Investigation of residual stresses and distortion in welded pipe-flange joint of different classes

Pipe and flange joints are commonly used in petrochemical, nuclear and process industry. Welding produces residual stresses and distortion, which has detrimental effect on structure integrity and service performance of the welded pipe joints. The objective of this study is to investigate residual stresses and distortion during Gas Metal Arc Welding of pipe of schedule 40, nominal diameter 200mm with different ANSI flanges of class # 150, 300, 600, 900, 1500, and 2500). Welding parameters includingvoltage, current and heat input are selected based on literature available. Behavior of flanges of different classes is discussed. Finite element methodology presented can be helpful for developing welding procedures for a range of pipe flange welded joint sizes for controlled residual stresses and deformations i.e. for optimized performance during bolt up and operating conditions