注塑模外文资料
- 格式:doc
- 大小:28.00 KB
- 文档页数:4
外文翻译及原文(文档含英文原文和中文翻译)【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 and 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 machine selection, 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. The manufacturing process and involving moulds must be designed after passing through the appearance evaluation and the structure optimization of the product design. Designers face a hugenumber 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 design tools 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. AtHewlett-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 aspossible.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 the 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 Engi neering , V ol.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。
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。
塑料注射成型外文文献翻译、中英文翻译、外文翻译外文翻译原文: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 temperaturevariations, 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 theskin 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, forexample, 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. T oday 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 t o 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 ofengineering 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 andusing 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 flowsspontaneously 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。
Journal of Materials Processing Technology187–188 (2007) 690–693Adaptive system for electrically driven thermoregulationof moulds for injection mouldingB.Nardin a,∗,B.ˇZagar a,∗,A.Glojek a,D.Kriˇz aj ba TECOS,Tool and Die Development Centre of Slovenia,Kidriˇc eva Cesta25,3000Celje,Sloveniab Faculty of Electrical Engineering,Ljubljana,SloveniaAbstractOne of the basic problems in the development and production process of moulds for injection moulding is the control of temperature con-ditions in the mould.Precise study of thermodynamic processes in moulds showed,that heat exchange can be manipulated by thermoelectrical means.Such system upgrades conventional cooling systems within the mould or can be a stand alone application for heat manipulation within it.In the paper,the authors will present results of the research project,which was carried out in three phases and its results are patented in A686\2006 patent.The testing stage,the prototype stage and the industrialization phase will be presented.The main results of the project were total and rapid on-line thermoregulation of the mould over the cycle time and overall influence on quality of plastic product with emphasis on deformation control.Presented application can present a milestone in thefield of mould temperature and product quality control during the injection moulding process.© 2006 Elsevier B.V. All rights reserved.Keywords:Injection moulding;Mould cooling;Thermoelectric modules;FEM simulations1.Introduction,definition of problemDevelopment of technology of cooling moulds via thermo-electrical(TEM)means derives out of the industrial praxis and problems,i.e.at design,tool making and exploitation of tools. Current cooling technologies have technological limitations. Their limitations can be located and predicted in advance with finite element analyses(FEA)simulation packages but not com-pletely avoided.Results of a diverse state of the art analyses revealed that all existing cooling systems do not provide con-trollable heat transfer capabilities adequate tofit into demand-ing technological windows of current polymer processing technologies.Polymer processing is nowadays limited(in term of short-ening the production cycle time and within that reducing costs) only with heat capacity manipulation capabilities.Other produc-tion optimization capabilities are already driven to mechanical and polymer processing limitations[3].∗Corresponding authors.Tel.:+3863490920;fax:+38634264612.E-mail address:Blaz.Nardin@tecos.si(B.Nardin).1.1.Thermal processes in injection moulding plastic processingPlastic processing is based on heat transfer between plastic material and mould cavity.Within calculation of heat transfer one should consider two major facts:first is all used energy which is based onfirst law of thermodynamics—law of energy conservation[1],second is velocity of heat transfer.Basic task at heat transfer analyses is temperature calculation over time and its distribution inside studied system.That last depends on velocity of heat transfer between the system and surroundings and velocity of heat transfer inside the system.Heat transfer can be based as heat conduction,convection and radiation[1].1.2.Cooling timeComplete injection moulding process cycle comprises of mould closing phase,injection of melt into cavity,packing pres-sure phase for compensating shrinkage effect,cooling phase, mould opening phase and part ejection phase.In most cases,the longest time of all phases described above is cooling time.Cooling time in injection moulding process is defined as time needed to cool down the plastic part down to ejection temperature[1].0924-0136/$–see front matter© 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.jmatprotec.2006.11.052B.Nardin et al./Journal of Materials Processing Technology 187–188 (2007) 690–693691Fig.1.Mould temperature variation across one cycle[2].The main aim of a cooling process is to lower additional cooling time which is theoretically needless;in praxis,it extends from45up to67%of the whole cycle time[1,4].From literature and experiments[1,4],it can be seen,that the mould temperature has enormous influence on the ejection time and therefore the cooling time(costs).Injection moulding process is a cyclic process where mould temperature varies as shown in Fig.1where temperature varies from average value through whole cycle time.2.Cooling