作坊式管理,真正实现现代化企业管理的企业较少。 造成上述差距的原因很多,除了历史上模具作为产品长期未得到应有的重视,以及多数国有企业机制不能适应市场经济之外,还有下列几个原因: (1)国家对模具工业的政策支持力度还不够 虽然国家已经明确颁布了模具行业的产业政策,但配套政策少,执行力度弱。目前享受模具产品增值税的企业全国只有185家,大多数企业仍旧税负过重。模具企业进行技术改造引进设备要缴纳相当数量的税金,影响技术进步,而且民营企业贷款十分困难。 (2)人才严重不足,科研开发及技术攻关投入太少 模具行业是技术、资金、劳动密集的产业,随着时代的进步和技术的发展,掌握并且熟练运用新技术的人才异常短缺,高级模具钳工及企业管理人才也非常紧张。由于模具企业效益欠佳及对科研开发和技术攻关重视不够,科研单位和大专院校的眼睛盯着创收,导致模具行业在科研开发和技术攻关方面投入太少,致使模具技术发展步伐不大,进展不快。 (3)工艺装备水平低,且配套性不好,利用率低 近年来我国机床行业进步较快,已能提供比较成套的高精度加工设备,但与国外装备相比,仍有较大差距。虽然国内许多企业已引进许多国外先进设备,但总体的装备水平比国外许多企业低很多。由于体制和资金等方面的原因,引进设备不配套,设备与附件不配套现象十分普遍,设备利用率低的问题长期得不到较妥善的解决。 (4)专业化、标准化、商品化程度低,协作能力差 由于长期以来受“大而全”“小而全”影响,模具专业化水平低,专业分工不细致,商品化程度低。目前国内每年生产的模具,商品模具只占40%左右,其余为自产自用。模具企业之间协作不畅,难以完成较大规模的模具成套任务。模具标准化水平低,模具标准件使用覆盖率低也对模具质量、成本有较大影响,特别是对模具制造周期有很大影响。 (5)模具材料及模具相关技术落后 模具材料性能、质量和品种问题往往会影响模具质量、寿命及成本,国产模具钢与国外进口钢材相比有较大差距。塑料、板材、设备性能差,也直接影响模具水平的提高。 目前,我国经济仍处于高速发展阶段,国际上经济全球化发展趋势日趋明显,这为我国模具工业高速发展提供了良好的条件和机遇。一方面,国内模具市场将继续高速发展,另一方面,模具制造也逐渐向我国转移以及跨国集团到我国进行模具采购趋向也十分明显。因此,放眼未来,国际、国内的模具市场总体发展趋势前景看好,预计中国模具将在良好的市场环境下得到高速发展,我国不但会成为模具大国,而且一定逐步向模具制造强国的行列迈进。“十一五”期间,中国模具工业水平不仅在量和质的方面有很大提高,而且行业结构、产品水平、开发创新能力、企业的体制与机制以及技术进步的方面也会取得较大发展。 模具技术集合了机械、电子、化学、光学、材料、计算机、精密监测和信息网络等诸多学科,是一个综合性多学科的系统工程。模具技术的发展趋势主要是模具产品向着更大型、更精密、更复杂及更经济的方向发展,模具产品的技术含量不断提高,模具制造周期不断缩短,模具生产朝着信息化、无图化、精细化、自动化的方向发展,模具企业向着技术集成化、设备精良化、产批品牌化、管理信息化、经营国际化的方向发展。我国模具行业今后仍需提高的共性技术有: (1)建立在CAD/CAE平台上的先进模具设计技术,提高模具设计的现代化、信息化、智能化、标准化水平。 (2)建立在CAM/CAPP基础上的先进模具加工技术与先进制造技术相结合,提高模具加工的自动化水平与生产效率。 (3)模具生产企业的信息化管理技术。例如PDM(产品数据管理)、ERP(企业资源管理)、MIS(模具制造管理信息系统)及INTERMET平台等信息网络技术的应用、推广及发展。 (4)高速、高精、复合模具加工技术的研究与应用。例如超精冲压模具制造技术、精密塑料和压铸模具制造技术等。 (5)提高模具生产效率、降低成本和缩短模具生产周期的各种快速经济模具制造技术。 (6)先进制造技术的应用。例如热流道技术、气辅技术、虚拟技术、纳米技术、高速扫描技术、逆向工程、并行工程等技术在模具研究、开发、加工过程中的应用 (7)原材料在模具中成形的仿真技术。 (8)先进的模具加工和专有设备的研究与开发。 (9)模具及模具标准件、重要辅件的标准化技术。 (10)模具及其制品的检测技术。 (11)优质、新型模具材料的研究与开发及其正确应用。 (12)模具生产企业的现代化管理技术。 模具行业在“十一五”期间需要解决的重点关键技术应是模具信息化、数字化技术和精密、超精、高速、高效制造技术方面的突破。 随着国民经济总量和工业产品技术的不断发展,各行各业对模具的需求量越来越大,技术要求也越来越高。虽然模具种类繁多,但其发展重点应该是既能满足大量需要,又有较高技术含量,特别是目前国内尚不能自给,需大量进口的模具和能代表发展方向的大型、精密、复杂、长寿命模具。模具标准件的种类、数量、水平、生产集中度等对整个模具行业的发展有重大影响。因此,一些重要的模具标准件也必须重点发展,而且其发展速度应快于模具的发展速度,这样才能不断提高我国模具标准化水平,从而提高模具质量,缩短模具生产周期,降低成本。由于我国的模具产品在国际市场上占有较大的价格优势,因此对于出口前景好的模具产品也应作为重点来发展。根据上述需要量大、技术含量高、代表发展方向、出口前景好的原则选择重点发展产品,而且所选产品必须目前已有一定技术基础,属于有条件、有可能发展起来的产品。
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