Hardness testing on existing PQR
Hardness testing on existing PQR
(OP)
Hello All,
I am currently on a project that the customer wants hardness testing done on existing PQR's. I have duplicated one of the original test coupons for a PQR, but I am having a hard time finding SA-285 Gr. C 3/8" thick for the second coupon, which was the original material and thickness used for approval. Does the material and thickness have to be identical to the original PQR or can I use a material with equal or greater properties?
Any help would be greatly appreciated.
I am currently on a project that the customer wants hardness testing done on existing PQR's. I have duplicated one of the original test coupons for a PQR, but I am having a hard time finding SA-285 Gr. C 3/8" thick for the second coupon, which was the original material and thickness used for approval. Does the material and thickness have to be identical to the original PQR or can I use a material with equal or greater properties?
Any help would be greatly appreciated.





RE: Hardness testing on existing PQR
The material should be the same specification (including heat treatment) if you intend to revise the existing PQR's to add hardness testing values. Why are you even doing this? Do you have a min/max hardness range that is acceptable for the application?
RE: Hardness testing on existing PQR
Just my $0.02.
RE: Hardness testing on existing PQR
Unless, impact testing is required or temper bead procedures are being qualified or there is a specific requirement for maximum hardness to avoid HAC, as in petrochemical applications, hardness testing should be performed on material that is of the same P-No and Group No to simulate production welds.
RE: Hardness testing on existing PQR
Thank you for your reply. The request was in the customers specifications. It reads, "As a minimum all PQR's for P1-P6 materials will include hardness readings of the weld deposits in, or converted to, BHN or HVN."
RE: Hardness testing on existing PQR
RE: Hardness testing on existing PQR
RE: Hardness testing on existing PQR
RE: Hardness testing on existing PQR
any new ones we do now i have prepared in both pwht and non-pwht condition, have all the mechanical's done, and then have charpy's done and hardness done.
I have even seen it in specs where the customer wants to send an inspector to witness each welder qualify to the wps.
when I explain that they are already qualified and present the logs, and then tell them how much it will cost to requalify 20 welders on 10 procedures each and that that amount will be billed to his project and will delay things 4-6 weeks..they usually back off that requirement.
RE: Hardness testing on existing PQR
Since the hardness of the weld material is to be tested, I think the issue of having the exact grade of base material becomes less critical, since the deposited weld metal is a brew of both base metal and the filler metal.
Joe Tank
RE: Hardness testing on existing PQR
Most Owners will permit you to weld a coupon using the base metal specifications used in production and perform hardness traverses. I assume the Owner wishes to be in basic compliance with API 582 and has stress corrosion cracking service issues. Ask the Owner for clarification.
RE: Hardness testing on existing PQR
JoeTank: I am waiting for a response from the customer for use of production material. I agree with your statement as well.
stanweld: In the customers spec., there is mention of API 582.
This is my first posting and I did not expect such helpful advice. Thank you all who have replied.
RE: Hardness testing on existing PQR
You're not alone, I've got a job where I have to test all procedures on actual base metal and on the plate with the highest CE.