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Domestic and foreign car coverage Die Design Overview1 Introduction In recent years, Chinas car market has developed very rapidly in 2002 in car sales more than one million on the basis of in 2003 to 2 million people relations forward, reaching 1.97 million. However, in the car heat rapidly warming, had to face the embarrassment of this reality-market best-selling vehicle for the majority of people must be directly imported from abroad. As domestic car cover mold design and manufacturing capability on the whole is relatively weak, in order to produce these models, each company had to spend hundreds of millions or hundreds of billion of overseas procurement die. People with foreign automobile companies, because the relatively small scale of production, This has resulted in motorcycle smoothing wood into the mold much higher than foreign cars, This is also produced cars along with high wood manufacturing into one of the main reasons. 2 Domestic car coverage Die development capability Major car manufacturers to Die : Die Manufacturing Co. Ltd. of FAW, Dongfeng Motor Die Works, Tianjin Automobile Die Company, CAC Integration Technology Co., Ltd Nanjing mold equipment, Shanghai Auto Body 1000 margin Die Company. Most people as a domestic car production and sales of commercial-vehicle population of Shanghai Limited, also has its own mold design and manufacturing departments (TMM Division). Currently, Although domestic Die in Car cover the mold design and manufacturing has a small capacity, auto plants can undertake some development projects die, but for a very high surface accuracy and surface quality requirements of the outside panel. It is especially the high-grade cars outside panel, auto plants rarely die by the will of such domestic development.Shanghai Public Motors Limited in order to reduce vehicle production costs, but also to increase the companys core technical competencies, Since the beginning of 2001, set foot in the car stamping die design and manufacturing fields. 2001 -2002 completed POLO cars manually presses the production line 10 Die simple parts , the companys quality assurance department as well and put into production. Beginning in 2002, the type of people to the complex, automation, 6000kN the design and manufacture of automatic production line POLO cars tyres. Die Block (dimensions of the parts, deep drawing deep, complex shape) in 2003, in order to further enhance the design and manufacture of mold ability and level We get involved in the Multi-Position 20000kN Press and 10000kN automatic production line of die design. Shanghai over the past number of people in many public spaces 20000kN Press on the use of the mold, all u need to progress, Die domestic business still lacks the ability to design and manufacture the mold. To this end, we chose POLO Car column plate mold design. 20000kN Multi-Position Press is the worlds most advanced presses, integration, a very high degree of automation. Of course, this right mold design requirements also increased accordingly. Parts Feeding height, distance, location manipulator strict requirements ensure that the manipulator in the course of the campaign and die without interference, so the mold design for space on a small lot. In considering many factors, we finally completed the whole mold design, CAD state assembly as shown in figure 1. In addition, we have completed the POLO cars 10000kN automatic production line of the rear wheel cover mold design, In last years build on that. These successful completion of the Shanghai marks the number of people die design capability has reached advanced domestic level. thus for the future of Shanghai people die Domestic car lay a solid foundation. Nevertheless, with the international advanced level, the more people there are still gaps, For example, in the car outside cover mold design or from the air. Die in Car, the most difficult of the outer covering die design, mainly in the following two aspects :(1)Overcome by the resilience of parts surface deviations Breakdown, wrinkling, Rebound car is stamping process of forming the main shortcomings, as car outside panel dimensions. deep drawing shallow, plastic deformation low level generally will not crack, Resilience as a result of such parts on the manufacturing process and the main problems, it will seriously affect the parts with the mutual relations. Finite element simulation software in the stamping die design universal application, has been able to accurately predict rupture and wrinkle-free. thus contribute to the design of appropriate auxiliary surfaces to improve the process of drawing materials flow, improve parts forming ft. However, to date) unknown. Most of the finite element software can not be accurately forecast Stamping Die them removed from the rebound after deformation. Therefore, the external panel dealing with the resilience of the major changes to rely on the experience of the die face, stamping parts are forming over, to offset rebound led to the deformation. (2)Stamping the pick-up As foreign coverage (eg front cover plate, the roof and fender panels) are subject to complex flanging plastic or anticipated beading crafts, This makes the design of the mold structure, we must consider the ram after forming the pick-up, the current people are relying on more complex Wedge institutional linkages to achieve some of the work to mold parts his resignation to achieve to enable them to pieces. The resulting mold of the entire structure is very complicated.3 Foreign coverage Die Design Currently, foreigners Motors Corporation in order to reduce mold development and manufacturing costs, shorten production cycles, In addition to cars outside panel of people out of the car Stamping Die Mold were left to professional companies (such as Fontana Pietro. Kuka.Laepple.Schuler Cartec.Ogi-ha la-Fuji Techniaca etc.) to design and manufacture, these companies have strong development capabilities, and in some parts of the manufacturing mold with unique advantages. But as auto plants, taking into account the development of new models in the process of confidentiality, such as the right-wing boards, suitcase covers, doors, side-Wai, the roof front cover and other sensitive parts of the die, die by their own manufacturing sector to design and manufacture. 