Welding deformation analysis based on improved equivalent strain method to cover external constraint during cooling stage

Abstract In the present study, external restraints imposed normal to the plate during the cooling stage were determined to be effective for reduction of the angular distortion of butt-welded or fillet-welded plate. A welding analysis model under external force during the cooling stage was idealized as a prismatic member subjected to pure bending. The external restraint was represented by vertical force on both sides of the work piece and bending stress forms in the transverse direction. The additional bending stress distribution across the plate thickness was reflected in the improved inherent strain model, and a set of inherent strain charts with different levels of bending stress were newly calculated. From an elastic linear FE analysis using the inherent strain values taken from the chart and comparing them with those from a 3D thermal elasto-plastic FE analysis, welding deformation can be calculated.

[1]  L. Tall.  Residual stresses in welded plates - a theoretical study, No. 235 (64-1). Presented at the Spring Meeting of the AWS in Dallas, (September 1961). , 1961 .

[2]  Yukio Ueda,et al.  Prediction of Welding Deformation and Residual Stress by Elastic FEM Based on Inherent Strain , 1996 .

[3]  Dae-Eun Ko,et al.  Determination of Inherent Strain Regions to Estimate Plate Deformation by Line Heating , 2002 .

[4]  C. D. Jang,et al.  A Study on the Prediction and Control of Welding Deformations of Ship Hull Blocks , 2000 .

[5]  P. Tekriwal,et al.  Transient and Residual Thermal Strain-Stress Analysis of GMAW , 1991 .

[6]  Yun-Sok Ha,et al.  Analysis of Post Weld Deformation at HAZ by External Forces Based on Inherent Strain , 2006 .

[7]  Jang-Hyun Lee,et al.  Relations between Input Parameters and Residual Deformation in Line Heating process using Finite Element Analysis and Multi-Variate Analysis , 2002 .

[8]  Kazuyoshi Matsuoka.  An Analytical Method on Residual Stresses in Welded Built-Up Shell Structures , 1983 .

[9]  Toshiharu Nomoto,et al.  DEVELOPMENT OF SIMULATOR FOR PLATE BENDING BY LINE-HEATING , 1990 .

[10]  Chris Conrardy,et al.  Control of distortion in thin ship panels , 1997 .

[11]  Beom-Seon Jang,et al.  Welding deformation analysis based on improved equivalent strain method considering the effect of temperature gradients , 2015 .

[12]  J. Goldak,et al.  A new finite element model for welding heat sources , 1984 .

[13]  Toshiharu Nomoto,et al.  Studies on Thermal Elastic-Plastic Problems (2 nd Report) , 1971 .

[14]  Yun-Sok Ha,et al.  Development of Thermal Distortion Analysis Method on Large Shell Structure Using Inherent Strain as Boundary Condition , 2008 .

[15]  Yukio Ueda,et al.  Measuring Method for Residual Stresses in Explosively Clad Plates and a Method of Residual Stress Reduction , 1996 .

[16]  Seung Il Seo,et al.  A Study on the Prediction of Deformations of Welded Ship Structures , 1999 .

[17]  C. M. Adams.  COOLING RATES AND PEAK TEMPERATURES IN FUSION WELDING , 1958 .

[18]  K Masubuchi,et al.  ANALYSIS OF THERMAL STRESSES AND METAL MOVEMENTS OF WELDMENTS: A BASIC STUDY TOWARD COMPUTER-AIDED ANALYSIS AND CONTROL OF WELDED STRUCTURES , 1975 .

[19]  Dr.-Ing. habil. Dieter Radaj.  Welding residual stress and distortion , 1992 .

[20]  C. D. Jang,et al.  Prediction of Welding Deformation of Ship Hull Blocks , 2003 .

[21]  Yong Tae Kim,et al.  Determination of Optimal Heating Conditions In Line Heating Process With Weaving Motions , 2006 .

[22]  Yukio Ueda,et al.  Compressive Ultimate Strength of Rectangular Plates with Initial Imperfections due to Welding (2 nd Report) , 1980 .

[23]  C. Jang,et al.  A simplified method to estimate longitudinal deformations of built-up beams due to welding and heating , 1995 .

[24]  Seung Il Seo,et al.  A study on the prediction of deformations of plates due to line heating using a simplified thermal elasto-plastic analysis , 1997 .

[25]  Chang Doo Jang,et al.  Welding Distortion Analysis of Hull Blocks using Equivalent Load Method Based on Inherent Strain , 2012 .