• 제목/요약/키워드: bending analysis

검색결과 3,424건 처리시간 0.027초

유한요소해석을 이용한 박판 벤딩용 CO2 레이저 성형기 제작 (Production of CO2 Laser Forming Machine for Bending of Sheet Metal Using the FE-Analysis)

  • 고대철;이찬주;김병민
    • 소성∙가공
    • /
    • 제15권4호
    • /
    • pp.319-325
    • /
    • 2006
  • The laser forming process is a new flexible forming process without forming tools and external force, which is applied to various fields of industry. Especially, applications of the laser forming process focused on cutting, welding and marking process. In this paper, the laser bending process of sheet metal which is heated by laser beam and formed by internal stress is simulated by using thermo elastic-plastic analysis model. Based on the result of FE-analysis, the laser bending machine is made to obtain reliable data for sheet bending. Under the same condition as FE-analysis, the laser bending experiment has been performed to ver 펴 the result of FE-analysis and good agreement has been obtained between FE-analysis and experiments. Additional laser bending experiments have been performed to evaluate the laser bending machine.

저탄소강판을 이용한 굽힘 가공에서 발생하는 꺾임 현상에 대한 발생기구 해석 (Analysis on the Mechanism of Fluting in the Bending of Low Carbon Steels)

  • 박기철;윤정봉
    • 소성∙가공
    • /
    • 제16권4호
    • /
    • pp.317-322
    • /
    • 2007
  • In order to investigate the cause and condition of fluting in tangential bending of low carbon steel sheet, an analytic analysis, an experiment and a series of finite element analysis for bending process were done. The fluting in bended sheet was related with the yield point elongation of material. Due to the yield point elongation, unstable plastic hinge was occurred in course of bending of elastic perfectly plastic sheet. According to the analysis and computational results, lower yield point elongation than 5% was required to prevent fluting in 0.5-0.6t sheet in $15{\sim}25mm$ radius bending. The tendency of fluting occurrence was reduced as decreasing the radius of bending, increasing thickness of bended sheet, and removing irregularity in sheet and bending processes.

굽힘이력을 고려한 딥드로잉공정의 유한요소역해석 (Finite Element Inverse Analysis of the Deep Drawing Process Considering Bending History)

  • 허지향;윤종헌;바오이동;허훈
    • 소성∙가공
    • /
    • 제16권8호
    • /
    • pp.590-595
    • /
    • 2007
  • This paper introduces a new approach to take account of bending history in finite element inverse analysis during sheet metal forming process. A modified membrane element was adopted for finite element inverse analysis so that bending-unbending energy was additionally imposed in the total plastic energy, predicting bending-unbending regions using the geometry of the final shape and tools. An algorithm was applied to a cylindrical cup deep drawing process. The blank shape and the distribution of the thickness strain were compared with those obtained from the incremental finite element analysis in order to evaluate the effect of the bending history. The algorithm reduced the difference between the results of the inverse analysis from those of the incremental analysis due to bending history. The analysis was also carried out with the variation of the thickness of the initial blank to investigate the effect of bending deformation. The results showed that the difference was remarkably reduced as the thickness of the initial blank increased. This indicates that the finite element inverse analysis cooperated with the suggested scheme is useful to obtain more accurate results, especially when bending effects are significant.

벨로우즈형 신축관이음의 휨각도 예측 및 이를 이용한 배관계의 안정성 해석 (Prediction of Bending Angle of Bellows and Stability Analysis of Pipeline Using the Prediction)

  • 손인수
    • 한국산업융합학회 논문집
    • /
    • 제25권5호
    • /
    • pp.827-833
    • /
    • 2022
  • In this study, the prediction of the bending angle for the 350 A bellows-type expansion joints and the structural stability according to the load were determined. The stability of the 2km piping system was predicted by applying the allowable bending angle of the expansion pipe joint obtained from the analysis. The maximum bending angle was calculated through bending analysis of the bellows-type expansion joints, and the maximum bending angle by numerical calculation was about 1.8°, and the maximum bending angle of the bellows obtained by comparing the allowable strength of the material was about 0. 22°. This angle was very stable compared to the allowable bending angle (3°) of the expansion pipe joint regulation. By applying the maximum bending angle, the allowable maximum deflection of the 2 km pipe was about 3.8 m. When the seismic load was considered using regression analysis, the maximum deflection of the 2km pipe was about 142.3mm, and it was confirmed that the bellows-type expansion joints and the deflection were stable compared to the allowable maximum deflection of the pipe system. These research results are expected to present design and analysis guidelines for the construction of piping and the development of bellows systems, and to be used as basic data for systematic research.

3차원 Bending Machine 설계에 관한 연구 (A Study on the Design of Three-Dimensional Bending Machine)

  • 이춘만;임상헌;박동근
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2003년도 추계학술대회
    • /
    • pp.1852-1857
    • /
    • 2003
  • This study is concerned about the development of three-dimensional bending machine for heat exchanger. Recently, three-dimensional bending is required for various heat exchanger. The purpose of this study is design of three-dimensional bending machine by analysis of bending process and structural analysis simulation. The analysis is carried out by FEM simulation using DEFORM and CATIA V5 software. The copper-tube is modeled by shell elements and the machine is modeled by placing proper shell and solid finite elements and fictitious mass properties to represent the real one. The final results of analysis are applied to the design of three-dimensional bending machine and the machine is successfully developed.