3.1 Software Environment Stamping die design, in addition to the need for CAD software, also large-scale application of the finite element simulation software If AutoForm.PamStamp. DynaForm. Indeed, aided design stamping process. Below, AutoForm as an example to show how the use of CAE software design process of drawing surfaces.AutoForm is supplied by the Swiss Development professional rapid simulation of sheet metal forming software can be used in sheet, welded plate stamping, such as Hydroforming process simulation, with different functional modules, can also be used for single-step stamping parts and the simulation of forming processes of drawing surfaces (Addendum) Design . Car stampings, About two-thirds of the use of AutoForm Diedesigner Module Module Design A ddendum the module under specified by the designer or by the software automatically generate pressure-ring face and and the process of multi-added section of the line (Profile), to produce rapid-added process, Drawing for the simulation process, as shown in Figure 2. V-ring face and Profile parameter can be the adjustment. This rapid design is based on surface Addendum Construction of the rough, curved surface film itself, and between the curved surface of the film is not very continuous fairing, Despite this surface is not used directly to the mold surface machining. But the simulation accuracy is not affected people. According to the simulation results. designers can easily add-on technology adjustment until simulation results meet design requirements. Finally, will Blankholder circle Profile Addendum to surface and neutral data format output IGS or VDA, CAD software for surface reconstruction and digital-analog integrated products, will be able to be machined can use the drawing process a few Die Mold.Stamping Process traditional design methods : First, on the basis of experience, the use of CAD technology to add noodles. Secondly, CAD will be transmitted to the model number of AutoForm software such as CAE deep drawing process simulation; According to the simulation results. in CAD add-on process adjustments and a few new CAD - CAE pass to start new simulation, Until meet the requirements for competition. This is one from CAD to CAE to return to the CAD kept in the process. Because each of the CAD surface structure than in AutoForm are complex, therefore, The whole process will have to spend much more time. And the new method of stamping process in the design stage, Diedesigner Module used in AutoForm software design and adjust the deep drawing process surfaces with the traditional design methods, we will be able to greatly improve the efficiency of design.A AutoForm is due to the rapid simulation software in a relatively short time stamping parts of the complicated process of forming the evaluation of membrane modules used to model discrete geometry, bound to reduce the simulation accuracy, therefore, Some car companies prior to the start of mold design will use high-precision simulation of the CAE software, Germany on the number of people using the software Indeed, Drawing on procedures for the simulation again (Indeed calculation software is based on the thickness of the shell element. to be more accurate results, However, the calculation of time spent AutoForm is usually several times that of the 10, The software is applicable to the ultimate test), Drawing all must pass Indeed Process simulation and validation to be feasible, in order for mold design.Mold design complete, the combination of drawings through the bubble acceptance model (Figure 3) different procedures with different colors of the lines marking the bubble model, the so intuitive and clear. Technology should also be organized, including designers, project planning, mold testing, Die operators and other stakeholders to discuss acceptance. For the stamping process difficult to solve the problem of forming, product development should also be invited to discuss personnel, look for changes in product design possibilities.3.2 Rebound amendment response The former is known, the rebound was cars outside panel forming process of the main questions are covered plate before example, conduct detailed analysis. Usually panel of the rebound following two categories :Large flat surface caused by the elastic response of buckling or collapse, as illustrated in figure 4, Part C Click below, dotted said parts removed from the mold and rebound occurred after the position. In such cases, the design process is not normally be considered. Technology products in a few die-face with some of the data from the product development departments of consistent data, and for die manufacturing. To tryout, and the specimens were seized compared with measurements, according to the deviation of drawing surface model amendment. If designers to control such problems have very rich experience, can be estimated in advance surface elastic recovery and the direction of offset, and will reverse its superposition of several product-development, Rebound consider seeking deformation of the surface of deep drawing process, the calculation process requires specialized computer software to accomplish, In Germany public, using the ICEM. Flanging plastic part by bending the rebound fold angle changes, as illustrated in figure 4 B Click below. For this kind of problem, in addition to the Department of Drawing and cutting edge, but also including flanging and Wedge plastic, plastic take-off process is forming 2 -3, to offset the springback. The process design work completed and reflected in the number of program modules.3.3 Wedge new outer body mold coverage on the application Currently, many of the new models outside panel, fender panels (Figure 5) front cover plate, the roof flanging plastic processes, used as a “revolving Wedge,“ new technology. The working principle see figure 6, rotating Wedge part of the cavity is required plastic stamping parts of the region, when the plastic process is complete, Cylinder - driven carriers to promote Wedge around rotating drum rotation, so as to achieve the purpose of the yield components, After the convenience of plastic parts, removed from the mold. Rotating Wedges advantages are : plastic parts for stamping parts and materials entrusted part of the mosaic is very fairing, Therefore, there is no obvious parts indentation; Die simple structure; maintenance is simple and low cost.4 Concluding remarks In recent years, through the tireless efforts and the car stamping die design and manufacturing capabilities made significant progress. However, the car is especially luxury cars outside the coverage of mold development, the international level and there are still more people gap. However, this gap is not narrowing, So long as we strengthen internationalexchanges and learn from their foreign counterparts in designing and manufacturing experience, car will be able to accelerate the coverage Die domestic process.
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