technology for plastic injection mouldsAs it was already described,there are already several differ-ent technologies,enabling the users to cool the moulds[5].The most conventional is the method with the drilling technology, i.e.producing holes in the mould.Through these holes(cooling lines),the cooling media isflowing,removing the generated and accumulated heat from the mould[1,2].It is also very convenient to build in different materials,with different thermal conductiv-ity with the aim to enhance control over temperature conditions in the mould.Such approaches are so called passive approaches towards the mould temperature control.The challenging task is to make an active system,which can alter the thermal conditions,regarding to the desired aspects, like product quality or cycles time.One of such approaches is integrating thermal electrical modules(TEM),which can alter the thermal conditions in the mould,regarding the desired prop-erties.With such approach,the one can control the heat transfer with the time and space variable,what means,that the temper-ature can be regulated throughout the injection moulding cycle, independent of the position in the mould.The heat control is done by the control unit,where the input variables are received from the manual input or the input from the injection moulding simulation.With the output values,the control unit monitors the TEM module behaviour.2.1.Thermoelectric modules(TEM)For the needs of the thermal manipulation,the TEM module was integrated into mould.Interaction between the heat and elec-trical variables for heat exchange is based on the Peltier effect. The phenomenon of Peltier effect is well known,but it wasuntilFig.2.TEM block diagram.now never used in the injection moulding applications.TEM module(see Fig.2)is a device composed of properly arranged pairs of P and N type semiconductors that are positioned between two ceramic plates forming the hot and the cold thermoelectric cooler sites.Power of a heat transfer can be easily controlled through the magnitude and the polarity of the supplied electric current.2.2.Application for mould coolingThe main idea of the application is inserting TEM module into walls of the mould cavity serving as a primary heat transfer unit.Such basic assembly can be seen in Fig.3.Secondary heat transfer is realized via conventionalfluid cooling system that allows heatflows in and out from mould cavity thermodynamic system.Device presented in Fig.3comprises of thermoelectric modules(A)that enable primarily heat transfer from or to tem-perature controllable surface of mould cavity(B).Secondary heat transfer is enabled via cooling channels(C)that deliver constant temperature conditions inside the mould.Thermoelec-tric modules(A)operate as heat pump and as such manipulate with heat derived to or from the mould byfluid cooling sys-tem(C).System for secondary heat manipulation with cooling channels work as heat exchanger.To reduce heat capacity of controllable area thermal insulation(D)is installed between the mould cavity(F)and the mould structure plates(E).Fig.3.Structure of TEM cooling assembly.692 B.Nardin et al./Journal of Materials ProcessingTechnology 187–188 (2007) 690–693Fig.4.Structure for temperature detection and regulation.The whole application consists of TEM modules,a temper-ature sensor and an electronic unit that controls the complete system.The system is described in Fig.4and comprises of an input unit(input interface)and a supply unit(unit for electronic and power electronic supply—H bridge unit).The input and supply units with the temperature sensor loop information are attached to a control unit that acts as an exe-cution unit trying to impose predefined temperate/time/position ing the Peltier effect,the unit can be used for heating or cooling purposes.The secondary heat removal is realized viafluid cooling media seen as heat exchanger in Fig.4.That unit is based on current cooling technologies and serves as a sink or a source of a heat.This enables complete control of processes in terms of temperature,time and position through the whole cycle. Furthermore,it allows various temperature/time/position pro-files within the cycle also for starting and ending procedures. Described technology can be used for various industrial and research purposes where precise temperature/time/position con-trol is required.The presented systems in Figs.3and4were analysed from the theoretical,as well as the practical point of view.The theoretical aspect was analysed by the FEM simulations,while the practical one by the development and the implementation of the prototype into real application testing.3.FEM analysis of mould coolingCurrent development of designing moulds for injection moulding comprises of several phases[3].Among them is also design and optimization of a cooling system.This is nowa-days performed by simulations using customized FEM packages (Moldflow[4])that can predict cooling system capabilities and especially its influence on plastic.With such simulations,mould designers gather information on product rheology and deforma-tion due to shrinkage as ell as production time cycle information.This thermal information is usually accurate but can still be unreliable in cases of insufficient rheological material informa-tion.For the high quality input for the thermal regulation of TEM,it is needed to get a picture about the temperature distri-bution during the cycle time and throughout the mould surface and throughout the mould thickness.Therefore,different process simulations areneeded.Fig.5.Cross-section of a prototype in FEM environment.3.1.Physical model,FEM analysisImplementation of FEM analyses into development project was done due to authors’long experiences with such packages [4]and possibility to perform different test in the virtual envi-ronment.Whole prototype cooling system was designed in FEM