  • PDF

Bending moments in raft of a piled raft system using Winkler analysis

  • Jamil, Irfan;Ahmad, Irshad
    • Geomechanics and Engineering
    • /
    • 제18권1호
    • /
    • pp.41-48
    • /
    • 2019
  • Bending moments in the raft of a pile raft system is affected by pile-pile interaction and pile-raft interaction, amongst other factors. Three-Dimensional finite element program has to be used to evaluate these bending moments. Winkler type analysis is easy to use but it however ignores these interactions. This paper proposes a very simplified and novel method for finding bending moments in raft of a piled raft based on Winkler type where raft is supported on bed of springs considering pile-pile and pile-raft interaction entitled as "Winkler model for piled raft (WMPR)" The pile and raft spring stiffness are based on load share between pile and raft and average pile raft settlement proposed by Randolph (1994). To verify the results of WMPR, raft bending moments are compared with those obtained from PLAXIS 3D software. A total of sixty analysis have Performed varying different parameters. It is found that raft bending moments obtained from WMPR closely match with bending moments obtained from PLAXIS 3D. A comparison of bending moments ignoring any interaction in Winkler model is also made with PLAXIS-3D, which results in large difference of bending moments. Finally, bending moment results from eight different methods are compared with WMPR for a case study. The WMPR, though, a simple method yielded comparable raft bending moments with the most accurate analysis.

저탄소강판을 이용한 굽힘 가공에서 발생하는 꺽임현상에 대한 발생 기구 해석 (Analysis on the Mechanism of Fluting in the Bending of Low Carbon Steel Sheets)

  • 박기철;윤정봉
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2007년도 춘계학술대회 논문집
    • /
    • pp.336-339
    • /
    • 2007
  • In order to investigate the cause of fluting in tangential bending of low carbon steel sheet, an analytic analysis, an experiment and a series of finite element analysis for bending process were done. The fluting in bended sheet was due to the yield point elongation of material. Due to the yield point elongation, unstable plastic hinge was occurred in course of bending of elastic perfectly plastic sheet. According to the analysis and computational results, lower yield point elongation than 5% was required to prevent fluting in $0.5{\sim}0.6t$ sheet in $15{\sim}20mm$ radius bending.

  • PDF

굽힘이력을 고려한 원형컵 딥드로잉공정의 유한요소역해석 (Finite Element Inverse Analysis of the Cylindrical Cup Deep Drawing Process Considering Bending History)

  • 허지향;윤종헌;바오이동;허훈
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2007년도 춘계학술대회 논문집
    • /
    • pp.340-343
    • /
    • 2007
  • This paper introduces a new approach to consider the bending history in finite element inverse analysis of the cylindrical cup drawing. A modified membrane element is adopted to add the bending-unbending energy to the total plastic energy on the bending-unbending region predicted from the geometry of the final shape and tools. The algorithm suggested was applied to a cylindrical cup deep drawing process. The blank shape and the distribution of the thickness strain are compared with those obtained from incremental finite element analysis. The comparison demonstrates the algorithm proposed reduces the difference between the results from inverse analysis and those from incremental analysis when the bending history is considered.

  • PDF

3 차원 벤딩 머신에서 정밀 성형을 위한 공정 개발에 관한 연구 (A study on the process for precision forming by 3-dimension bending machine)

  • 김현진;임상헌;이춘만
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2005년도 춘계학술대회 논문집
    • /
    • pp.1897-1900
    • /
    • 2005
  • The purpose of this study is to investigate the bending process for manufacturing of sound pipe by 3 dimension bending machine. The arbitrarily-bended pipe is widely used in a heat exchanger system. The pipe should be formed precisely for assembling of heat changer. And, spring back effect and variation of the pipe thickness should be controlled effectively. We described the change of spring back amount and thickness variation of the pipe according to the change of bending radius and bending angle by FEM analysis. The analysis is adopted the elasic-plastic analysis and contact analysis on MARC software.

  • PDF

굽힘효과를 고려한 박막 유한요소에 의한 단면 성형해석 (Sectional forming analysis by membrane finite elements considering bending effects)

  • 김준보;이광병;금영탁
    • 대한기계학회논문집A
    • /
    • 제22권3호
    • /
    • pp.493-503
    • /
    • 1998
  • The sectional forming analysis considering bending effects from the geometrically deformed shape of two linear membrane finite elements(called super element) was performed under plane strain assumption for analyzing forming processes of an arbitrarily shaped draw-die. For the evaluation of bending effects, the bending equivalent forces are calculated from the bending moment computed using the changes in the interior angle at the middle node of super element, and are agumented to the membrane stretch forces. In order to verify the validity of the bending formulation, the simulation results for the stretch, draw, and bend sections were compared with membrane analysis results and measurements.