• Title, Summary, Keyword: Springback

Search Result 234, Processing Time 0.04 seconds

A Study on the Applying CAD of Springback Revision Value by Design Analysis (설계해석에 의한 SPRINGBACK 보정값 CAD 적용에 관한 연구)

  • Lee J. M.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • /
    • pp.312-317
    • /
    • 2005
  • In this study, using the stamping, analysis program, PAM STAMP, applied to the drawing result of springback analysis and draw analysis with applying on the best design planning as many times simulations from the initial stage of the die developing of automotive panels. Especially, after inspecting the design method with stamping analysis and springback analysis, write about the die development examples, using CADCEUS which is the software revising the amount of springback.

  • PDF

Multi Stage Simulations for Autobody Member Part (자동차 멤버 부품의 다공정 성형해석)

  • Park C.D.;Kim B.M.;Chung W.J.
    • Transactions of Materials Processing
    • /
    • v.15 no.4
    • /
    • pp.281-288
    • /
    • 2006
  • Most of automobile member parts experience severe springback problems because of their complicated shape and high yielding strength. Now it becomes imperative to develop an effective method to resolve these problems. However, there remain several obstacles to get accurate estimation of dimensional shape. Especially the effective algorithms to simulate sheet metal forming processes including drawing, trimming, flanging and springback is demanded for the multi stage simulation of automobile member parts. In this study, for the purpose of accurate springback calculation, a simulation program which is robust in springback analysis is developed. Favorable enhancement in computation time for springback analysis by using latest equation solving technique and robust solution convergence by continuation method are achieved with the program. In analysis, the multi processes of rear side member are simulated to verify the system. For the evaluation of springback accuracy practically, all conditions including boundary conditions for springback analysis and inspection conditions for dimensional accuracy are applied. The springback results of simulations show good agreement with the experiments.

Compensation Design to Reduce Springback in Sheet Metal Forming of 1.2GPa Ultra High Strength Steel (1.2GPa급 강판 판재 성형에서 스프링백 감소를 위한 금형 보상 설계)

  • Kwon, S.H.;Lee, H.S.;Lee, Y.S.;Kim, S.W.;Jung, C.Y.;Hong, S.
    • Transactions of Materials Processing
    • /
    • v.25 no.5
    • /
    • pp.301-305
    • /
    • 2016
  • The manual modification of stamping die has widely been used in order to reduce springback after sheet metal forming. When UHSS (Ultra High Strength Steel) is used in sheet metal forming, the die design considering springback compensation is more difficult because higher strength sheet has more springback. In this study, the optimization method was used in order to design die geometry considering springback compensation after forming of 1.2GPa UHSS. Die geometries were defined as design variables and the springback distance from the die surface was conducted as object function in optimization process. The optimized die geometry considering springback compensation was performed using finite element and optimization analysis. The simulation results such as thickness distribution and springback amount were compared with measured data using 3D optical measurement system (GOM ARGUS, ATOS). And the prediction of springback amount showed a good agreement within test results.

A Study of the Springback Reduction in Aluminium Sheet Forming Using Response Surface Method (반응표면분석법을 이용한 알루미늄 판재 성형공정의 스프링백 저감에 관한 연구)

  • 양재봉;전병희;오수익
    • Transactions of Materials Processing
    • /
    • v.9 no.5
    • /
    • pp.526-532
    • /
    • 2000
  • Springback simulation is receiving increasing attention throughout the automotive industry and the academic world. The knowledge of the real springback of stamped parts can help the stamping technicians to modify the process parameters or die geometry in order to reduce the shape defect. This paper presents the results of springback simulation after aluminium square cup deep drawing and trimming simulation, and results of springback optimization using response surface method.

