ORBITAL TIG WELDING OF BOILER TUBES OF GRADE SA 213 T11 USING DEEP PENETRATION FLUX

摘要

A process for orbital TIG welding of boiler tubes of grade SA 213 T11 comprising the steps of: - cleaning of the joining surfaces of the tubes(1) to remove oxide films, oil coatings etc; - preparing the cleaned edges to have a square butt joint by machining; - fitting the tubes (1) to be joined properly at the joint area with zero gap; - applying deep penetration flux (2) on the joint area; - holding the tubes (1) to be joined in fixed position through clamps; - selecting a plurality of welding parameters on pendant (6) and - welding the tubes. The welding is carried out by keeping the tubes stationary and rotating the welding head (3) around the joint to complete the weld, and is completed in a single pass with full penetration.