스템핑 공정 최적화 시스템의 개발 : 최적블랭크 설계와 최적배치의 일체화 Integration of Optimal Blank Design and Optimal Nesting

박종규,심현보 嶺南大學校 工業技術硏究所 2003 工業技術硏究所論文集 Vol.31 No.1

In recent years, design of an optimal blank shape is very important for sheet metal forming process in the automobile industry because the raw material cost rate is significant part in the automobile industry. With the design of an optimal blank shape, the engineer can protect a blank from an excessive holding force to improve the quality and reduce the ratio of material scrap. Therefore design of an optimal blank shape is inevitable in sheet metal forming process. However, if it causes a complicated shape of blank, it may be difficult to do the blank layout optimally. In this study, we developed software of optimal blank layout connected with the software of optimal blank shape design which was created in the past by the present authors. And by using these softwares, we would like to present the method in order to get optimal utilization ratio easily and precisely within short time for the sequence of works from design to blank layout.

가상 트라이 아웃 방법을 이용한 최적 블랭크 설계

정동원(Dong-Won Jung),고대림(Dae-Lim Ko) 한국기계가공학회 2008 한국기계가공학회 춘추계학술대회 논문집 Vol.2008 No.-

This paper made the process design for forming Bracket Front Back Frame Lower, determined the blank shape and size using PAM-STAMP, commercial software and evaluated formability. It has been proved that the optimal blank through the result forming analysis has advantage in terms of formability and spring back compared to the rectangular blank.

가상 트라이 아웃 방법을 이용한 최적 블랭크 설계

고대림(Dae-Lim Ko),정동원(Dong-Won Jung) 한국기계가공학회 2008 한국기계가공학회지 Vol.7 No.4

Sheet metal forming has some merits that are less loss of materials in process, less time-consuming and it makes mass product possible. The product produced by sheet metal forming process has high strength compared to the weight and better surface characteristics. Therefore, sheet metal forming process is a lot used in automobiles, aircrafts, electronics and appliances. This paper made the process design for forming Bracket Front Back Frame Lower, determined the blank shape and size using PAM-STAMP, commercial software and evaluated formability. It has been proved that the optimal blank through the result forming analysis has advantage in terms of formability and spring back compared to the rectangular blank.

유한요소법을 이용한 자동차 펜더 드로잉금형의 블랭크홀더에 관한 연구

이춘규 한국기계기술학회 2015 한국기계기술학회지 Vol.17 No.5

This study is strong enough in order to applied to the die structure of cars, the shape optimization with acceptable durability was carried out in the die using Altair Optistruct program. The volume shape through the optimization function is removed. It was to optimize stress according to the blank holder shape and Optimized the shape of the deformation. The optimization for Die holder with a robust structure and a simple functional Optimized die holder could mass the weight of 116 kg and the overall gain mass of 3% optimized.

Multicriteria shape design of a sheet contour in stamping

Oujebbour, Fatima-Zahra,Habbal, Abderrahmane,Ellaia, Rachid,Zhao, Ziheng Society for Computational Design and Engineering 2014 Journal of computational design and engineering Vol.1 No.3

One of the hottest challenges in automotive industry is related to weight reduction in sheet metal forming processes, in order to produce a high quality metal part with minimal material cost. Stamping is the most widely used sheet metal forming process; but its implementation comes with several fabrication flaws such as springback and failure. A global and simple approach to circumvent these unwanted process drawbacks consists in optimizing the initial blank shape with innovative methods. The aim of this paper is to introduce an efficient methodology to deal with complex, computationally expensive multicriteria optimization problems. Our approach is based on the combination of methods to capture the Pareto Front, approximate criteria (to save computational costs) and global optimizers. To illustrate the efficiency, we consider the stamping of an industrial workpiece as test-case. Our approach is applied to the springback and failure criteria. To optimize these two criteria, a global optimization algorithm was chosen. It is the Simulated Annealing algorithm hybridized with the Simultaneous Perturbation Stochastic Approximation in order to gain in time and in precision. The multicriteria problems amounts to the capture of the Pareto Front associated to the two criteria. Normal Boundary Intersection and Normalized Normal Constraint Method are considered for generating a set of Pareto-optimal solutions with the characteristic of uniform distribution of front points. The computational results are compared to those obtained with the well-known Non-dominated Sorting Genetic Algorithm II. The results show that our proposed approach is efficient to deal with the multicriteria shape optimization of highly non-linear mechanical systems.