environment(see Fig.5)through which temperature distribution in each part of prototype cooling system and contacts between them were explored.For simulating physical properties inside a developed prototype,a simulation model was constructed using COMSOL Multiphysics software.Result was a FEM model identical to real prototype(see Fig.7)through which it was possible to compare and evaluate results.FEM model was explored in term of heat transfer physics taking into account two heat sources:a water exchanger with fluid physics and a thermoelectric module with heat transfer physics(only conduction and convection was analysed,radiation was ignored due to low relative temperature and therefore low impact on temperature).Boundary conditions for FEM analyses were set with the goal to achieve identical working conditions as in real test-ing.Surrounding air and the water exchanger were set at stable temperature of20◦C.Fig.6.Temperature distribution according to FEM analysis.B.Nardin et al./Journal of Materials Processing Technology 187–188 (2007) 690–693693Fig.7.Prototype in real environment.Results of the FEM analysis can be seen in Fig.6,i.e.temper-ature distribution through the simulation area shown in Fig.5. Fig.6represents steady state analysis which was very accurate in comparison to prototype tests.In order to simulate the time response also the transient simulation was performed,showing very positive results for future work.It was possible to achieve a temperature difference of200◦C in a short period of time(5s), what could cause several problems in the TEM structure.Those problems were solved by several solutions,such as adequate mounting,choosing appropriate TEM material and applying intelligent electronic regulation.boratory testingAs it was already described,the prototype was produced and tested(see Fig.7).The results are showing,that the set assump-tions were confirmed.With the TEM module it is possible to control the temperature distribution on different parts of the mould throughout the cycle time.With the laboratory tests,it was proven,that the heat manipulation can be practically regu-lated with TEM modules.The test were made in the laboratory, simulating the real industrial environment,with the injection moulding machine Krauss Maffei KM60C,temperature sen-sors,infrared cameras and the prototype TEM modules.The temperature response in1.8s varied form+5up to80◦C,what represents a wide area for the heat control within the injection moulding cycle.4.ConclusionsUse of thermoelectric module with its straightforward con-nection between the input and output relations represents a milestone in cooling applications.Its introduction into moulds for injection moulding with its problematic cooling construction and problematic processing of precise and high quality plastic parts represents high expectations.The authors were assuming that the use of the Peltier effect can be used for the temperature control in moulds for injection moulding.With the approach based on the simulation work and the real production of laboratory equipment proved,the assump-tions were confirmed.Simulation results showed a wide area of possible application of TEM module in the injection moulding process.With mentioned functionality of a temperature profile across cycle time,injection moulding process can be fully controlled. Industrial problems,such as uniform cooling of problematic A class surfaces and its consequence of plastic part appear-ance can be solved.Problems offilling thin long walls can be solved with overheating some surfaces at injection time.Further-more,with such application control over rheological properties of plastic materials can be gained.With the proper thermal regulation of TEM it was possible even to control the melt flow in the mould,during thefilling stage of the mould cav-ity.This is done with the appropriate temperature distribution of the mould(higher temperature on the thin walled parts of the product).With the application of TEM module,it is possible to signif-icantly reduce the cycle time in the injection moulding process. The limits of possible time reduction lies in the frame of10–25% of additional cooling time,describe in Section1.2.With the application of TEM module it is possible to actively control the warping of the product and to regulate the amount of product warpage in the way to achieve required product tol-erances.The presented TEM module cooling application for injection moulding process is a matter of priority note for the patent,held and owned by TECOS.References[1]I.ˇCati´c,Izmjena topline u kalupima za injekcijsko preˇs anje plastomera,Druˇs tvo plastiˇc ara i gumaraca,Zagreb,1985.[2]I.ˇCati´c,F.Johannaber,Injekcijsko preˇs anje polimera i ostalih materiala,Druˇs tvo za plastiku i gumu,Biblioteka polimerstvo,Zagreb,2004.[3]B.Nardin,K.Kuzman,Z.Kampuˇs,Injection moulding simulation resultsas an input to the injection moulding process,in:AFDM2002:The Sec-ond International Conference on Advanced Forming and Die Manufacturing Technology,Pusan,Korea,2002.[4]TECOS,Slovenian Tool and Die Development Centre,Moldflow SimulationProjects1996–2006.[5]S.C.Chen,et al.,Rapid mold surface heating/cooling using electromag-netic induction technology:ANTEC2004,Conference CD-ROM,Chicago, Illinois,16–20May,2004.。
模具塑料注射成型外文翻译外文文献英文文献XXXThere are many different processing methods used to convert plastic pellets。
powders。
and liquids into final products。
Plastic materials XXX。
thermoplastic materials XXX。
XXX require other methods。
It is XXX.XXX。
It is also the oldest method。
Suddenly。
XXX account for 30% of all XXX suitable for mass n。
when raw materials XXX in a single step of n。
In most cases。
n machiningis not required for such products。
The us products produced include toys。
automotive parts。
household items。
and electronic consumer goods.Because plastic n molds have many variable nships。
