Was PWHT done on this Pipe Weld?
Was PWHT done on this Pipe Weld?
(OP)
6" schedule 80 (0.432) pipe, circumferential weld. A106, probably grade B. Weld made in standard fashion, E7018 fill passes.
Side 1: Carbon equivalent (per IIW) = 0.30; maximum HAZ hardness = 185 HV1 (1kg) ~90HRB
Side 2: CE = 0.40; maximum HAZ hardness = 180 HV1 ~89HRB
Any opinions on whether this weld was PWHT (required for service, not by Code)?? I cannot decide.
Side 1: Carbon equivalent (per IIW) = 0.30; maximum HAZ hardness = 185 HV1 (1kg) ~90HRB
Side 2: CE = 0.40; maximum HAZ hardness = 180 HV1 ~89HRB
Any opinions on whether this weld was PWHT (required for service, not by Code)?? I cannot decide.
"If you don't have time to do the job right the first time, when are you going to find time to repair it?"





RE: Was PWHT done on this Pipe Weld?
Based on several EPRI documents related to CE affects (with values similar to SA 106 Gr B material) to establish new PWHT exemptions for ASME Boiler and Pressure Vessel Code for P-No 1 base materials, peak hardness of the weld HAZ for the 0.40 comparable CE value indicates PWHT was performed, rather than left as-welded.
Peak HAZ hardness values would be closer to 210 HV for the 0.30 CE base material and even slightly higher (225 HV) for the 0.40 CE base material, in the as welded condition.
RE: Was PWHT done on this Pipe Weld?
Do you have the EPRI document numbers (if they are free issue)? I have in my library # 1008277 from 2004, 1011535/2005 and 1013554/2006. The last of those appears the most helpful.
The only thing I can add is that the microstructure doesn't look as 'sharp' as an as-welded structure might (very a subjective impression and possibly quasi-scientific I know).
"If you don't have time to do the job right the first time, when are you going to find time to repair it?"
RE: Was PWHT done on this Pipe Weld?
RE: Was PWHT done on this Pipe Weld?
"If you don't have time to do the job right the first time, when are you going to find time to repair it?"
RE: Was PWHT done on this Pipe Weld?
What was the hardness of the unaffected base material? Your stated CE number for side 2 is on the higher end for what I have seen of SA 106 pipe material. Does this weld appear to be a SMAW or SAW weld?
Still lots of unanswered questions - which is why this type of internet chat can be inconclusive.
RE: Was PWHT done on this Pipe Weld?
Mean HAZ hardness ~165-170
Side 1 = pipe, CE = 0.30, BM ~165 HV1
Mean HAZ hardness ~170-175
The weld was definitely made by manual SMAW, 4 passes, 4 layers, although the root pass is unknown (most of it has corroded away in any event). The weld start is clearly evident at the bottom, and a wide weave was used in the cap pass, which is ~1 inch wide.
BTW, I am less dogmatically opposed to weaving than are many others. Provided the welder can reliably achieve sound deposits and limit interpass temps, there are tempering benefits to be gained from thinner, wider layers, especially for the low alloy grades.
"If you don't have time to do the job right the first time, when are you going to find time to repair it?"
RE: Was PWHT done on this Pipe Weld?