Optimization of Initial Blank Shape for Minimizing the Trimming Process in Hot Stamping of T-Shaped Parts

Kim, Heung-Kyu,Shim, Hyun-Bo,Cha, Baeg-Soon,Song, Ga-Hyeong,Kim, Hyung-Jong Korean Society for Precision Engineering 2018 International Journal of Precision Engineering and Vol.19 No.5

Blank optimization in stamping is a way to reduce the cost of unnecessary material consumption or subsequent trimming operations by acquiring the final target part in a single forming process. There have been many studies on blank optimization in room temperature stamping, but few studies have yet been conducted in hot stamping. In this study, a blank shape optimization was conducted for a T-shaped part simulating a body center pillar. A finite element analysis (FEA) for the hot stamping process was performed using an appropriately assumed initial blank shape, and the blank shape was updated based on the shape error between the outline of the deformed blank obtained from the FEA and that of the target part. The shape error was calculated by applying the modified radius vector method. Hot stamping test was carried out using the optimal shaped blank predicted by the FEA. It was confirmed that the outline of the deformed blank obtained by the actual test was very close to the outline of the target part. From the results of this study, it can be seen that the blank optimum design technique at room temperature stamping can be applied to the case in hot stamping.

Development of An Optimal Layout Design System in Multihole Blanking Process

Lee, Sun-Bong,Kim, Dong-Hwan,Kim, Byung-Min Korean Society for Precision Engineering 2004 International Journal of Precision Engineering and Vol.5 No.1

The blanking of thin sheet metal using progressive dies is an important process on production of precision electronic machine parts such as IC leadframe. This paper summarizes the results of simulating the progressive blanking process by means of LS/DYNA. In order to verify the influence of blanking order on the final lead profile and deformed configuration, simulation technique has been proposed and analyzed using a commercial FEM code, LS/DYNA. The results of FE-simulations are in good agreement with the experimental result. After then, to construct rule base in progressive blanking process, FE-simulation has been performed using a simple model. Based on this result rule base is set up and then the blanking order of inner lead is rearranged. Consequently, from the results of FE-simulation using suggested method in this paper, it is possible to predict the shift of lead to manufacture high precision lead frame in progressive blanking process. The proposed method can give more systematic and economically feasible means for designing progressive blanking process.

Development of An Optimal Layout Design System in Multihole Blanking Process

Sun-Bong Lee,Dong-Hwan Kim,Byung-Min Kim 한국정밀공학회 2004 International Journal of Precision Engineering and Vol.5 No.1

The blanking of thin sheet metal using progressive dies is an important process on production of precision electronic machine parts such as IC leadframe. This paper summarizes the results of simulating the progressive blanking process by means of LS/DYNA. In order to verify the influence of blanking order on the final lead profile and deformed configuration, simulation technique has been proposed and analyzed using a commercial FEM code, LS/DYNA. The results of FE-simulations are in good agreement with the experimental result. After then, to construct rule base in progressive blanking process, FE-simulation has been performed using a simple model. Based on this result rule base is set up and then the blanking order of inner lead is rearranged. Consequently, from the results of FE-simulation using suggested method in this paper, it is possible to predict the shift of lead to manufacture high precision leadframe in progressive blanking process. The proposed method can give more systematic and economically feasible means for designing progressive blanking process.

센터필라의 핫스템핑 공정에서의 블랭크 형상 최적화

최홍석(Hongseok Choi),김병민(Byungmin Kim),강충길(Chunggil Kang),하세윤(Seyun Ha),이동휘(Donghui Lee) 한국자동차공학회 2009 한국자동차공학회 학술대회 및 전시회 Vol.2009 No.11

Automotive companies are pursuing to use the ultra advanced high strength steels(UAHSS) for improving fuel efficiency and crashworthiness in body panels and structures. Hot stamping process using martensitic phase transformation of austenized blank has been developed to obtain the strength above 1.5GPa with high dimensional accuracy and formability. In this study, the optimization of blank shape for hot stamping has been performed to reduce trial-and error method in development the center pillar of the automotive structural panel. In order to optimize blank shape which is one of the most important factors in hot stamping process, inverse analysis was performed to obtain initial blank shape for center pillar by the conventional stamping code, J-Stamp.Optimal blank shape has been determined by thermo-mechanical simulation considered to friction, holding force and tool shape using compensation the error between deformed path and target contour. furthermore, wrinkle at bottom region of center pillar, assembled with sill side, were significantly reduced by applying optimized drawbead. In this study, it can be established that blank optimization method for hot stamping of center pillar, an automotive structural part, in order to reduce shape error, wrinkle and fracture.

실험 계획법을 사용한 B-Pillar 성형공정에서 블랭크 형상 최적화

윤형원,최용석,이창환,Youn, Hyung-Won,Choi, Yong-seok,Lee, Chang-Whan 한국금형공학회 2021 한국금형공학회지 Vol.15 No.2

The shape of the blank greatly affects the formability and quality of the product after the stamping process. In this study, the geometry of the B-Pillar blank in the stamping process was optimized using design of experiments. The geometry of the blank for the B-pillar was simplified with the two length values and two radius values. The effects of design variables were studied through the Design of experiments. The stamping process of the B-pillar was predicted with the Finite Element Analysis (FEA). The optimized blank geometry was obtained. It results in the reduced maximum equivalent plastic strain. The local necking and the wrinkling did not occurred with the optimized blank geometry.