  • PDF

A study on excavator front support parts to minimize springback defects (굴삭기 Front Support 부품 뒤틀림 결함 최소화 방안 도출)

  • Jeon, Yong-Jun;Heo, Young-Moo;Lee, Ha-Sung;Kim, Dong-Earn
    • Journal of the Korea Society of Die & Mold Engineering
    • /
    • v.12 no.2
    • /
    • pp.40-45
    • /
    • 2018
  • Recently, in construction equipment machinery production, development has focused on environmentally-friendly functions to improve existing production capacity. For excavators as well, emphasis has been placed on response to environmental regulations, miniaturization, and noise reduction, while technology is being developed considering cost reduction and safety.Accordingly, the front support, an inner reinforcement part of the excavator, as well as high-strength steel plates to improve safety and reduce weight, are being applied.However, in the case of high-strength materials, Springback occurs in the final formed part due to high residual stress during product forming. Derivation of a forming or product shaping process to reduce springback is needed. Accordingly, regarding the front support, an inner reinforcement part of the excavator, this study derived a method to improve springback and secure shape stiffness through analysis of the springback occurrence rate and springback causes through a forming analysis.As for the results of analyzing the springback occurrence rate of existing products through forming analysis, springback of -22.6 mm < z < 27.35 mm occurred on the z-axis, and it was confirmed that springback occurred due to the stiffness reinforcing bead of the upper and middle parts of the product.To control product residual stress and springback, we confirmed a tendency of springback reduction through local pre-cutting and stiffness reinforcement bead relocation.In the local pre-cutting model, springback was slightly reduced by 5.3% compared with the existing model, an insignificant reduction effect. In the stiffness reinforcement bead relocation model, when an X-shaped stiffness reinforcement bead was added to each corner portion of the product, springback was reduced by at least 80%.The X-shaped bead addition model was selected as the springback reduction model, and the level of stiffness compared to the existing model was confirmed through a structural analysis.The X-shaped bead additional model showed a stress springback of 90% and springback reduction of 7.4% compared with the existing model, indicating that springback and stiffness will be reinforced.

Study on the Springback Reduction of Automotive Advanced High Strength Steel Panel (자동차 초고강도 강판 패널의 스프링백 저감에 관한 연구)

  • Kim, B.G.;Lee, I.S.;Keum, Y.T.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • /
    • pp.191-194
    • /
    • 2009
  • Very big springback in advanced high strength steel(AHSS) sheets invokes undesired shape defects, which can be eliminated by the tool surface correction method or the forming process control method. Since the springback reduction by controlling the forming process is limited, in this study, the die correction method which finds die correction from the relationship between die design variable and springback is introduced to achieve springback reduction and is applied to the automotive side rail to reduce the springback of 75.8% within the assembly limit of 1 mm.

  • PDF

A study on the Effects of Input Parameters on Springback Prediction Accuracy (스프링백 해석 정도 향상을 위한 입력조건에 관한 연구)

  • Han, Y.S.;Oh, S.W.;Choi, K.Y.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • /
    • pp.285-288
    • /
    • 2007
  • The use of commercial finite element analysis software to perform the entire process analysis and springback analysis has increased fast for last decade. Pamstamp2G is one of commercial software to be used widely in the world but it has still not been perfected in the springback prediction accuracy. We must select the combination of input parameters for the highest springback prediction accuracy in Pamstamp2G because springback prediction accuracy is sensitive to input parameters. Then we study the affect of input parameters to use member part for acquiring high springback prediction accuracy in Pamstamp2G. First, we choose important four parameters which are adaptive mesh level at drawing stage and cam flange stage, Gauss integration point number through the thickness and cam offset on basis of experiment. Second, we make a orthogonal array table L82[(7)] which is consist of 8 cases to be combined 4 input parameters, compare to tryout result and select main factors after analyzing affect factors of input parameters by Taguchi's method in 6 sigma. Third, we simulate after changing more detail the conditions of parameters to have big affect. At last, we find the best combination of input parameters for the highest springback prediction accuracy in Pamstamp2G. The results of the study provide the selection of input parameters to Pamstamp2G users who want to Increase the springback prediction accuracy.