it is a complex and us processing process。
The success of XXX appropriate steps。
but on the XXX。
which leads to the n of XXX。
barrel temperature changes。
XXX ns can help ce tolerances。
ce defect rates。
and increase product quality.XXX operator is to produce products that e first-rate products in the shortest time。
模具外文翻译外文文献英文文献注塑模The Injection Molding1、The injection moldingInjection molding is principally used for the production of the thermoplastic parts,although some progress has been made in developing a method for injection molding some thermosetting materials.The problem of injection a method plastic into a mold cavity from a reservoir of melted material has been extremely difficult to solve for thermosetting plastic which cure and harden under such conditions within a few minutes.The principle of injection molding is quite similar to that of die-casting.The process consists of feeding a plastic compound in powered or granular form from a hopper through metering and melting stages and then injecting it into a mold.After a brief cooling period,the mold is opened and the solidified part ejected.Injection-molding machine operation.The advantage of injection molding are:(ⅰ)a high molding speed adapter for mass production is possible;(ⅱ)there is a wide choice of thermoplastic materials providing a variety of useful properties;(ⅲ)it is possible to mold threads,undercuts,side holes,and large thin section.2、The injection-molding machineSeveral methods are used to force or inject the melted plastic into the mold.The most commonly used system in the larger machines is the in-line reciprocating screw,as shown in Figure 2-1.The screw acts as a combination injection and plasticizing unit.As the plastic is fed to the rotating screw,it passes through three zones as shown:feed,compression,and metering.After the feed zone,the screw-flight depth is gradually reduced,force theplastic to compress.The work is converted to heat by conduction from the barrel surface.As the chamber in front of the screw becomes filled,it forces the screw back,tripping a limit switch that activates a hydraulic cylinder that forces the screw forward and injects the fluid plastic into the closed mold.An antiflowback valve presents plastic under pressure from escaping back into the screw flight.The clamping force that a machine is capable of exerting is part of the size designation and is measured in tons.A rule-of-thumb can be used to determine the tonnage required for a particular job.It is based on two tons of clamp force per square inch of projected area.If the flow pattern is difficult and the parts are thin,this may have to go to three or four tons.Many reciprocating-screw machines are capable of handing thermosetting plastic materials.Previously these materials were handled by compression or transfer molding.Thermosetting materials cure or polymerize in the mold and are ejected hot in the range of 375°C~410°C.T hermosetting parts must be allowed to cool in the mold in order or remove them without distortion. Thus thermosetting cycles can be faster.Of course the mold must be heated rather than chilled,as with thermoplastics.3、Basic Underfeed MouldA simple mould of this type is shown in Figure3-1,and the description of the design and the opening sequence follows.The mould consists of three basic parts,namely:the moving half,the floating cavity plate and the feed plate respectively.The moving half consists of The moving mould plate assembly,support block,backing plate,ejector assembly and the pin ejection system.Thus the moving half in this design is identical with the moving half of basic moulds.The floating cavity plate,which may be of the integer or insert-bolster design,is located on substantial guide pillars(not shown)fitted in the feed plate.These guide pillars must be of sufficient length to support the floating cavity plate over its full movement and still project to perform the function of alignment between the cavity and core when the mould is being closed.Guide bushes are fitted into the moving mould plate and the floating cavity plate respectively.The maximum movement of the floating cavity plate is controlled by stop or similar device.The moving mould plate is suitably bored to provide a clearance for the stop bolt assembly.The stop bolts must be long enough to provide sufficient space between the feed plate and the floating cavity plate for easy removal of the feed system.The minimum space provide for should be 65mm just sufficient for an operator to remove the feed system by hand if necessary.The desire operating sequence is for the first daylight to occur between the floating cavity plate.This ensures the sprue is pulled from the sprue bush immediately the mouldis opened.T o achieve this sequence,springs may be incorporated between the feed plate and the floating cavity plate.The springs should be strong enough to give an initial impetus to the floating cavity plate to ensure it moves away with the moving half.It is normal practice to mount the springs on the guide pillars(Figure3-2)and accommodate them in suitable pocket in the cavity plate.The major part of the feed system(runner and sprue)is accommodated in the feed plate to facilitate automatic operation,the runner should be of a trapezoidal form so that once it is pulled from the feed plate is can easily beextracted.Note that if a round runner is used,half the runner is formed in the floating cavity plate,where it would remain,and be prevented from falling or being wiped clear when the mould is opened.Now that we have considered the mould assembly in the some detail,we look at the cycle of operation for this type of mould.The impressions are filled via the feed system(Figure3-1(a))and after a suitable dwell period,the machine platens commence to open.A force is immediately exerted by the compression springs,which cause the floating