ASME section IX PWHT Stainless steel type 410

[LouisLac]

Hi,

If the WPS is qualified with a temperature of 760C can the PWHT be carried out at 595C without re-qualifying the WPS?
Note: there is a toughness requirement in the contract.

 

[DekDee]

LouisLac,
Our continued assistance on this forum is based on members doing everything they can to answer their own questions and when they have exhausted all avenues they come here and we try to assist.
You will not learn anything if you do not try to dig into the codes / standards yourself.
Go to QW 407 - that leads you to QW 407.1 and QW 407.2
There is your answer.

 

[LouisLac]

Hi DekDee,

I have been a welding engineer for a long time and know the ASME code and I have been using this website for many years. My question is to compare my interpretation with other people.

To me QW-407.1(a)(5) means that WPS can be used with a PWHT at 595C

Also, I have read the different interpretations already answered in the committee's interpretation code but all this leaves room for some confusion.

If you do not have interpretation on this point your comment was not necessary.

By the way, I already mentioned that QW-407.2 does not apply.

Thank you for your understanding,

Louis

 

[DekDee]

Louis,
You have a P8 material so QW 407.1 (a) is not applicable

(a) For P‐Numbers 1 through 6 and 9 through 15F materials,
the following postweld heat treatment conditions
apply:

You have a P8 material so QW 407.1 (b) is applicable

(b) For all other materials, the following postweld heat
treatment conditions apply:
(1) no PWHT
(2) PWHT within a specified temperature range

So, a change in temperature is acceptable.

As notch toughness is called for QW 407.2 now comes into play as a Supplementary Essential variable.
However :
This variable does not apply to a WPS qualified
for welding base metals that are assigned to P-No. 8,
P-Nos. 21 through 26, and P-Nos. 41 through 49.

 

[LouisLac]

DekDee,

ASTM A240 type 410 is a p6-gr1 so QW-407.1 (a) is applicable.

So, QW-407.1(a)(5) means that WPS can be used with a PWHT at 595C even if the procedure has been qualified with a PWHT at 760C.

Are you agree?

WPS: P6 gr 1, FCAW, filler metal E410NiMo PWHT: 760

Thanks for your answer

 

[DekDee]

My sincere apologies Louis,
Just saw Stainless Steel and automatically thought P8.
Will take my foot out of my mouth now

 

[DVWE]

Louis, you might be okay in regards to section IX as you have specified in QW-407.1, but you should also consider if ASME Section VIII, Div 1 is applicable. In that case, see Table UHA-32-1 which lists a minimum temperature of 760C, with the exceptions listed in Note (a).

Also consider that your proposed temperature differential is significant, and where impact testing is required, you should attempt to stay within the parameters of the qualification of PWHT, especially noting that the hardness of this material will be affected by a different temperature. That is the purpose of the statements found in Section IX, QW-200.3 and QW-421.1(a)
“The assignments do not imply that base metals may be indiscriminately substituted……”

If I were your customer, I would require the qualification test to closely match the production parameters for those reasons.

The devil is in the details; she also wears prada.