  • PDF

Investigation of Shape Accuracy in the Forming of a Thin-walled S-rail with Classification of Springback Modes (스프링백 모드분류를 통한 박판 S-rail 성형공정의 형상정밀도 고찰)

  • Jung, D.G.;Kim, S.H.;Kim, M.S.;Lee, T.G.;Kim, H.K.
    • Transactions of Materials Processing
    • /
    • v.22 no.8
    • /
    • pp.477-485
    • /
    • 2013
  • This paper aims to evaluate quantitatively the springback characteristics that evolve in the sheet metal forming of an S-rail in order to understand the reasons of shape inaccuracy and to find a remedy. The geometrical springback is classified into six modes: angle change of punch and die shoulders, wall curl, ridge curl, section twist, and axial twist. The measuring method for each springback mode is suggested and quantitative measurements were made to determine the tendency towards shape accuracy. Forming experiments were conducted with four types of steel sheets that have different tensile strengths, which were 340MPa, 440MPa, 590MPa and 780MPa, in order to evaluate the effect of the tensile strength and the bead shape on the springback behavior. Springback tendencies show that they are greatly affected by the tensile strength of the sheet and the shape of the tools. Almost all springback modes except the section twist and the axial twist show a linearly increasing trend as the tensile strength of the sheet increases. The results can be used as basic data for design and for compensation of the press die geometry when forming high strength steels which exhibit large amounts of springback.

Analysis of Springback of Sheet Metal(II): Experimental Validation of Analytical Model (박판재의 스프링백 해석(II)-해석모델의 실험적 검증)

  • Lee, Jae-Ho;Kim, Dong-Woo;Sohn, Sung-Man;Lee, Mun-Yong;Moon, Young-Hoon
    • Transactions of Materials Processing
    • /
    • v.16 no.7
    • /
    • pp.516-520
    • /
    • 2007
  • As the springback of sheet metal during unloading nay cause deviation from a desired shape, accurate prediction of springback is essential for the design of sheet stamping operations. On the removal of the applied load the specimen loses its elastic strain by contracting around the contour of the block, the radius $\rho$ can be determined by the residual differential strain. Therefore in this study the springback estimated by the residual differential strain is experimentally validated through the comparison with those obtained by U-bending test. The springback characteristics of two analytical models are also estimated at various processing conditions such as thickness, curvature of radius and drawing strain. The model based on residual differential strain has an applied transition strain where the springback undergoes a dramatic decrease. Both models show that springback decreases with increased strip thickness and with decreased radius of curvature. For no applied tension, the model based on residual differential strain predicts more springback as compared to the moment based model.

Study on the Springback Reduction of Automotive Advanced High Strength Steel Panel (자동차 초고강도 강판 패널의 스프링백 저감에 관한 연구)

  • Kim, B.G.;Lee, I.S.;Keum, Y.T.
    • Transactions of Materials Processing
    • /
    • v.18 no.6
    • /
    • pp.488-493
    • /
    • 2009
  • The very big springback of advanced high strength steel(AHSS) sheets invokes undesired shape defects, which can be generally eliminated by die correction or process parameter control. The springback reduction by controlling the forming process parameters is easy for the application, but limited for the bulky achievement. In this study, the effective die correction method, which obtains the modification of tool shape from the relationship between die design variable and springback, is introduced and is applied to the TWB tool of automotive side rail to show the validity and usefulness. Among the die correction trials repeatedly performed, the first trial is carried out by correcting the tool shape to the opposite direction to the springbacks of several tool sections. Next trials are done by extrapolating the springbacks of among the original tool uncorrected and the tools corrected negative amounts of the springback and by finding tool shapes without springbacks. After the angle of side wall and radius of curvature of horizontal bottom floor are chosen as design variables in the tool design of side rail, the tool shape is corrected 3 times. The accuracy of final shape within the assembly limit of 1mm and the springback reduction of 75.8% compared to the uncorrected tool are achieved.