1922_基于ProToolkit的止動片沖裁模三維參數(shù)化設計

1922_基于ProToolkit的止動片沖裁模三維參數(shù)化設計,基于,protoolkit,止動片沖裁模,三維,參數(shù),設計 Recent achievements in computer aided process planning and numerical modelling of sheet metal forming processesM. Tisza*Manufacturing and processingAbstractPurpose: of this paper: During the recent 10-15 years, Computer Aided Process Planning and Die Design evolved as one of the most important engineering tools in sheet metal forming, particularly in the automotive industry. This emerging role is strongly emphasized by the rapid development of Finite Element Modelling, as well. The purpose of this paper is to give a general overview about the recent achievements in this very important field of sheet metal forming and to introduce some special results in this development activity.Design/methodology/approach: Concerning the CAE activities in sheet metal forming, there are two main approaches: one of them may be regarded as knowledge based process planning, whilst the other as simulation based process planning. The author attempts to integrate these two separate developments in knowledge and simulation based approach by linking commercial CAD and FEM systems.Findings: Applying the above approach a more powerful and efficient process planning and die design solution can be achieved radically reducing the time and cost of product development cycle and improving product quality.Research limitations/implications: Due to the different modelling approaches in CAD and FEM systems, the biggest challenge is to enhance the robustness of data exchange capabilities between various systems to provide an even more streamlined information flow.Practical implications: The proposed integrated solutions have great practical importance to improve the global competitiveness of sheet metal forming in the very important segment of industry.Originality/value: The concept described in this paper may have specific value both for process planning and die design engineers.Keywords: Analysis and modelling; Knowledge and simulation based systems1. Introduction In the recent years, the role and importance of metal forming processes in manufacturing industry have been continuously increasing primarily due to its material- and cost-effective nature. It is further emphasised by the recent advances in tools, materials and design, which in turn provide significant improvements in the mechanical properties and tolerances of the products. It is also characteristic for metal forming processes that the final shape of the component cannot be produced generally by a single operation, but more often several operations should be performed to transform the initial simple geometry into a more complex product. Moreover, in the recent years metal forming develops in the direction of net-shape or near-net-shape manufacturing to reduce the need for subsequent machining operations and to minimise the total manufacturing represent very important and complex tasks. The global competition also requires that manufacturing industry – besides the skill and the experience accumulated in the shop practice – should increasingly utilise proven techniques of Computer Aided Engineering for rapid and cost effective process design and tool manufacturing. The application of various methods of Computer Aided Engineering has become one of the most important topics