PRCI PR-185-9104

L51678e

Edison Welding Institute

This program completes a 2-year study investigating the effects of SMAW repair welding on the residual stress distribution and fracture toughness of pipeline girth welds. This second year of work, under contract PR-185-9104, has studied double part-wall, standard full-wall and modified full-wall repairs on GMA fabricated girth welds. The modified repair used a stringer bead technique in an effort to enhance the toughness of the repair region. The results of this study indicated the repair welds produced yield magnitude axial residual stresses on the inside and outside pipe surfaces. The hoop residual stresses were approximately equal to half-yield magnitude the inside surface while they were nearly zero in the weld on the outside surface of the pipe. The stress distributions were nearly identical regardless of the type of repair. Fracture toughness was reduced in the double part-wall and standard full-wall repairs. However, the modified full-wall repair produced toughness levels which exceeded the toughness of the original girth weld. This was attributed to grain refinement in the modified repair produced by the stringer bead technique.

Product Details

Published:

03/18/1993

Number of Pages:

83

File Size:

1 file , 3.6 MB