preheat & post weld heat treatment of SA-387 Gr 11 Class 2 ( 1 1/4 Chrome-moly) material
preheat & post weld heat treatment of SA-387 Gr 11 Class 2 ( 1 1/4 Chrome-moly) material
(OP)
What is required for preheating and post weld heat treatment of 1 1/4 Chrome-moly material?





RE: preheat & post weld heat treatment of SA-387 Gr 11 Class 2 ( 1 1/4 Chrome-moly) material
RE: preheat & post weld heat treatment of SA-387 Gr 11 Class 2 ( 1 1/4 Chrome-moly) material
RE: preheat & post weld heat treatment of SA-387 Gr 11 Class 2 ( 1 1/4 Chrome-moly) material
Regards,
Mike
RE: preheat & post weld heat treatment of SA-387 Gr 11 Class 2 ( 1 1/4 Chrome-moly) material
RE: preheat & post weld heat treatment of SA-387 Gr 11 Class 2 ( 1 1/4 Chrome-moly) material
Do not take this as definitive, your weld procedures, your service, your job specs (if any) may require different.
I doubt Sec VIII, Div 1 is going to require maintenance of pre-heat in any case, I think it is going to be mandated by metallurgy and desired properties.
Regards,
Mike
RE: preheat & post weld heat treatment of SA-387 Gr 11 Class 2 ( 1 1/4 Chrome-moly) material
RE: preheat & post weld heat treatment of SA-387 Gr 11 Class 2 ( 1 1/4 Chrome-moly) material
"Welded joints shall be heat treated immediately upon completion of welding.
The joint shall not be allowed to cool below 300 ºF (150 ºC) prior to heat
treatment. Alternately, the weld and adjacent metal may be heated to 600 ºF
(315 ºC), wrapped with insulation, and allowed to cool. Heat treatment may
then be performed later. "
The other source is API 934-E (1 1/4Cr-1/2Mo for above 825F), para 7.3.1 stating " During welding, the preheat temp shall be maintained until PWHT or dehydrogenation heat treatment (DHT) is performed in accordance with 7.3.2".
7.3.2 saying DHT to be 570F minimum for one hour minimum.
RE: preheat & post weld heat treatment of SA-387 Gr 11 Class 2 ( 1 1/4 Chrome-moly) material
RE: preheat & post weld heat treatment of SA-387 Gr 11 Class 2 ( 1 1/4 Chrome-moly) material
Years ago we had vessel ordered as class 2. However, the tensile and yield failed to meet the values, and re-certified as class 1.