in manufacturing industries and particularly in the automotive industry. The application of various CAE techniques practically covers the full product development cycle from the conceptual product design through the process planning and die design up to the manufacturing phase of the production. CAE techniques are widely used in sheet metal forming, for example to predict the formability, to determine the type and sequences of manufacturing processes and their parameters, to design forming tools, etc. The importance of the application of CAE tools becoming more and more important as the manufactured parts are becoming ever increasingly complex. As the need for the widespread application of CAE techniques driven by the demand of global competitiveness accelerates, the need for a robust and streamlined Process and Die Design Engineering (PDDE) becomes more and more crucial. Recently, there are two main approaches to achieve these goals. One of them is the application of knowledge-based expert systems, which are generally based on simplified plasticity theory and empirical technological rules. There are a great number of papers dealing with the exclusive use of knowledge-based systems both in sheet and bulk metal forming [1-3]. However, the exclusively knowledge based solutions have certain disadvantages: they usually cannot provide an enough accurate solution to the problem since these systems are generally based on simple technological rules with limited validity. Therefore knowledge-based systems cannot predict for example the material flow, and usually cannot provide the accurate stress and strain distribution inside the component. As another approach, numerical techniques (recently mainly finite element modelling) are applied for the analysis of the plastic deformation [4-6]. The main objectives of the application of numerical process simulation in metal forming are to determine appropriate process parameters and to develop adequate die design by process simulation, to improve part quality by predicting process limits and preventing flow induced defects. Besides these, numerical process simulation also leads to reducing process and die try-out, as well as shorter lead times, while significantly reducing manufacturing costs. But the exclusive use of numerical modelling – like it is the case in the exclusive use of knowledge-based systems – has also some drawbacks, too. In spite of the enormous development of hardware and software facilities, the reliability of results is often dependent on the experiences of the user. It is partly due to the large number of operating parameters whose influence should be investigated, and partly due to the numerical difficulties caused by the complexity of the applied mathematical model to describe the material behaviour. Therefore, in the recent years the integration of these two fields (i.e. the knowledge-based systems and numerical modelling) has gained primary importance [7]. 