Prediction of the welding distortion of large steel structure with mechanical restraint using equivalent load methods
3
조회
0
다운로드
3
인용
0
참고문헌
키워드
초록
The design dimension may not be satisfactory at the final stage due to the welding during the assembly stage, leading to cutting or adding the components in large structure constructions. The productivity is depend on accuracy of the welding quality especially at assembly stage. Therefore, it is of utmost importance to decide the component dimension during each assembly stage considering the above situations during the designing stage by exactly predicting welding deformation before the welding is done. Further, if the system that predicts whether welding deformation is equipped, it is possible to take measures to reduce deformation through FE analysis, helping in saving time for correcting work by arresting the parts which are prone to having welding deformation. For the FE analysis to predict the deformation of a large steel structure, calculation time, modeling, constraints in each assembly stage and critical welding length have to be considered. In case of fillet welding deformation, around 300 mm is sufficient as a critical welding length of the specimen as proposed by the existing researches. However, the critical length in case of butt welding is around 1000 mm, which is far longer than that suggested in the existing researches. For the external constraint, which occurs as the geometry of structure is changed according to the assembly stage, constraint factor is drawn from the elastic FE analysis and test results, and the magnitude of equivalent force according to constraint is decided. The comparison study for the elastic FE analysis result and measurement for the large steel structure based on the above results reveals that the analysis results are in the range of 80e118% against measurement values, both matching each other well. Further, the deformation of fillet welding in the main plate among the total block occupies 66e89%, making welding deformation in the main plate far larger than the welding deformation in the longitudinal and transverse girders.
Abstract
The design dimension may not be satisfactory at the final stage due to the welding during the assembly stage, leading to cutting or adding the components in large structure constructions. The productivity is depend on accuracy of the welding quality especially at assembly stage. Therefore, it is of utmost importance to decide the component dimension during each assembly stage considering the above situations during the designing stage by exactly predicting welding deformation before the welding is done. Further, if the system that predicts whether welding deformation is equipped, it is possible to take measures to reduce deformation through FE analysis, helping in saving time for correcting work by arresting the parts which are prone to having welding deformation. For the FE analysis to predict the deformation of a large steel structure, calculation time, modeling, constraints in each assembly stage and critical welding length have to be considered. In case of fillet welding deformation, around 300 mm is sufficient as a critical welding length of the specimen as proposed by the existing researches. However, the critical length in case of butt welding is around 1000 mm, which is far longer than that suggested in the existing researches. For the external constraint, which occurs as the geometry of structure is changed according to the assembly stage, constraint factor is drawn from the elastic FE analysis and test results, and the magnitude of equivalent force according to constraint is decided. The comparison study for the elastic FE analysis result and measurement for the large steel structure based on the above results reveals that the analysis results are in the range of 80e118% against measurement values, both matching each other well. Further, the deformation of fillet welding in the main plate among the total block occupies 66e89%, making welding deformation in the main plate far larger than the welding deformation in the longitudinal and transverse girders.
참고문헌 (19)
- Deng, D., "Predicting welding deformation in thin plate panel structure by means of inherent strain and interface element", Sci. Technol. Weld. Join, 17(1), pp.13~21 (2012)
- 하윤석, "대형 용접구조물의 탄소성 열변형 해석을 위한 용접부의 변형률 경계조건에 관한 연구", 대한용접접합학회지, 29(4), pp.410~415 (2011), 대한용접접합학회
- 하윤석, "다층 맞대기용접의 쉘 요소 기반 변형해석법 개발", 대한용접접합학회지, 28(1), pp.54~59 (2010), 대한용접접합학회
- Ikushima, K., "A Study of Development of Prediction Method ofWelding Deformation and Stresses of Welded Structures Using Idealized Explicit FEM", Doctor, pp.2014
- 김태준, "Welding deformation analysis based on improved equivalent strain method considering the effect of temperature gradients", International Journal of Naval Architecture and Ocean Engineering, 7(1), pp.157~173 (2015), 대한조선학회
- 김태준, "Welding deformation analysis based on improved equivalent strain method to cover external constraint during cooling stage", International Journal of Naval Architecture and Ocean Engineering, 7(5), pp.805~816 (2015), 대한조선학회
- "MSC Patran PCL and Customisation, Version 9", MSC Software Corporation, ~ (1999)
- "NASTRAN Analysis Quick Reference Manual (Version 2008, r1)", MSC Software, ~
- Ninshu, Ma, "An accelerated explicit method with a two-stage computation scheme for transient thermal stress and welding deformation", Trans. JWRI, 44(1) (2015)
- Park, J. U., "Effects of mechanical constraints on angular distortion of welding joints", Sci. Technol. Weld. Join, 7(4), pp.232~239 (2002)
- Park, J. U., "Effects of mechanical constraints on angular distortion of welding joints", Sci. Technol. Weld. Join, 7(4), pp.232~240 (2002)
- Park, Jeong-Ung, "Residual stress measurement in an extra thick multipass weld using initial stress integrated inherent strain method", Mar. Struct, 39, pp.424~437 (2014)
- "PCL Reference Manual, Volume 1, Function Descriptions, Version 9", MSC Software Corporation, ~ (1999)
- "PCL Reference Manual, Volume 2, Code Examples, Version 9", MSC Software Corporation, ~ (1999)
- Sato, K., "Effect of welding conditions on residual stresses distributions and welding deformation in welded structures materials", J. Jpn. Weld. Soc, 45(4), pp.302~308 (1976)
- Shibahara, Masakazu, "Development of analytical method for welding mechanics using idealized explicit FEM", Trans. JWRI, 39(2), pp.384~386 (2010)
- Tsai, C. L., "Welding distortion of a thin-plate panel structure, welding journal", Res. Suppl, 78(15), pp.156s~165s (1999)
- Tsuji, I., "An analysis on transient stress and deformation of a steel strip subjected to local heating", Q. J. Jpn. Weld. Soc, 45(1), pp.36~41 (1976)
- Watanabe, Masaki, "External constraint and shrinkage of butt-welded joints in the erection of assemblies on building way", J. Zosen Kiokai, 104, pp.191~200 (1958)