cavity plate to move away with the moving half as previously discussed.The sprue is pulled from the sprue bush by the sprue puller.After the floating cavity plate has moved a predetermined distance,it is arrested by the stop bolts.The moving half continues to move back and the moldings,having shrunk on to the cores,are withdrawn from the cavities.The pin gate breaks at its junction with the runner(Figure3-1(b)).The sprue puller,being attached to the moving half,is pulled through the floating cavity plate and thereby release the feed system which is then free to fall between the floating cavity plate and the feed plate.The moving half continues to move back until the ejector system is operated and the moldings are ejected (Figure3-1(c)).When the mould is closed,the respective plates are returned to their molding position and the cycle is repeated.4、Feed SystemIt is necessary to provide 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 thefeed system comprises a sprue,runner and gate.These terms applyequally to the flow-way itself,and to the molded material which is remove from the flow-way itself in the process of extracted the molding.A typical feed system for a four-impression,two plate-type mould is shown in Figure4-1.It is seen that the material passes through the sprue,main runner,branch runner and gate before entering the impression.As the temperature of molten plastic is lowered which going through the sprue and runner,the viscosity will rise;however,the viscosity is lowered by shear heat generated when going through the gate to fill the cavity.It is desirable to keep the distance that the material has to travel down to a minimum to reduce pressure and heat losses.It is for this reason that careful consideration must be given to the impression layout gate’s design.4.1.SprueA sprue is a channel through which to transfer molten plastic injected from the nozzle of the injector into the mold.It is a part of sprue bush,which is a separate part from the mold.4.2.RunnerA runner is a channel that guides molten plastic into the cavity of a mold.4.3.GateA gate is an entrance through which molten plastic enters the cavity.The gate has the following function: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.4.4.Cold slug wellThe purpose of the cold slug well,shown opposite the sprue,is theoretically to receive the material that has chilled at the front of nozzle during the cooling and ejection phase.Perhaps of greater importance is the fact that it provides position means whereby 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.5、EjectionA molding is formed in mould by injecting a plastic melt,under pressure,into animpression via a feed system.It must therefore be removed manually.Furthermore,all thermoplastic materials contract as they solidify,which means that the molding will shrink on to the core which forms it.This shrinkage makes the molding difficult to remove. Facilities are provided on the injection machine for automatic actuation of an ejector system,and this is situated behind the moving platen.Because of this,the mould’s ejector system will be most effectively operated if placed in the moving half of the mould,i.e. the half attached to the moving platen.We have stated previously that we need to eject the molding from the core and it therefore follows that the core,too,will most satisfactorily be located in the moving half.The ejector system in a mould will be discussed under three headings,namely:(ⅰ)the ejector grid;(ⅱ)the ejector plate assembly; and(ⅲ)the method of ejection.5.1、Ejector gridThe ejector grid(Figure5-1)is that part of the mould which supports the mould plate and provides a space into which theejector plate assembly can be fitted and operated.The grid normally consists of a back plate on to which is mounted a number of conveniently shaped “support blocks”.The ejector plate assembly is that part of the mould to which the ejector element is attached.The assembly is contained in a pocket,formed by the ejector grid,directly behind the mould plate.The assembly(Figure5-2)consists of an ejector plate,a retaining plate and an ejector rod.One end of this latter member is threaded and it is screwed into the ejector plate.In this particular design the ejector rod function not only as an actuating member but also as a method of guiding the assembly.Note that the parallel portion of the ejector rod passes through an ejector rod bush fitted in the back plate of the mould.5.2、Ejection techniquesWhen a molding cools,it contracts by an amount depending on the material being processed.For a molding which has no internal form,for example,a solid rectangular block,the molding will shrink away from the cavity walls,thereby permitting a simple ejection technique to be adopted.However,when the molding has internal form,the molding,as it cools,will shrink onto the core and some positive type of ejection is necessary.The designer has several ejection techniques from which to choose,but in general,the choice will be restricted depending upon the shape of the molding.The basic ejection techniques are as follows:(ⅰ)pin ejection(ⅱ)sleeve ejection(ⅲ)stripper plate ejection and(Ⅳ)air ejection.Figure 2-1aFigure 2-1bFigure 3-1Figure 3-2Figure 4-1aFigure 4-1bFigure 5-1Figure 5-2注塑模1、注塑模尽管成型某些热固性材料的方法取得了一定的进步,但注塑模主要(还是)用来生产热塑性塑件。