2. Process planning and die-design in sheet metal One of the main drawbacks in industrial practice hindering the even more wide application of simulation techniques that the output results of simulation packages are not usually directly and easily usable for computer aided die design. Obviously, there are tremendous efforts to successfully link CAD and FEM systems, however, still there are a lot to do in this field [8]. This solution requires a fully integrated approach of computer aided product design, process planning and die design, as well as the finite element simulation of the forming processes. It means that simulation tools should be efficiently used throughout the whole product development cycle [9]. This concept will be illustrated through the examples of automotive part production. In our practice, we use Unigraphics NX 4 as a commercial CAD system for supporting the Computer Aided Process Planning and Die Design tasks and the AutoForm 4.05 and PAM-STAMP 2G are used as the numerical simulation tools, however, the principles applied here can be similarly adopted by using different CAD and simulation packages, too. Before analysing this integrated solution, let’s summarize the main features of forming process planning and die design in so-called conventional CAD environment .2.1Process planning and die-design in conventional CAD environmentStamping industry applies CAD techniques both in the process planning and die design already for many years. However, in a ?traditional” CAD environment, these are practically stand-alone solutions, i.e. for example a knowledge based process planning solution is applied for the determination of the necessary types of forming processes, even in some cases, the forming sequences can be determined in this way together with the appropriate process paramteres, too. After determining the process sequences and process parameters, the forming dies are designed using sophisticated CAD systems, however, still we do not have any evidence whether the designed tools will provide the components with the prescribed properties. Therefore, before it goes to the production line, usually a time- and cost consuming try-out phase follows, as it is shown in Fig.1 If the try-out is successful, i.e. the die produces parts with no stamping defects, it will be sent to the stamping plant for production. On the other hand, if splitting or wrinkling occur during the tryout, the die set needs to be reworked. It means that we have to return first to rework the die construction by changing the critical die parameters (e.g. die radii, drawing gap, etc.). If it does not solve the problem, a new die design, or a new process planning is required. Some cases, we have to go back even to the product design stage to modify the product parameters. The more we go back the higher the development and design costs are. Occasionally, the die set is scraped and a perfectly new product-, process- and die design is needed. As a result, die manufacturing time is increased as well as the cost of die making. 3. Process planning and die-design in sheet metalSimulation and Knowledge Based Systems – An Integrated ApproachAs it was mentioned before, this solution will be described through the example of an automotive sheet metal component using the Unigraphics NX (version 4.0) as the CAD system, and the AutoForm 4.05 as the FEM package, however, the principles applied here, can be adopted to other programs as well [10]. The selection of these two program packages can be explained by several reasons. On the one hand, both the Unigraphics and the AutoForm are among the most widely applied packages in the automotive industry in the World. On the other hand, these two systems are among the first to offer a special interface module to enhance the information and data exchange between CAD modelling and FEM simulations in both directions making possible the most efficient integration during the whole product development cycle. In the forthcoming sections, this solution will be described in detail following the road map of this simulation-guided process planning and die design procedure. 