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[MW:25367] RE: 25366] Re: Requirements Of PWHT for the Cross Country Pipe Lines - Reg

By Materials & Welding

There is no mandatory PWHT requirement in the codes for this diameter and wall thickness but since it is a sour service pipeline you will need to apply a mandatory maximum hardness for all areas of the weld, heat affected zone and parent metal of 248 HV10. Your contractor will have to achieve this in their welding procedure tests and in production. In theory if they fail to achieve it then PWHT can be applied (subject to doing this in a new welding procedure qualification) but it would be more practicable to revise the preheat levels and run a new procedure.

 

 

Alan Denney

AKD Materials Consulting Ltd

 

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of zhy370137@gmail.com
Sent: 11 September 2016 07:55
To: Materials & Welding <materials-welding@googlegroups.com>
Subject: [MW:25366] Re: Requirements Of PWHT for the Cross Country Pipe Lines - Reg

 

 

Dear raj:

    

    would you mind giving me a explanation about  whether PWHT is applied for following pipeline

    sour condensate pipeline  

    diameter : 20 inch  thickness: 10mm  length :164km

 

 

 

 

 

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