This paper outlines the development and qualification of welding procedures for tangent attachment weld joints (TAWJ) with joint designs compliant with the Expansion Joint Manufacturers' Association (EJMA-2012) code.

The study was instigated by the imperative need for quality assurance in the manufacturing of double-structure two-ply ASTM B 443 INC 625 bellows (982 (OD) × 580 (L) mm) in SS316L sodium piping for technology development.

The bellows are designed for 11.2 bar and 530 °C. The qualification process meticulously considered several critical factors, including pressure-bearing fillet joints, dissimilar materials, dissimilar thicknesses, joint designs recommended by other codes for similar applications, and setting of testing variables for typical joint to meet welding qualification code and design requirements.

Welding procedure qualifications were carried out with various fit-up configurations, heat input and welding position required for actual fabrication. Gas Tungsten Arc Welding (GTAW) and ErNiCrMo-3 filler material is used and adopted during manufacture of bellows.

The manufactured bellow assembly qualified all the specified testing required for component qualification in sodium piping, including performance under high temperature sodium.

This article is shared by Shri Krishna Tripathi*, S.C.S.P. Kumar Krovvidi and G. Ramesh.