3.1.Geometric modelling of the sheet metal componentThe CAD model of the component created by the product design engineer is shown in Fig.3. As it often happens in the automotive industry, the component has a symmetric counterpart (so-called left and right handed or double attached parts). The part model is created in Unigrapics NX 4.0 CAD system as a solid model. However, FEM systems dedicated for sheet metal forming usually require surface models. Therefore, before exporting the part model a surface model should be created. This function is well-supported in most CAD systems. Depending on the simulation requirements, even we can decide which surface (top, middle or bottom) will be exported into the surface model. 3.2.Feasibility of the component formabilityIn most cases, process planning engineers would like to know right at the beginning whether the component can be manufactured with the planned formability operations. Therefore, after importing the surface model of the component with the AutoForm input generator, first a fast feasibility study should be performed. The AutoForm has an extremely well suited module for this purpose: in the so-called One-Step simulation module, this formability analysis can be done even if we do not have any or just very few information on the forming tools. Using this One-Step simulation procedure, a quick decision can be made if any modification of the part is required. Besides the part formability validation in this very early stage of product development, further important possibilities are also offered in this module including the analysis of slight part modifications, studying alternative material types and grade, or various thicknesses, material cost estimation and optimization, etc. If this feasibility study is successful as shown for example for this component in Fig.4, the work of process planning engineer can be efficiently supported by determining the optimum blank shape and sizes. 4. ConclusionsComputer aided engineering has a vital and central role in the recent developments in sheet metal forming concerning the whole product development cycle. The application of various methods and techniques of CAE activities resulted in significant developments: the formerly trial-and-error based workshop practice has been continuously transformed into a science-based and technology driven engineering solution. In this paper, an integrated approach for the application of knowledge based systems and finite element simulation is introduced. Applying this knowledge and simulation based concept for the whole product development cycle – from the conceptual design through the process planning and die design as an integrated CAE tool – provides significant advantages both in the design and in the manufacturing phase. Sheet metal forming simulation results today are already reliable and accurate enough that even tryout tools and the time consuming tryout processes may be eliminated or at least