A Review On The Problem Of Reheat Cracking In Nuclear Vessel Steels

TWI Industrial Member Report Summary 18/1976

By R E Dolby and G G Saunders

Background

Current knowledge on the problem of reheat cracking in thick walled nuclear vessels has been reviewed following a study of published and unpublished reports and discussions with experts in Europe, Scandinavia and the USA. The steels considered in the review include SA533 Grade B Class 1, SA508 Class 2, SA508 Class 3 and 22NiCrMo37.

Reheat cracking has been found in two locations (i) in the HAZ associated with internal stainless cladding and termed underclad cracking (ii) in the HAZ of structural welds and known as structural weld cracking. No reheat cracking in weld metal has been reported.