Is a PQR with A 312 TP 304/304L (Dual) covers WPS with A 312 TP 304?

[nacer16]

Construction code : ASME B31.3
Qualification code: ASME IX

I have a PQR qualified with A 312 TP 304/304L (Dual) (Non-assigned in ASME IX Para. QW-422)
Can use it to weld a A 312 TP 304 (assigned in ASME IX Para. QW-422).

If not. What I can do in this case?

Thank You for your replay !

 

[weldtek]

nacer 16,
Both materials are listed so you may consider it 'assigned'. A dual certified material simply means it meets both specifications.
The only possible objection I could imagine someone having is if the specimens failed in the weld at < 75 ksi. An unlikely scenario.

 

[nacer16]

weldtek,

Thank you for your quick answer.

But the question is whether according to provisions of ASME IX can I use a WPS to weld a 312 TP 304 which is assigned as P 8.1 according to Para. QW 422 in using a PQR established for a 312 TP 304/304 L (non assigned).

Otherwise, on ASME IX Para. QW-424.1 we can read "metals that do not appear in table QW/QB-422 are considered to be unassigned metals except as otherwise defined for base metals having the same UNS numbers"

Can I understand that if 312 TP 304/304L has the same UNS number like 312 TP 304, we can use indifferently his PQR to weld 312 TP 304 ?

Regards

 

[weldtek]

What makes you think the dual certified material is unassigned?

 

[Duwe6]

Not only is dual-certified 'assigned', but the ones you mention have the same "P-number".

If the above statement doesn't make sense to you, then you need to (re)read Chapter 4 of ASME Section IX. WPS's [usually] cover entire P-numbers's.

 

[nacer16]

To weldtek and Duwe6

Thank you for your quick answers.

I have no doubt on the explanation you give. Otherwise, I will not ask on this forum.
It's true that I must (re) read Chapter 4 of ASME IX.
Because, in my understanding and in accordance with paragraph QW.422. the 312 TP 304 is classified as P8.1 and also A 312 TP 304L is classified as P8.1.
And the two are classified separately.
I thought that the dual must be also classified separately.
And I think that's here that there was a confusion on my part.

Please be indulgent with my english because it isn't my native language and I must make some efforts to write in English.

Regards

 

[Duwe6]

Keep in mind that the P# subgroup is ignored unless "Suplemental Essential Variables" are needed -- typically for Impact Toughness outside the 'normal' temperature range for the material. Since P8 materials are OK down to about -325°F, I have never seen this happen.

Thus, one P8 is equal to another P8. The supplemental number - the .1 of P8.1, does not apply. So all P8's are considered equivalent for the purposed of ASME Sect IX.

And your written english is quite adequate. There is room for improvement, sure, but you have been fully intelligable, sir.