significantly reduced. Thus, the integrated solution described in this paper results in significantly shorter lead times, better product quality and as a consequence more cost-effective design and production.AcknowledgementsThis research work was jointly financed by the Hungarian Academy of Sciences (MTA) and the National Science Foundation (Ref. No.: OTKA NI 61724). This financial support is gratefully acknowledged. References[1] S.K. Sitaraman, T. Altan, A Knowledge Based System for Process Sequence Design in Sheet Metal Forming, Journal of Materials Processing and Technology (1991) 247-271. [2] N. Alberti, L. Cannizaro, F. Micari, Knowledge Based Systems and FE Simulations in Metal Forming Processes, Annals of CIRP 40 (1991) 295-298. [3] L. Eshelby, M. Barash, W. Johnson, A Rule Based Modelling for Planning Axisymmetric Deep-drawing, Journal of Mechanics Sciences (1988) 1-113. [4] A. Makinouchi, Sheet Metal Forming Simulation, Journal of Materials Processing and Technology 60 (1996) 19-26. [5] A.E. Tekkaya, State of the art of Simulation in Sheet Metal Forming, Journal of Materials Processing and Technology 103 (2000) 14-22. [6] T. Altan et al., Simulation of Metal Forming Processes, Proceedings of the 6th International Conference ICTP, Nuremberg, 1999, 23. [7] M. Tisza, Numerical Modelling and Knowledge Based Systems in Metal Forming, Advanced Technology of Plasticity 1 (1999) 145-154. [8] A. Andersson, Information Exchange within Tool Design and Sheet Metal Forming, Journal of Engineering Design 12 (2001) 283-291. [9] A. Andersson, Comparison of Sheet Metal Forming Simulation and Try-out Tools in Design of Forming Tools, Journal of Engineering Design15 (2004) 551-561. [10] M. Tisza, Numerical Modelling and Simulation: Academic and Industrial Perspectives, Materials Science Forum 473-474 (2005) 407-414. 近年來計算機輔助工藝規(guī)劃和板料成形數(shù)值模擬過程米蒂薩河*制造和加工摘要目的：本文：在最近的10 - 15年，計算機輔助工藝設計及模具設計的進化成為其中一個最重要的工程工具板料成形過程中，特別是在汽車工業(yè)。這一新興的角色是強烈的迅速發(fā)展，強調了有限元模型。本文的目的是給出一個概述，關于近年來所取得的成就在非常重要的板料成形領域，介紹一些在這個發(fā)展活動中的特殊結果。設計/方法/途徑:對板料成形 CAE 活動，主要有兩種方法：其中一個可能被看作是基于知識的工藝設計，而另一個基礎工藝規(guī)劃為仿真。作者試圖通過商業(yè)CAD 系統(tǒng)和有限元方法整合這兩個獨立發(fā)展的基礎知識和仿真方法。結果：應用上述方法一個更強大、更高效的工藝設計及模具設計的解決方案可能達到徹底降低芯片制造時間和費用，降低產品開發(fā)周期，提高產品質量的效果。研究局限性/含義：由于有限元方法和 CAD 系統(tǒng)不同的造型方法 ,最大的挑戰(zhàn)是提高數(shù)據(jù)交換能力較強的魯棒性之間的不同系統(tǒng)以提供一個更精簡的信息流動。實際應用：該綜合解決方案對于提高板料成形過程中很重要的工業(yè)環(huán)節(jié)的全球競爭力有重要的現(xiàn)實意義。創(chuàng)意/價值：本文中介紹的概念對于工藝設計及模具設計工程師都可能有特定價值。關鍵詞：分析和模型；基于知識和仿真系統(tǒng)。1.介紹近年來成型過程的作用與重要性在制造業(yè)中不斷增加，主要由于其材料和精打細算的性質。這是進一步強調了近年來的工具、材料和設計，從而提供顯著的改善力學性能及公差的產品。它也是對金屬板料成形特點中最后形成的組件不能由一般生產的一次手術，但是更常見的幾種手術應把初始簡單的幾何變換成一個更復雜的產品。此外，近年來在金屬成形的方向發(fā)展分析鈑制帶輪近凈減少或制備生產需要后續(xù)加工操作，并盡量避免妨礙總生產成本。因此，金屬成形工藝設計和工具設計代表了一個非常重要且復雜的任務。全球競爭也需要制造業(yè)，除了在商店實踐的技能和經驗積累，也應該越來越利用電腦輔助工程實踐技術的快速和低成本的工藝設計和工具制造。應用多種多樣的計算機輔助工程已成為最重要的課題之一，特別是在制造業(yè)的汽車工業(yè)。各行各業(yè)的 CAE 技術應用幾乎涵蓋了從產品概念設計到工藝設計及模具設計到制造階段的生產的全部產品開發(fā)周期。CAE 技術廣泛應用于板料成形，預測，確定型號序列參數(shù)和生產流程，設計成形模具，等。應用 CAE 技術對于制造日益復雜的工具零件的重要性越來越大。因為需要 CAE 技術的廣泛應用來加速推動全球競爭力，需要一個良好的魯棒性和流線型的過程和模具設計工程(PDDE)變得越來越重要。最近，有兩個主要的方法來實現(xiàn)這些目標。其中一個是基于知識的專家系統(tǒng)的應用，這通常是基于簡化塑性理論和實證技術規(guī)則。將會有非常大量的文件處理知識系統(tǒng)專用權都和大量的金屬成形板材[1 - 3]。然而，專門為以知識為基礎的解決方案有一定的缺點：他們通常無法提供足夠精確的解決這個問題的方法，因為這些系統(tǒng)通常基于簡單的技術規(guī)則和限制的有效性。因此知識系統(tǒng)無法預測例如物流，而且通常不能提供準確的應力和應變分布在組件。作為另一個方法，數(shù)值方法(主要是有限元模型)被廣泛應用于分析塑性變形[4 - 6]。