CHIPLESS TECHNOLOGIES AND CRITERIA OF CA SYSTEMS CHOICE FOR TECHNICAL PRODUCT PREPARATION IN THIS AREA

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1 CHIPLESS TECHNOLOGIES AND CRITERIA OF CA SYSTEMS CHOICE FOR TECHNICAL PRODUCT PREPARATION IN THIS AREA Jozef KUBA, Ivan KURIC University of Žilina, Faculty of Mechanical Engineering Department of Measurement and Automation, 01026, Slovak Republic Introduction The elimination of routine work and negative influence of human factor in technological documentation creation is contingent on computer support in frame of technical product preparation (TPP). The view of TTP computer support in area mechanical engineering would be probably wide, therefore the article is focused on analyse and exercise CA systems for forming and casting area. The computer support aim would be the largest scope and activities intersection between TPP area and CA systems possibilities (Fig.1). Their absolute covering would be ideal case. But it would be mean absolute computer support, which is difficult reachable in frame of these technologies. Fig.1 Intersection of solved activities in TPP and CA systems 2. What are criteria for choosing CAD system? If domain CAD systems fall in designing department area, it merits attention from aspect of technological product preparation (TgPP), because their output dates become input dates for TgPP. Review of CAD system choice for forging and casting is very important question.

2 The actuality is appreciation following facts: measure of 3D modelling necessity necessity of special module for tool design necessity of documentation management At assortment, which composes of symmetrical parts or there are not needy digital information pertinent to part capacity (for determination shape complexity, deformation energy, etc.), there will be sufficient CA system with 2D output. The creators of CAD applications increasingly offer modules for special tools. For example it is possible to adduce CATIA module for design of casting moulds or Pro/ENGINEER modules for press tools construction and casting moulds design. It is needy thoroughly to analyse production character, which decides about necessity these modules. About using of the shell for documentation management decides mainly its extent, which is dependent on quantity of production and assortment. Documentation management (AutoCAD Design Center e.g.) allows not only whole drawing copying but also blocks or levels copy. Further it is advisable to explicate important question, which concerns paper documentation (Fig. 2). Fig. 2 Paper documentation processing And the question consists in that whether to digitise paper documentation or no. Positive standpoint means to buy scanner. Is there raster format sufficient or is vectoring needy? If vectoring is needy then it is necessary to gain software tools serving to vectoring of documentation (VP..NT e.g.), which not always fulfil their intention. Mainly in the case if paper documentation is in damaged stage from graphic standpoint aspect. In this context is sometimes more effective to create documentation from beginning (new modelling). All of refereed modules and shells are evidently pertinent to exercise the resources for their acquisition.

3 3. What are criteria for choosing CAE system? The choice of suitable CAE system for forging and casting area is contingent on part shape symmetry. Subsystems resolving of operations simulation for the production of shape symmetrical parts are offered in lower cost levels. But on the other side in designing of production technology such parts are often adequate the conventional methods of tasks solving (nomographs, etc.). The cost ranges of 3D simulation systems are still enough high and they essentially influence on rate their expansion (Marc/Autoforge, MSC.SuperForm, Forge 3D, Magmasoft, Simtec...) The computing time of full making product simulation of shape complexity part (Fig.3 e.g.) is also enough high. Fig. 3 Part meshing If in this period efficiency and quality of simulation systems for forging and casting escalate, the claim on input dates (boundary conditions) is always very high. It means that education level and computer support for the input technological parameters determination have to have adequate quality. In computer simulation possibilities are not every time to substitute practical test (experiment) of technological process realised in concrete manufacturing conditions. Full congruence of computer simulation of real process could be possible only if source algorithms and date databases of simulation application cover all variations of pertinent rules and linkage relations of real process. The questionable fact is choice of CA systems in case of multitechnologies using (Fig.4.). Fig. 4 Simulation of compound technologies

4 There is necessary to consider putting on more CA systems for solving different problems. How example of modules it is possible instance MAGMAfill, which simulates mould filling with liquid metal and MARC/Autoforge which simulates pressing process. The offer of CA systems for TgPP in forging and casting area is rather close in our market (e.g. OPTI). The majority part of commercial systems for computer support of TgPP is created mainly for chip technologies. The smaller production subjects contrive with simple, common widespread database systems (e.g. FoxPro) or office packets (e.g. MS Office), where is possibly through the medium of language Visual Basic to create suitable software tools for practical using. The complete computer support realisation in TPV frame is claused by the problem-free transmission of dates among CA systems (Fig.5). But such as the transfer non-geometric dates between CAD and CAPP systems can be problem. Despite of constantly increasing of cross support for input (output) formats in CA systems and proclaimed problem-free transfer of dates (e.g. Step), it is necessary to pay attention to this fact, especially in cases of upgrading of existent hardware and software base for TPP. Fig. 5 Example dates transfer Despite of previously mentioned facts, computer support of TPP is key path towards quality increasing of complete process realisation from preliminary order receiving to part product realisation. Whole process of part realisation in the adequate measure of quality can ensure only special software. The compensation by common application (e.g. MS Excel, MS Access) can solve this problem only in part TPP division. The complete elimination of technologist activity is not possible and nor yet desirable in concern to result quality. The other aspect it is that not all the parameters can be determined without intuition and experiences. Forging and casting are characterised by wide spectrum of empirical relatives, correction coefficients or experiences using and so employment of CA systems and self-software resolutions are problematical somewhen.

5 The complexity of this technology area is contingent on variety subtechnologies, where is necessary reinterpreting a lot of different process parameters (hydrostatic height, centrifugal force, deformation force, forge energy, etc.) 4. Conclusion In spite of mentioned problems the computer support importance in this very complicated area of mechanical engineering technologies is unimpeachable. The computer support relevancy in forging and casting area consists in the time and expenses reduction, potential failures prediction, flexibility of technological process design and production quality improvement. References [1] Kuric, I. Computer Aided Process Planning. Politechnika Lódzka, Bielsko-Biala, 1999, ISBN [2] Sládek, A., Meško, J., Doni, T. : Beztrieskové technológie, Edis, Žilina, 2000 [3] Stroka, R.: Integration of CAPP and CAD/CAM systems. SOP 2000, Cracow, October 2000, ISBN X [4] Janušová, R.: Utilisation of product models based on a simultaneous engineering. SOP 2000, Cracow, October 2000, ISBN X Conference Bielsko-Biala, 2003