Injection molding die design is a crucial aspect of the manufacturing process to produce high-quality plastic products. Various technical references have been published over the years, providing valuable insights into the design principles, strategies, and best practices related to injection molding die design. Here are some key references that can be used as a starting point for further exploration:1.Injection Mold Design Engineering (David O. Kazmer, 2011) This bookprovides a comprehensive overview of injection mold design, covering topics such as mold geometry, gating systems, cooling and heating, ejector systems, and mold materials. It also discusses the analysis and optimization of molddesigns using computer-aided engineering tools.2.Injection Molds and Molding: A Practical Manual (Jiri Karasek, 2006)This practical manual offers a step-by-step guide to injection mold design and production. It covers various aspects of mold design, including cavity and core geometry, runner systems, venting, cooling, ejection, and mold materials. The book also addresses common design challenges and troubleshootingtechniques.3.Plastic Injection Molding: Manufacturing Process Fundamentals(Douglas M. Bryce and Charles A. Daniels, 2014) This reference provides an in-depth understanding of the injection molding process and its fundamentals. It discusses the principles of mold design, material selection, process parameters, molding defects, and mold maintenance. The book emphasizes the importance of considering the design-for-manufacturability aspect in mold design.4.Mold Design Using SolidWorks (Edward J. Bordin, 2010) Focused onmold design using SolidWorks software, this book provides practical insights into mold design methodology, including parting line creation, runner system design, cooling strategies, and mold analysis. It also covers advanced topicssuch as hot runner systems and side actions.5.Designing Injection Molds for Thermoplastics (H.T. Rowe, 2010) Thiscomprehensive reference addresses the design considerations specific tothermoplastic injection molds. It covers mold configuration, gating design,cooling strategies, shrinkage and warpage control, and mold materials. Thebook also includes case studies and practical tips for mold design optimization.6.Mold-Making Handbook (Kurtz Ersa Corporation, 2009) Thishandbook offers practical advice on mold design, construction, andmaintenance. It covers topics like mold steel selection, surface finishing, cavity design, cooling channels, ejection systems, and high-precision molding. Thereference provides insights into the latest developments in mold-makingtechnology.These references provide a solid foundation for understanding injection mold design principles, methodologies, and considerations. Additionally, industrypublications, research papers, and case studies can offer further insights into specific design aspects, material selection, and advanced techniques. It is important to consult multiple sources and stay updated with the latest trends and advancements in injection mold design to ensure efficient and robust manufacturing processes.。
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。
外文资料翻译系部:专业:姓名:学号:外文出处:dvanced English literacy course(用外文写)附件:指导老师评语签名:年月日第一篇译文(中文)2.3注射模2.3.1注射模塑注塑主要用于热塑性制件的生产,它也是最古老的塑料成型方式之一。
目前,注塑占所有塑料树脂消费的30%。
典型的注塑产品主要有杯子器具、容器、机架、工具手柄、旋钮(球形捏手)、电器和通讯部件(如电话接收器),玩具和铅管制造装置。
聚合物熔体因其较高的分子质量而具有很高的粘性;它们不能像金属一样在重力流的作用下直接被倒入模具中,而是需要在高压的作用下强行注入模具中。
因此当一个金属铸件的机械性能主要由模壁热传递的速率决定,这决定了最终铸件的晶粒度和纤维取向,也决定了注塑时熔体注入时的高压产生强大的剪切力是物料中分子取向的主要决定力量。
由此所知,成品的机械性能主要受注射条件和在模具中的冷却条件影响。
注塑已经被应用于热塑性塑料和热固性塑料、泡沫部分,而且也已经被改良用于生产反应注塑过程,在此过程中,一个热固树脂系统的两个组成部分在模具中同时被注射填充,然后迅速聚合。
然而大多数注塑被用热塑性塑料上,接下来的讨论就集中在这样的模具上。
典型的注塑周期或流程包括五个阶段(见图2-1):(1)注射或模具填充;(2)填充或压紧;(3)定型;(4)冷却;(5)零件顶出。
图2-1 注塑流程塑料芯块(或粉末)被装入进料斗,穿过一条在注射料筒中通过旋转螺杆的作用下塑料芯块(或粉末)被向前推进的通道。
螺杆的旋转迫使这些芯块在高压下对抗使它们受热融化的料筒加热壁。
加热温度在265至500华氏度之间。
随着压力增强,旋转螺杆被推向后压直到积累了足够的塑料能够发射。
注射活塞迫使熔融塑料从料筒,通过喷嘴、浇口和流道系统,最后进入模具型腔。
在注塑过程中,模具型腔被完全充满。
当塑料接触冰冷的模具表面,便迅速固化形成表层。
由于型芯还处于熔融状态,塑料流经型芯来完成模具的填充。
abrasive grinding 强力磨削abrasive 磨料的,研磨的absence 不在,缺席accesssory 附件accommodate 适应accordingly 因此,从而,相应地accuracy 精度,准确性actuate 开动(机器),驱动adequate 足够的adhesive 粘合剂adjacent 邻近的adopt 采用advance 进步advisable 可取的agitate 摇动a large extent 很大程度algorithm 算法align 定位,调准alignment 校直all-too-frequent 频繁allowance 容差,余量alternate 交替,轮流alternatively 做为选择,也许aluminiun 铝ample 充足的analysis 分析ancillary 补助的,副的angular 有角的annealing 退火aperture 孔applied loads 作用力appropriate 适当的arc 弧,弓形arise 出现,发生arrange 安排article 制品,产品ascertain 确定,查明assemble 组装attitude 态度auxiliary 辅助的avoid 避免axis 轴axle 轮轴,车轴alternative 替换物backup 备份batch 一批bearing 轴承,支座bed 床身behavior 性能bench-work 钳工工作bend 弯曲beneath 在•••下bin 仓,料架blank 坯料blank 冲裁,落料blanking 落料模blast 一阵(风)blemish 缺点,污点bolster 模座,垫板boring 镗削,镗孔bracket 支架brass 黄铜break down 破坏breakage 破坏brine 盐水brittle 易碎的buffer 缓冲器built-in 内装的bulging 凸肚burr 毛刺bush 衬套by far •••得多,最by means of 借助于boost 推进cabinet 橱柜call upon 要求carbide 碳化物carburzing 渗碳carriage 拖板,大拖板carry along 一起带走carry down over 从•••上取下carry out 完成case hardening 表面硬化case 壳,套cast steel 铸钢casting 铸造,铸件category 种类caution 警告,警示cavity and core plates 凹模和凸模板cavity 型腔,腔,洞centre-drilling 中心孔ceramic 陶瓷制品chain doted line 点划线channel 通道,信道characteristic 特性check 核算chip 切屑,铁屑chuck 卡盘chute 斜道circa 大约circlip (开口)簧环circuit 回路,环路circulate (使)循环clamp 夹紧clamp 压板clay 泥土clearance 间隙clip 切断,夹住cold hobbing 冷挤压cold slug well 冷料井collapse 崩塌,瓦解collapsible 可分解的combination 组合commence 开始,着手commence 开始commercial 商业的competitive 竞争的complementary 互补的complexity 复杂性complication 复杂化compression 压缩comprise 包含compromise 妥协,折衷concern with 关于concise 简明的,简练的confront 使面临connector 连接口,接头consequent 随之发生的,必然的console 控制台consume 消耗,占用consummate 使完善container 容器contingent 可能发生的CPU (central processing unit) 中央处理器conventional 常规的converge 集中于一点conversant 熟悉的conversion 换算,转换conveyer 运送装置coolant 冷却液coordinate (使)协调copy machine 仿形(加工)机床core 型芯,核心corresponding 相应的counteract 反作用,抵抗couple with 伴随contour 轮廓crack (使)破裂,裂纹critical 临界的cross-hatching 剖面线cross-section drawn 剖面图cross-slide 横向滑板CRT (cathoder-ray tube) 阴极射线管crush 压碎cryogenic 低温学的crystal 结晶状的cubic 立方的,立方体的cup (使)成杯状,引伸curable 可矫正的curvature 弧线curve 使弯曲cutter bit 刀头,刀片cyanide 氰化物complicated 复杂的dash 破折号daylight 板距decline 下落,下降,减少deform (使)变形demonstrate 证明depict 描述deposite 放置depression 凹穴descend 下降desirable 合适的detail 细节,详情deterioration 退化,恶化determine 决定diagrammmatic 图解的,图表的dictate 支配die 模具,冲模,凹模dielectric 电介质die-set 模架digital 数字式数字dimensional 尺寸的,空间的discharge 放电,卸下,排出discharge 卸下discrete 离散的,分立的dislodge 拉出,取出dissolution 结束distinct 不同的,显著的distort 扭曲distort (使)变形,扭曲distributed system 分布式系统dowel 销子dramaticlly 显著地drastic 激烈的draughting 绘图draughtsman 起草人drawing 制图drill press 钻床drum 鼓轮dual 双的,双重的ductility 延展性dynamic 动力的edge 边缘e.g.