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[MW:9423] RE: 9420] NDT after Weld

By Materials & Welding
Hi Larry,
 
The subject material is a low temperature carbon steel.(Typically P1 Gr1). For such materials unless special requirements are warranted by client, B-31.3 ( I'm referring to -2008 edition) code does not have any time restriction/ delay requirements for performing RT on completion of welding.See the attached code interpretations on RT requirements for various materials.
 
In fact RT may be performed for 300NB x 34mm WT LTCS A333 Pipe, following completion of welding, before  PWHT. If there are concerns of any delayed cracking (which generally should not happen for such steel), the recommended practice would be to use H4 grade of SAMW consumable consistently for welding.
 
Thanks.

 

Pradip Goswami,P.Eng.IWE
Welding & Metallurgical Specialist & Consultant
Ontario, Canada.
Email-pgoswami@sympatico.ca,
 
 

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Larry
Sent: Sunday, January 23, 2011 8:16 PM
To: materials-welding@googlegroups.com
Subject: [MW:9420] NDT after Weld

Hi there,

 

 

Welding Code: ASME IX

 

Construction Code: ASME B31.3

 

Material: 300NB x 34mm WT LTCS A333 Pipe

 

Question: How many hours after welding, that you are allowed to do radiograph test. Do you have to wait certain hours? Is there a minimum hours as per code?

 

 

 

Many Thanks,

 

Larry Zarate

 

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