PURPOSE: To prevent release cracking under a high temp. and high pressure hydrogen environment, by a method wherein a build-up welding metal is cooled to a temp. not falling below 100°C on the way of cooling from a use temp. and held to the temp. between said temp. and heat treatment temp. after welding and subjected to hydrogen dispersing treatment before air cooling.

CONSTITUTION: A build-up welding metal is cooled to a temp. not falling below 100°C on the way of cooling from a use temp. and cooling is stopped. The cooled metal is held to the temp. between said temp. and heat treatment temp. after welding to be subjected to hydrogen dispersing treatment and thereafter cooled to an atmospheric temp. by air. By this method, the release cracking of the austenite stainless steel build-up welding metal based on low alloyed steel under a high temp. and high pressure hydrogen environment is prevented.