ASTM A928 "as welded" pipe (HT-O)
ASTM A928 "as welded" pipe (HT-O)
(OP)
Hi everybody, the question:
for a super duplex steel pipe (24"-36") as per ASTM A928 CL.1 UNS S32760, a vendor specifies that:
"The pipes with OD > 600 mm will be delivered in the "as welded" conditions (HT-O)".
Any suggestions about what it implies? Are they giving me something less or something more?
I'm still in a bid phase, so I can align all the vendors on similar basis.
I think this is an interesting question for everybody. Thank you for your help anyway.
for a super duplex steel pipe (24"-36") as per ASTM A928 CL.1 UNS S32760, a vendor specifies that:
"The pipes with OD > 600 mm will be delivered in the "as welded" conditions (HT-O)".
Any suggestions about what it implies? Are they giving me something less or something more?
I'm still in a bid phase, so I can align all the vendors on similar basis.
I think this is an interesting question for everybody. Thank you for your help anyway.





RE: ASTM A928 "as welded" pipe (HT-O)
I think you would be responsible for final HT and properties.
I had came to the same conclusion in my case, and decided to find another vendor.
thread794-308067: 2205 Pipe HT-0
Regards,
Mike
RE: ASTM A928 "as welded" pipe (HT-O)
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04
RE: ASTM A928 "as welded" pipe (HT-O)
If you review ASTM A 928 it means no heat treatment after welding. In this specification you as the purchaser have options;
Under 6.3 you either specifically state in your PO acceptance for HT-O pipe (no heat treatment) OR as per this specification, the default requirements is heat treated pipe per the requirements in Table 2 of this specification.
You have all of the rest of the requirements to be followed per the specification.
Do you have a copy of A 928???
RE: ASTM A928 "as welded" pipe (HT-O)
I have a copy of A 928. It clearly states that heat treatment is mandatory after welding. It is a purchaser option to accept in "as welded" condition.
My doubt is about pipe dimensions and thicknesses: we are talking of UNS S32760 pipe with NPS 24-thk 30,96mm and NPS 36-thk 42mm.
The strains are relevant during forming so I deem that heat treatment is important after welding in order to relieve steel.
My doubt remain about to declare "not acceptable" the technical offer of a vendor that deliveres pipe as "HT-O".
RE: ASTM A928 "as welded" pipe (HT-O)
As long as you did not state in your proposal or purchase order or contract that you waive the post forming and welding heat treatment requirements as per A 928, the material must be supplied heat treated.
If the vendor is simply providing a proposal or quote and no contract commitment has been made to accept unheat treated material, your refusal of material is based on technical concerns with dimensional tolerances and residual forming strains. Am I missing something - if not reject this as welded option.
RE: ASTM A928 "as welded" pipe (HT-O)
Shell MESC 74/022_2010 states that: "pipe shall be in the solution-annealed condition".
So, as per Shell, pipe in as-rolled condition cannot be accepted.
Guys, this will be a very good point during my "trial" in front of proposal manager!
RE: ASTM A928 "as welded" pipe (HT-O)
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04
RE: ASTM A928 "as welded" pipe (HT-O)
Regardless. Forming solution annealed plate into pipe results in residual cold/warm forming strains within the pipe that could have deleterious effects on corrosion performance in service.
RE: ASTM A928 "as welded" pipe (HT-O)
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04