PWHT and Welding Procedures

[lalaith]

According to B31.1 (para. 132) you do not have to PWHT P5A (2.25 Chrome) material if it is 4" in diameter or less, 1/2" thick or less and has .15% carbon or less.

We are having a debate as to whether this exemption allows you to weld the material with a procedure that has been qualified with PWHT, or do you have to have a procedure qualified without PWHT.

I believe that since PWHT is an essential variable you will have to have a procedure that has been qualified without PWHT.

I would appreciate knowing how everyone here interprets this section of the code.

Thank you,
Lalaith

 

[welding1]

The following clause in ASME 9 is essential for all welding processes.

QW 407.1
A separate procedure qualification is required for each of the following conditions.
(a) For P-No. 1, P-No. 3, P-No. 4, P-No. 5, P-No. 6, P-No. 9, P-No. 10, and P-No. 11 materials, the following postweld heat treatment conditions apply:

(1) No PWHT;
(2) PWHT below the lower transformation temperature;
(3) PWHT above the upper transformation temperature (e.g., normalizing);
(4) PWHT above the upper transformation temperature followed by heat treatment below the lower transformation temperature (e.g., normalizing or quenching followed by tempering);
(5) PWHT between the upper and lower transformation temperatures.

(b) For all other materials, the following postweld heat treatment conditions apply:
(1) No PWHT;
(2) PWHT within a specified temperature range.[A99]

Hope this answers your question. For more information on ASME 9 and other welding topics

http://www.gowelding.com

 

does ASME B31.1 require radiograph inspection of every weld or does it require some percentage radiograph inspection? I believe it is 100% inspection but am not sure, can someone verify and quote the appropriate section to me, thanks