Determination of grain size and resistance to corrosion of stainless steel welded pipes

Abstract

Discover problems of welds is not so easy from time to time. Specially, If welding was made in rough environmental conditions such as high temperature, humidity and dusty wind. It is necessary to provide good conditions to realize basic step of welding. For welding, have been used welding procedures specification and procedure qualification record. However, dificult conditions, documentations rightness or human errors are always here. Common weld defects like cracks, porosity, lack of penetration and distortion can compromise the strength of the base metal, as well as the integrity of the weld. According of site inspection, there were suspicion of intercrystalline corrosion, inclusions, leaker or segregation in root of weld, root weld stretches to the pipe inside, the welded pipes are not in axially level, the not proper surface treatment after welding and keep the intervals between single welds to not overheat the pipes.