應用的主要目的數(shù)值模擬在金屬成形過程中，確定合適的工藝參數(shù)和提供足夠的模具設計過程仿真，提高產品的質量，防止被預測的工藝范圍流激缺陷。除了這些，也會通過數(shù)值過程模擬減少工藝、模具選拔以及交貨周期，同時大大降低制造成本。但獨家使用數(shù)值模擬的研究 ——就象它是這個案子獨家使用知識系統(tǒng)，也有一些弊端，也具有一定的參考價值。盡管硬件和軟件設施快速發(fā)展，其可靠性結果也往往取決于用戶的經驗。其中一部分是由于大量的操作參數(shù)的影響需進行調查,另一部分是由于應用數(shù)學模型描述材料的行為造成數(shù)值困難的復雜性。因此,在近年來的整合這兩個領域（如知識系統(tǒng)和數(shù)值模擬）的研究已獲得了重要進展[7]。2.工藝設計和 die-design 金屬片一個主要的缺點在工業(yè)實踐阻礙更廣泛應用仿真技術，輸出結果的模擬軟件包通常不直接和容易使用計算機輔助模具設計。顯然，還要有巨大的努力去成功連接計算機輔助設計和有限元系統(tǒng)，但是，在這一領域仍然有很多事情需要做[ 8]。這就需要一個完全集成的方法計算機輔助產品設計，工藝設計和模具設計，以及有限元模擬形成過程。這意味著仿真工具應該被有效的利用整個產品開發(fā)周期[9]。這一概念將通過實例的汽車零件生產。在實踐中，我們使用 Unigraphics NX 的4作為商業(yè) CAD 系統(tǒng)支持計算機輔助工藝設計及模具設計的任務、AutoForm 4.05和 PAM-STAMP 2 G 作為數(shù)值模擬工具，然而，采用的原則在這里同樣可以通過使用不同的計算機輔助設計與仿真軟件包。在分析這種綜合的解決方案,讓我們總結形成過程規(guī)劃的主要特點及模具設計在所謂的傳統(tǒng) CAD 環(huán)境。2.1.傳統(tǒng) CAD 環(huán)境中的工藝設計及模具設計沖壓行業(yè)應用計算機輔助設計技術在工藝設計和模具設計已經很多年了。然而，在傳統(tǒng)的環(huán)境，這些幾乎是獨立的解決方案，即例如基于知識的工藝規(guī)劃的解決方案是用于確定必要的類型的形成過程中，甚至在某些情況下，形成序列也可以用這種方法連同適當?shù)倪^程 paramteres。在確定過程中的序列和工藝參數(shù)，成形模具的設計采用了先進的計算機輔助設計系統(tǒng)，然而，我們仍然沒有任何證據(jù)是否設計的工具將提供部分規(guī)定的特性。因此，在它的生產線，通常是一個時間和成本消耗，試行階段如下，顯示圖1。如果試驗是成功的，即模具生產零件沒有沖壓缺陷，它將被發(fā)送到沖壓廠生產。另一方面，如果分裂或起皺發(fā)生在試模，模具需要重做。這意味著我們必須返回第一返工的模具結構改變的關鍵參數(shù)（如模具模具半徑，模具間隙，等。 ） 。如果不解決這個問題，一個新的模具設計，或一個新的工藝規(guī)劃是必要的。某些情況下，我們必須返回到產品設計階段的產品參數(shù)修改。我們越回較高的開發(fā)設計成本。偶爾，模具刮和一個完美的新產品，工藝和模具的設計是必要的。因此，模具制造時間增加以及成本的模具制作。3.仿真和基于知識的系統(tǒng)–綜合方法就像前面提到的，該方案將通過一個例子：汽車鈑金部件使用 UG（4版）為計算機輔助設計系統(tǒng)，AutoForm 4.05為有限元分析軟件包,然而,這個原則應用在這里,也可以用于其他方案[10]。這兩個項目的選擇軟件包可以解釋為幾個原因。一方面，這兩個 UG 和AutoForm 是最廣泛應用的軟件包在世界汽車工業(yè)。另一方面，這兩個系統(tǒng)是最早提出一項特殊的接口模塊，提高信息和數(shù)據(jù)交換之間的建模和數(shù)值模擬兩個方向可能是最有效的整合在整個產品開發(fā)周期。在即將到來的部分，這個方案將被用來詳細描述 simulation-guided 地圖的工藝設計及模具設計過程。3.1.金屬板材的幾何造型的組成部分先進的 CAD 模型的組成由產品設計工程師被顯示在圖。因為它常發(fā)生在汽車行業(yè)、組件都有一個對稱的對手(所謂的左、右撇子或雙附件)。部分模型 Unigrapics NX 創(chuàng)造4.0 CAD 系統(tǒng)作為一個實體模型。然而，專用有限元板料成形系統(tǒng)通常需要表面模型。因此，在出口前部分模型表面模型應該被創(chuàng)造出來。這個函數(shù)是良好的支持在大多數(shù) CAD 系統(tǒng)。根據(jù)仿真需求，即使我們可以決定哪些表面(上層、中層或底部)將被出口到曲面模型。3.2.部分成型的可行性在大多數(shù)情況下，工藝設計工程師想知道部件可以開始生產的成形性與計劃行動是否正確。因此，在引進曲面模型的輸入組件 AutoForm 發(fā)電機，首先應進行快速的可行性研究。這 AutoForm 有極適合模塊為這個目的：在所謂的一步法仿真模塊，該成形性能做了分析，即使我們沒有任何信息或者只是很少的形成的工具。使用這個一步仿真程序，一個快速的決定，可以做任何修改的部分是必需的。除了部分成形性能驗證在這個早期階段的產品開發(fā)，更重要的可能性也提供在本模塊包括分析細微部分修改，研究替代材料的類型和等級，或不同的厚度，材料成本的估算和優(yōu)化，等。如果這個可行性研究是成功的，如圖所示，例如該組件圖工藝規(guī)劃工程師的工作，可以有效地支持確定最佳毛坯形狀和尺寸。4.結論在金屬板料成形的整個產品開發(fā)周期中計算機輔助工程具有重要的核心作用并且扮演著重要的角色。應用 CAE 各種方法和技術的活動產生重大進展：以原試車間實踐為基礎一直不斷轉化為科學和技術驅動的工程解決方案。本文提出了一個綜合的方法的應用，以知識為基礎的系統(tǒng)和有限元模擬方法。應用這些知識和仿真的基礎概念，為整個產品開發(fā)的周期，從概念設計到工藝設計及模具設計為一體的 CAE 工具，具有明顯的優(yōu)勢，無論在設計和制造階段。今天的金屬板料成形模擬結果已經足夠精確可靠，甚至調試工具和耗時的調試過程可能被取消或至少顯著降低。因此，本文描述的綜合解決結果顯著地縮短交貨期，提高了產品質量，因而更具成本效益的設計與生產。鳴謝這項研究工作是由匈牙利科學研究院（中國）和美家科學基金會（參考編號：otka 鎳61724）共同出資。對這種財政支持表示感謝。參考文獻[1] S.K. Sitaraman, T. Altan，一個基于知識的系統(tǒng)的工藝流程設計在板材成型過程中，材料加工技術雜志（1991）247-271。[2] N. Alberti, L. Cannizaro, F. Micari，基于知識的系統(tǒng)和有限元模擬金屬成形過程中，志40（1991）295-298。[3] L. Eshelby, M. Barash, W. Johnson，一個以規(guī)則為基礎的模擬規(guī)劃軸對稱拉深，力學學報科學（1988）1-113。[4] A. Makinouchi，板料成形模擬，材料加工技術雜志，60（1996）19 - 26。[5] A.E. Tekkaya，國家藝術的仿真技術在板料成形，材料加工技術雜志，103（2000）14 - 22。[6] T. Altan et al.，模擬金屬成型過程，第六屆國際會議國際理論物理中心，紐倫堡，1999，23。[7] M. Tisza，數(shù)值模擬，基于知識的系統(tǒng)在金屬成形，工藝先進的可塑性，1（1999）145-154。[8] A. Andersson，信息交換的工具設計和鈑金成形，工程設計學報12（2001）283-291。[9] A. Andersson，比較鈑金成形模擬及試驗工具成型刀具的設計，工程雜志（2004）551-561design15 。[10] M. Tisza，數(shù)值模擬與仿真：學術和工業(yè)的角度來看，材料科學論壇 473-474（2005）407-414。