(exempli gratia) [拉]例如ejector 排出器ejector plate 顶出板ejector rob 顶杆elasticity 弹性electric dicharge machining 电火花加工electrode 电极electro-deposition 电铸elementary 基本的eliminate 消除,除去elongate (使)伸长,延长emerge 形成,显现emphasise 强调endeavour 尽力engagement 约束,接合enhance 提高,增强ensure 确保,保证erase 抹去,擦掉evaluation 评价,估价eventually 终于evolution 进展excecution 执行,完成execute 执行electrochemical machining 电化学加工exerte 施加experience 经验explosive 爆炸(性)的extend 伸展external 外部的extract 拔出extreme 极端extremely 非常地extremity 极端extrusion 挤压,挤出envisage 设想Fahrenheit 华氏温度fabricate 制作,制造flat-panel technology 平面(显示)技术facility 设备facing 端面车削fall within 属于,适合于fan 风扇far from 毫不,一点不,远非fatigue 疲劳feasible 可行的feature 特色,特征feed 进给feedback 反馈female 阴的,凹形的ferrule 套管file system 文件系统fitter 装配工,钳工fix 使固定,安装fixed half and moving half 定模和动模facilitate 帮助flexibility 适应性,柔性flexible 柔韧的flow mark 流动斑点follow-on tool 连续模foregoing 在前的,前面的foretell 预测,预示,预言forge 锻造forming 成型four screen quadrants 四屏幕象限fracture 破裂free from 免于gap 裂口,间隙gearbox 齿轮箱govern 统治,支配,管理grain 纹理graphic 图解的grasp 抓住grid 格子,网格grind 磨,磨削,研磨grinding 磨光,磨削grinding machine 磨床gripper 抓爪,夹具groove 凹槽guide bush 导套guide pillar 导柱guide pillars and bushes 导柱和导套handset 电话听筒hardness 硬度hardware 硬件headstock 床头箱,主轴箱hexagonal 六角形的,六角的hindrance 障碍,障碍物hob 滚刀,冲头hollow-ware 空心件horizontal 水平的hose 软管,水管hyperbolic 双曲线的i.e. (id est) [拉]也就是identical 同样的identify 确定,识别idle 空闲的immediately 正好,恰好impact 冲击impart 给予implement 实现impossibility 不可能impression 型腔in contact with 接触in terms of 依据inasmuch (as) co因为,由于inch-to-metric conversions 英公制转换inclinable 可倾斜的inclusion 内含物inconspicuous 不显眼的incorporate 合并,混合indentation 压痕indenter 压头independently 独自地,独立地inevitably 不可避免地inexpensive 便宜的inherently 固有的injection mould 注塑模injection 注射in-line-of-draw 直接脱模insert 嵌件inserted die 嵌入式凹模inspection 检查,监督installation 安装integration 集成intelligent 智能的intentinonally 加强地,集中地interface 界面internal 内部的interpolation 插值法investment casting 熔模铸造irregular 不规则的,无规律irrespective of 不论,不管irrespective 不顾的,不考虑的issue 发布,发出joint line 结合线kerosene 煤油keyboard 健盘knock 敲,敲打lance 切缝lathe 车床latitude 自由lay out 布置limitation 限度,限制,局限(性) local intelligence 局部智能locate 定位logic 逻辑longitudinal 纵向的longitudinally 纵向的look upon 视作,看待lubrication 润滑machine shop 车间machine table 工作台machining 加工made-to-measure 定做maintenance 维护,维修majority 多数make use of 利用male 阳的,凸形的malfunction 故障mandrel 心轴manifestation 表现,显示massiveness 厚实,大块measure 大小,度量microcomputer 微型计算机microns 微米microprocessor 微处理器mild steel 低碳钢milling machine 铣床mineral 矿物,矿产minimise 把减到最少,最小化minute 微小的mirror image 镜像mirror 镜子moderate 适度的modification 修改,修正modulus 系数mold 模,铸模mold 制模,造型monitor 监控monograph 专著more often than not 常常motivation 动机mould split line 模具分型线moulding 注塑件move away from 抛弃multi-imprssion mould 多型腔模narrow 狭窄的NC (numerical control) 数控nevertheless 然而,不过nonferrous 不含铁的,非铁的normally 通常地novice 新手,初学者nozzle 喷嘴,注口numerical 数字的objectionable 有异议的,讨厌的observe 观察obviously 明显地off-line 脱机的on-line 联机operational 操作的,运作的opportunity 时机,机会opposing 对立的,对面的opposite 反面optimization 最优化orient 确定方向orthodox 正统的,正规的overall 全面的,全部的overbend 过度弯曲overcome 克服,战胜overlaping 重叠overriding 主要的,占优势的opposite 对立的,对面的pack 包装package 包装pallet 货盘panel 面板paraffin 石蜡parallel 平行的penetration 穿透peripheral 外围的periphery 外围permit 许可,允许pessure casting 压力铸造pillar 柱子,导柱pin 销,栓,钉pin-point gate 针点式浇口piston 活塞plan view 主视图plasma 等离子plastic 塑料platen 压板plotter 绘图机plunge 翻孔plunge 投入plunger 柱塞pocket-size 袖珍portray 描绘pot 壶pour 灌,注practicable 行得通的preferable 更好的,更可取的preliminary 初步的,预备的press setter 装模工press 压,压床,冲床,压力机prevent 妨碍primarily 主要地procedure 步骤,方法,程序productivity 生产力profile 轮廓progressively 渐进地project 项目project 凸出projection 突出部分proper 本身的property 特性prototype 原形proximity 接近prudent 谨慎的punch 冲孔punch shapper tool 刨模机punch-cum-blanking die 凹凸模punched tape 穿孔带purchase 买,购买push back pin 回程杆pyrometer 高温计quality 质量quandrant 象限quantity 量,数量quench 淬火radial 放射状的ram 撞锤rapid 迅速的rapidly 迅速地raster 光栅raw 未加工的raw material 原材料ream 铰大reaming 扩孔,铰孔recall 记起,想起recede 收回,后退recess 凹槽,凹座,凹进处redundancy 过多re-entrant 凹入的refer 指,涉及,谈及reference 参照,参考refresh display 刷新显示register ring 定位环register 记录,显示,记数regrind 再磨研relative 相当的,比较的relay 继电器release 释放relegate 把降低到reliability 可靠性relief valves 安全阀relief 解除relieve 减轻,解除remainder 剩余物,其余部分removal 取出remove 切除,切削reposition 重新安排represent 代表,象征reputable 有名的,受尊敬的reservoir 容器,储存器resident 驻存的resist 抵抗resistance 阻力,抵抗resolution 分辨率respective 分别的,各自的respond 响应,作出反应responsibility 责任restrain 抑制restrict 限制,限定restriction 限制retain 保持,保留retaining plate 顶出固定板reveal 显示,展现reversal 反向right-angled 成直角的rigidity 钢度rod 杆,棒rotate (使)旋转rough machining 粗加工rough 粗略的routine 程序rubber 橡胶runner and gate systems 流道和浇口系统sand casting 砂型铸造satisfactorily 满意地saw 锯子scale 硬壳score 刻划scrap 废料,边角料,切屑screwcutting 切螺纹seal 密封section cutting plane 剖切面secure 固定secure 紧固,夹紧,固定segment 分割sensitive 敏感的sequence 次序sequential 相继的seriously 严重地servomechanism 伺服机构servomotor 伺服马达setter 安装者set-up 机构sever 切断severity 严重shaded 阴影的shank 柄shear 剪,切shot 注射shrink 收缩side sectional view 侧视图signal 信号similarity 类似simplicity 简单single-point cutting tool 单刃刀具situate 使位于,使处于slide 滑动,滑落slideway 导轨slot 槽slug 嵌条soak 浸,泡,均热software 软件solid 立体,固体solidify (使)凝固solidify (使)固化solution 溶液sophisiticated 尖端的,完善的sound 结实的,坚固的spark erosion 火花蚀刻spindle 主轴spline 花键split 侧向分型,分型spool 线轴springback 反弹spring-loaded 装弹簧的sprue bush 主流道衬套sprue puller 浇道拉杆square 使成方形Servomechanism Laboratoies 伺服机构实验室stage 阶段standardisation 标准化startling 令人吃惊的steadily 稳定地step-by-step 逐步stickiness 粘性stiffness 刚度stock 毛坯,坯料storage tube display 储存管显示storage 储存器straightforward 直接的strain 应变strength 强度stress 压力,应力stress-strain 应力--应变stretch 伸展strike 冲击stringent 严厉的stripper 推板stroke 冲程,行程structrural build-up 结构上形成的sub-base 