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[MW:14442] RE: 14426] Tank Clean out door PWHT

By Materials & Welding
Dear Mr.Thomas.,
Re a/m subject. Regarding the PWHT:
1. it is either based on the standard you are using as API 650 general
requirement as in relation to thickness and material type and grad or as
special conditions : internal material is lethal or the subject ligament
will be under sever stresses regardless of thickness. Which also affect
the intensity of RT.
2. Yes you can do localize PWHT but you need a specialized capable team
and equipments most preferable in my opinion using gas heaters with
recordable chart readers.

Best rgrds
D.eng.A.Aziz Gendia
ecco-spi President & CEO
Mob.: +2012 21 33 956
Fax: +202 2477 8411
e-mail: ecco-spi@gmail.com

-----Original Message-----
From: materials-welding@googlegroups.com
[mailto:materials-welding@googlegroups.com] On Behalf Of thocho37
Sent: Thursday, May 31, 2012 7:19 AM
To: Materials & Welding
Subject: [MW:14426] Tank Clean out door PWHT

Hi, Can any one tell whether I can carry out PWHT of clean out door welding
after erection of first shell course?
We have erected the clean out door section of the shell plate and completed
vertical welding without performing the PWHT. As per API 650, it needs to be
completed PWHT regardless of thickness before assembly(erection).
if that is the case, I have to cut the joint and do the PWHT and reweld
again.Can I do PWHT at site after erection?
If not, any one explain me what is the reason behind it. Why API is
insisting to have PWHT before erection.
Cheers,
Thomas

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