Structural Evaluation of a Butt-Welded Elbow End: A Simplified Procedure

Abstract

Explicit piping design procedures are not provided in theASME Code for structural evaluation of ovalization and fabrication effects at the butt-welded end of an elbow. This paper presents a conservative semi-analytical procedure that can be used with elastic as well as inelastic analysis to evaluate an elbow cross section welded to a straight pipe. The concept of carry-over factors is used to obtained ovalization stresses or strains at the elbow end. The stresses introduced by material and geometric nonuniformities in the fabrication process are then added to the ovalization stresses to complete structural evaluation of the girth butt-welded elbow joint.