垫板subject 使受到submerge 淹没subsequent 后来的subsequently 后来,随后substantial 实质的substitute 代替,替换subtract 减,减去suitable 合适的,适当的suitably 合适地sunk 下沉,下陷superior 上好的susceptible 易受影响的sweep away 扫过symmetrical 对称的synchronize 同步,同时发生tactile 触觉的,有触觉的tailstock 尾架tapered 锥形的tapping 攻丝technique 技术tempering 回火tendency 趋向,倾向tensile 拉力的,可拉伸的tension 拉紧,张紧terminal 终端机terminology 术语,用辞theoretically 理论地thereby 因此,从而thermoplastic 热塑性的thermoplastic 热塑性塑料thermoset 热固性thoroughly 十分地,彻底地thread pitch 螺距thread 螺纹thrown up 推上tilt 倾斜,翘起tolerance 公差two-plate mould 双板式注射模tong 火钳tonnage 吨位,总吨数tool point 刀锋tool room 工具车间toolholder 刀夹,工具柄toolmaker 模具制造者toolpost grinder 工具磨床toolpost 刀架torsional 扭转的toughness 韧性trace 追踪transverse 横向的tray 盘,盘子,蝶treatment 处理tremendous 惊人的,巨大的trend 趋势trigger stop 始用挡料销tungsten 钨turning 车削twist 扭曲,扭转tracer-controlled milling machine 仿形铣床ultimately 终于undercut moulding 侧向分型模undercut 侧向分型undercut 底切underfeed 底部进料的undergo 经受underside 下面,下侧undue 不适当的,过度的uniform 统一的,一致的utilize 利用Utopian 乌托邦的,理想化的valve 阀vaporize 汽化vaporize (使)蒸发variation 变化various 不同的,各种的vector feedrate computation 向量进刀速率计算vee 字形velocity 速度versatile 多才多艺的,万用的vertical 垂直的via prep经,通过vicinity 附近viewpoint 观点wander 偏离方向warp 翘曲washer 垫圈wear 磨损well line 结合线whereupon 于是winding 绕,卷with respect to 相对于withstand 经受,经得起work 工件workstage 工序wrinkle 皱纹使皱yield 生产zoom 图象电子放大。
介绍了注塑模具制造特点和新兴注射成型技术对模具制造的新要求,阐述了注塑模具的快速成型技术、高速切削加工、精密制造技术和新兴模具材料,对以上四者的发展现状进行了综合评述,分析了注塑模具制造技术中的几个关键问题。
关键词:先进制造;注塑模具;精密制造;高速切削技术Key Technology Problems in Injecting Mould Advanced MakingAbstract: This text introduced the injecting plastics mould making characteristicand new injecting demand to the mould of new shaping technology,expanded mould plastics rapid shaping technique of mould , cut process,accurate manufacturing technology and new developing mould material,surveyed the current situation of the development of four,analyzed mould plastics several key problems of mould manufacturing technology. Key words: advanced making; injecting mould; make accurately; high-speed cutting technology前言模具行业是制造业的重要组成部分,具有广阔的市场前景。
目前全世界的模具年产值在650亿美元左右,我国的模具年产值为40亿美元左右,据估计到2005年我国模具产值将达到460亿人民币。
目前我国一般模具的30%,中高档模具的一半以上还依赖进口(其中注塑模占有很大的比例)。
由此可见,模具(特别是注塑模具)制造业的落后在某种程度上已经成为阻滞我国制造业发展的瓶颈所在。
开发和引进先进制造技术是改变我国注塑模具制造业相对落后和市场需求快速增长的重要途径。
先进制造技术是制造业不断吸收信息技术和现代管理技术的成果,并将其应用于产品的设计、加工、检测、管理、销售、使用、服务乃至回收的制造全过程,以实现优质、高效、低耗、清洁、灵活生产,提高对动态多变的市场的适应能力和竞争力的制造技术的总称。
先进制造业正在急剧地改变着传统制造业的产品结构和生产模式,注塑模具制造业也不例外。
1 注塑模具制造的特点⑴型腔及型芯呈立体型面。
塑件的外部和内部形状是由型腔和型芯直接成型的,这些复杂的立体型面加工难度比较大,特别是型腔的盲孔型内成型表面加工,如果采用传统的加工方法,不仅要求工人技术水平高、辅助工夹具多、刀具多,而且加工的周期长。
⑵精度和表面质量要求高,使用寿命要求长。
目前一般塑件的尺寸精度要求为IT6~7,表面粗糙度Ra0.2~0.1μm,相应的注塑模具零件的尺寸精度要求达到IT5~6,表面粗糙度Ra 0.1μm以下。
激光盘记录面的粗糙度要达到镜面加工的水平的0.02~0.01μm这就要求模具的表面粗糙度达到0.01μm以下。
长寿命注塑模具对于提高高效率和降低成本是很必要的,目前注塑模具的使用寿命一般要求100万次以上。
精密注塑模要用刚度大的模架,增加模板的厚度,增加支承柱或锥形定位元件以防止模具受压力后产生变形,有时内压可以达到1 00MPa。
顶出装置是影响制品变形和尺寸精度的重要因素,因此应该选择最佳的顶出点,以使各处脱模均匀。
高精度注塑模具在结构上多数采用镶拼或全拼结构,这要求模具零部件的加工精度、互换性均大为提高。
⑶工艺流程长,制造时间紧。
对于注塑件而言,大多是与其它零部件配套组成完整的产品,而且在很多的情况下都是在其它部件已经完成,急切等待注塑件的配套上市。
因为对制品的形状或尺寸精度要求很高,加之由于树脂材料的特性各异,模具制造完成后,还需要反复地试模与修正,使开发和交货的时间非常紧张。
⑷异地设计、异地制造。
模具制造不是最终目的,而是由用户提出最终制品设计,模具制造厂家根据用户的要求,设计制造模具而且在大多数情况下,制品的注射生产也在别的厂家。
这样就造成了产品的设计、模具设计制造和制品的生产异地进行的情况。
⑸专业分工,动态组合。
模具生产批量小,一般属于单件的生产,但是模具需要很多的标准件,大到模架,小到顶针,这些不能也不可能只由一个厂家单独完成,且制造工艺复杂,普通设备和数控设备使用极不均衡。
2 模具制造技术的发展方向基于以上模具制造的五个特点,对现代模具制造业提出了相应的要求。
当前模具制造的发展方向主要表现为以下五个方面:2.1从一般的机加工方法,发展至采用光机电相结合的数控电火花成形、数控电火花线切割以及各种特殊加工相结合,例如电铸成形、粉末冶金成形、精密铸造成形、激光加工等。
从而可以加工出复杂的型腔和型芯,以及保证较高的加工精度要求。
目前慢走丝线切割和电火花放电加工精度要求。
目前慢走丝线切割和电火花放电加工精度可达到±1.5μm,加工表面粗糙度可达到Ra0.004μm,基本上达到了精面要求。
2.2先进的技术支持条件。
模具的服务对象主要是电器、汽车厂家,产品的更新换代快,而且模具的设计已经从二维发展为三维,实现了可视化设计,不但可以立体、直观地再现尚未加工出的模具体,真正实现了CAD/CAM一体化,而且三维设计解决了二维设计难于解决的一些问题,诸如:干涉检查、模拟装配等。
2.3模具快速制造技术。
当前快速制造有三个发展方向:分别是基于并行工程的注塑模具快速制造、基于快速原型技术的注塑模具快速制造和高速切削技术。
2.3.1 基于并行工程的注塑模具快速制造这种生产方式。
是以注塑模具的标准化设计为基础的,它主要体现为经营管理、模具设计为基础的,它主要体现为经营管理、模具设计和模具制造的三个体系的标准化。
为了实现标准化,需要解决三项关键技术:一是统一数据库和文件传输格式;二是充分利用和开发Internet和Intranet,实现信息的集成和数据资源的共享;三是解决生产的组织、协调和专业分工,确定各个部门和层次的项目分解和利益分配的基准和算法。
2.3.2 基于快速原型技术的注塑模具快速制造。
直接从CAD模型生产工模具被认为是一种可以减少新产品成本和开发周期的重要的方法,近些年来,这种将CAD技术、快速成型(RP)和快速工模具制造(RT)等高新技术相结合,已经对传统的注塑模具的制造产生了重大的冲击。
CAD技术的应用在很大程度上代替了实物的评估和试验,减少了新产品研制过程中的迭代次数,从而加快了新产品的开发速度。
2.3.3 高速切削技术(High Speed Machining)的应用。
高速切削技术制造模具,具有切削效率高,可明显缩短机动加工时间,加工精度高,表面质量好,因此可大大缩短机械后加工、人工后加工和取样检验辅助工时等许多优点。
在某注塑模的高速铣削中,材料硬度为56~58HRC,原来采用电火花加工(EDM),每个零件需时90min,采用直径为12mm球头铣刀,主轴转速1500r/ min、工作台进给15 00r/ min进行高速加工,加工每个零件只需5min,工效提高了18倍。
今后,电火花成形加工应该主要针对一些尖角、窄槽、深小孔和过于复杂的型腔表面的精密加工。
高速成切削加工在发达国家的模具制造业中已经处于主流地位,据统计,目前有85%左右的模具电火花形加工工序已被高速加工所取代。
但是由于高速切削的一次性设备投资比较大,在国内,高速成切削与电火花加工还会在较长时间内并存。
模具的高速切削中对高速切削机床有下列技术要求:①主轴转速高,功率大;②机床的刚度好;③主轴转动和工作台直线运动都要有极高的加速度。
由于高速切削时产生的切削热和刀具的磨损比普通速度切削高很多,因此,高速刀具的配置十分重要,主要表现为:①刀具材料应硬度高、强度高、耐磨性好,韧度高、抗冲击能力强,热稳定和化学稳定性好;②必须精心选择刀具结构和精度、切削刃的几何参数,刀具与机床的连接方式广泛采用锥部与主轴端面同时接触的HSK空心刀柄,锥度为1:10,以确保高速运转刀具的安全和轴向加工精度。
③型腔的粗加工、半精加工和精加工一般采用球头铣刀,其直径应小于模具型腔曲面的最小曲率半径;而模具零件的平面的粗、精加工则可采用带转位刀片的端铣刀。
2.4 发展新的塑料模具材料及模具表面技术。
主要是发展易加工、抛光性好的材料,预硬易切削钢(一般28~35HRC之间)、耐蚀钢、硬质合金钢以及时效硬化型钢、冷挤压成型钢。
表面工程可以弥补模具材料的不足,降低模具材料的研发及加工的费用。
近年来迅速发展起来的激光表面强化技术、物理气相沉淀技术(PVD)、化学气相沉淀技术(CVD)、热喷涂技术等新的表面技术,而传统的表面技术(如热扩散、电镀)也有很大的完善与发展,如电镀技术已经发展到复合电镀技术。
2.5 基于信息注塑模具的制造新模式。
与注塑模具制造活动有关的信息包括产品的信息和制造信息。
现代制造过程可以看作是原材料或毛坯所含的信息量的增值过程,信息流驱动将成为制造业的主流。
它包括两个层面:一是通过企业内部的局域网,完成模具报价、人员的安排、制品原始数据、模具加工工艺、质量检测、试模具与交付等任务;二是通过企业外部的互联网完成企业与用户、与外协企业之间的信息交换,这种制造方式必须通过动态联盟(Virtual Organization)这种新的生产模式来实现的。
动态联盟分三层:紧密层、合作关系层和松散层。
3 新兴特殊注射成型技术对模具制造的发展要求注射成型技术作为塑料加工成型方法中最重要的方法之一,已经得到相当广泛的应用。
据统计,注塑制品约占整个塑料制品的20%~30%,而在工程塑料中有80%以上的制品是采用注塑成型加工的。
但随着塑料制品应用的日益广泛,不同的领域对塑料制品的开头精度、功能成本等方面提出了很多更高的要求,因此在传统注塑成型技术的基础上,又发展了许多特殊的新兴注塑成型技术,如低压注射成型、熔芯射击成型、装配注射成型、磁场定向注射成型、单色多模注射成型、气体辅助注射成型、薄壳注射成型技术等。
因些必须改变注塑模具的设计和制造体系,才能够满足成型要求。
另外,随着微机电系统的产业生命线的进展,微细型注塑模具设计与制造技术的研究近年来得到了人们的重视,随着MEMS产业化的进程,微注塑成型技术有着巨大的潜力和发展空间。
微型注塑成型通常用于医疗、电信、计算机、电气等领域,医疗和电子器械越来越小型化,因此对人们希望制件可以做得越来越小。
微型注塑成型有许多优点,如工模具的成本可以更低,而且原料的成本也大大的降低,研究适合微型注塑模具和微型注塑机的成型理论和制造方法,寻找和研制适合微型塑料制件生产的塑料原料,以及开发相应的检测仪器设备,已经成为目前国内外的研究热点。