Report 1 efficacy of low carbon 11/4Cr-1/2Mo weld metal for repair welding of elevated temperature service exposed Cr-Mo components

摘要

The creep service suitability of low carbon (~0.030%) weld metal intended for controlled deposition repair welding of 1.25Cr-1/2Mo steel was studied. Results indicate weld metal stress rupture properties in excess of the virgin base metal ASTMdata base minimum. The tensile behavior of the weld metal in the as-welded and PWHT condition is in accordance with ASTM A387 Grade 11 Class 1. The toughness of the low carbon weld metal in the as-welded and PWHT condition is greater than that normallyindustrially specified. Following determination of the suitability of stress rupture properties of the low carbon weld metal, weld repair of service exposed full-scale components was carried out using controlled deposition procedures. Full thicknesscross-weld specimen stress rupture testing revealed that the repaired weldment behavior is equivalent to, or better than, the service exposed weldment and rupture life exceeds the ASTM base metal minimums in the as-welded condition and the life is greater than the ASTM mean in the PWHT condition. Thus, it is evident that repair weld behavior using low carbon consumables and controlled deposition procedures is suitable for elevated temperature applications.