Post-weld Stress Relief
Post-weld Stress Relief
(OP)
Anyone has experince with post-weld stress relief for carbon steel piping welded to a casting part? What is the heating temperature? and holding time?
I would also appreciate if any references could be found.
Thanks in advance.
I would also appreciate if any references could be found.
Thanks in advance.





RE: Post-weld Stress Relief
RE: Post-weld Stress Relief
Casting material, CS A216 WCB or A352 LCB. Pipes, A106 B, Sch 80, sizes range from 1" to 3". Casting weld joint wall thickness: 0.5", bore to pipe.
Welds: 1" and 1 1/2", SW, 3", BW.
There are two purposes to carry out stress relief, 1] reduce internal stress; and 2] ensure the final dimensional tolerance of the assembly.
If you need more info, please let me know.
Thanks again.
Henry Kong
RE: Post-weld Stress Relief
To reduce the possibility of distortion from thermal gradients, place the welded component in a furnace that is at 600 deg F, and increase the temperature at increments of 450 deg F per hour until 1100 deg F is reached. Hold for 30 minutes, and ramp down at the same rate until 800 deg F is reached, cool in air.
RE: Post-weld Stress Relief
Further more, since the casting had already been heat treated most probably quenched, prior to welding, does the PWHT affect casting's mechanical properties? If so, does the whole assembly need to be heat treated again?
Thanks again,
Henry
RE: Post-weld Stress Relief
RE: Post-weld Stress Relief
Thank you so much metengr!
Henry Kong. PEng
Mechanical Engineer
QuestAir Technologies
kong@questairinc.com