In this research work, finite element simulation and experimental investigation of Orbital welding process on stainless steel AISI 316 L with different process parameters are performed. For experimental study three process parameters viz. welding current, welding speed and standoff distance to get 9 dominating experimental sets according to L-9 orthogonal array for each Orbital and TIG welding. Temperature and Tensile strength during the welding process are taken as an output parameter. Weld zone and defect of welding are checked by Boroscope. Tensile tests are performed on all welded pipe to determine the tensile strength and elongation. Optimization of the process parameter is done using TAGUCHI and ANOVA through MINITAB software. The optimum values of input parameters for temperature distribution during orbital welding are 40A current, 0.72 mm/s welding speed and 1.8 mm standoff distance. It is observed that welding current affects the temperature distribution maximum 49.83% followed by a welding speed of 31.53%. Standoff distance has a minimum effect viz. only 8.83%. The optimum values for input parameters for tensile strength during Orbital welding are 40A current, 1.08 mm/s welding speed and 1.6 mm standoff distance and welding speed affect the tensile strength maximum 35.19% followed by welding current 21.23%. Standoff distance has a minimum affect only 7.97%. For numerical study, the 3D model is prepared with orbital welding boundary conditions. The complete orbital welding process is simulated using ANSYS APDL software to predict temperature distribution and residual stress in the butt welded pipe. The average error is of the order of 8.2% hence the simulated environment created for Orbital welding can be used to predict the temperature and other values for any other material with other welding parameters. The paper ends with a comparison of experimental temperature with simulated temperature and tensile strength of orbital and TIG welding process.
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