Is backweld allowed to correct root bead welding defects or misalignment on the inside (process side) of pipe?

Asked by jakangaru 5 years, 9 months ago | 1 Answers


1 Answer

0
franchaze 5 years, 9 months ago

Backwelding should not be permitted unless it meets at least one of the following conditions:

  • With proper PWHT at a sufficiently high temperature and adequate holding time to reduce residual stresses and lower hardnesses to less than 248 HV10 (Diamond Pyramid).
  • The adequacy of the PWHT procedure should be demonstrated during welding procedure qualification testing
  • By performing the backweld repair before the second pass is applied