weld metal hydrogen cracking in transmission pipelines construction

developments of high strength steels for natural gas pipelines has been in the forefront of steelmaking and rolling technology in the past decades however parallel to such developments in steel industry the welding technology especialy with regards to SMAW process which is still widely used in many projects has not evolved accoringly decreasing carbon equivalent has shifted the tendency of hydrogen cracking from HAZ to weld metal .hydrogen cracking due to its complex mechanism is affected by a range of interactive parameters experience and data gained from field welding of pipeline construction projects indicated that weld metal hydrogen cracking is related to welding position as it occurs more in 6 o'clock position of pipeline girth welds.

Keywords:

weld metal hydrogen cracking , pipelines , welding position