A WELDING PROCEDURE WITH OPTIMIZED WELDING PARAMETERS TO PRODUCE DEFECT-FREE DISSIMILAR METAL WELDS OF THICKSECTIONS OF ALLOY 617 (ASME 2439) AND STAINLESS STEEL 304H CU(ASME 2328-1) FOR ADVANCED ULTRA SUPER CRITICAL POWER PLANTS

摘要

The invention relates to a welding procedure with optimized welding parameters to produce defect-free dissimilar metal weld joints of thick sections of Alloy 617 (ASME 2439) and stainless steel 304H Cu(ASME 2328-1) for Advanced Ultra Super Critical Power Plants comprising the steps of an edge preparation of the joinable plates; selecting the run-on and run-off plates made of stainless steel; selecting alloy 617 filler material for welding; using Argon as back purging gas; adapting conventional Gas Tungsten Arc Welding with parameters such as root pass and hot pass using 1.6 mm dia filler wire and remaining passes using 2.4 mm dia filler wire; without clamping arrangement for root pass and hot pass while during remaining passes, plates are clamped to restrict/minimize distortion; maintaining the inter-pass temperature maintained 150oC except for hot and root pass; cleaning by wire brush between passes to remove oxide debris, and using a pre-bend angle of 2o.