SA 516-60 Impact test requirements 3

[gr2vessels]

Our supplier is offering 6" plate with the following impact test: 18 (12) ft-lbf tested at -40 deg C (- 40 deg F). We all know that SA 20 requires 13 (10 )ft-lbf at -46 deg C (-50 deg F).
I don't believe that their offer at -40 deg F is equivalent of the values listed in SA 20 for - 50 deg F.
Would you please advise, am I wrong?

gr2vessels

 

[ijzer]

If you order A 516 60 you have several options:
1. Just order A 516 60 without A20 S5. In that case no impact testing required.
2. Order with S5 and specify the required test temperature yourself .(Could be higher or lower than -46 C)
3 Order S5 without specifying the test temperature , in that case it will be tested at - 46 C or lower.

 

[metengr]

gr2vessels;
I am sorry but I have a hard time following your post with mixed units, and number of impact specimens. What is your plate thickness, 6"? I reviewed SA 20, Table A.15, and the CVN requirements to me are clear regarding testing one specimen or an average of three impact specimens.

 

[SnTMan]

gr2vessels, if 18 is the average it meets UG-84 at your temperature, provided no one specimen is less than 12. Unless your customer requires SA-20 S5, your plate is acceptable.

Regards,

Mike

 

[gr2vessels]

Thank you Gentleman,

I have indeed requested the -50 deg F testing temperature, but I can accept the -40 deg F testing temperature on the basis of table UG 84.4, Note 1. That is, the absorbed energy values tested at -40 deg F are acceptable and in accordance with ASME SA 20, Table A1.15.
Great relief for the project schedule! Thanks again for the help.
Cheers,

gr2vessels