RE: [MW:23595] Regarding RT before or after PWHT

Hey Guys ;

B31.1 and 31.3 have to do NDT after PWHT with P no. 3, 4 ,5A , 5B

It is quite common in some situations to perform a preliminary NDT, so to speak to establish the basic soundness of the weld especially on large bore or heavy thickness weldments but this would always be followed by an equally stringent NDT after any PWHT. 

RT or any other NDT does not alleviate the need for 'P'WHT as even a weld with no indications can develop delayed stress cracks .

For a joint and material so designated, it is smart to perform preliminary NDT before post weld heat treatment to assure you don't already have something that will require repair welding and further PWHT.

But I have never heard of a client accepting anything other than a post(!) PWHT NDT report, to do so would be an ultimate folly, as any amount of defects could arise due to the thermal stresses involved in PWHT.

Best Regards 

Elias 

---

Date: Tue, 29 Sep 2015 13:04:04 +0530
Subject: Re: [MW:23585] Regarding RT before or after PWHT
From:.@gmail.com
To: materials-welding@googlegroups.com

For alloy steel greater than 3Cr, RTAfter PWHT.??

On 29-Sep-2015 10:07 am, "Ajay" <donsaab3@gmail.com> wrote:

Dear Sir,

As we all aware that PWHT and RT both are different in nature, in general we perform RT after PWHT(Where PWHT is required to be perform after welding). 

However it is not written anywhere that RT is to be performed after PWHT only.

My question now is , can we perform RT first and then go for PWHT? will it be acceptable ????.

I have seen many client inspectors asked contractors to perform PWHT first then RT whereas their specifications does not say anything in this regard.

All experts are requested to throw light on the subject. Documented proof/literature , if any, to support this will be higly appreciable.

regards,

Ajay 

--
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To post to this group, send email to materials-welding@googlegroups.com.
Visit this group at http://groups.google.com/group/materials-welding.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAM6T1-EGdHb%3DKoxGb-OuLZr5Dr8KpP7_dLG72WQ6AaUdJ-XG-w%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.

--
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To post to this group, send email to materials-welding@googlegroups.com.
Visit this group at http://groups.google.com/group/materials-welding.
To view this discussion on the web visit https://groups.google.com/d/msgid/materials-welding/CAJzm4eM5D7bZpXebwXZ0fzw4xPKfHr6XrZFgQ8RKMuAq8Cd_NA%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.