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RE: [MW:12230] Gas purging for 12Cr1MoVG

By Materials & Welding

Dear Endri,

 

Taken from API 582

7.3  Back purging is required for the GTAW and GMAW

processes for welding materials having a nominal chromium

content greater than 2 1/4% unless the joint is ground or back

gouged to sound metal.

 

I am agree with sri lakshmi. The main reason using Back Purge is prevents oxidation. But in Golden Joint case you can’t do back purge.

If your PQR accept with no Back Purge, and your Welder is high skill than go a head… But if your PQR stated a back Purge and your skill welder is intermediate,

It’s recommended use back purge.

 

Regards,

Firman Bhaktiwinaya

 

 

 

-----Original Message-----
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Raghuram Bathula
Sent: Tuesday, August 16, 2011 10:59 AM
To: materials-welding@googlegroups.com
Subject: Re: [MW:12227] Gas purging for 12Cr1MoVG

 

refer para 7.3 of API RP 582

 

On Sun, Aug 14, 2011 at 7:20 PM, Endri Prasetyo

<endri.prasetyo@gmail.com> wrote:

> Dear Mr. Raghuram,

> Can you please share here in which statement of API 582 that mentions about

> it?

> Thanks and regards,

> Endri

> 

> On Sun, Aug 14, 2011 at 2:55 PM, Raghuram Bathula

> <raghurambathula@gmail.com> wrote:

>> 

>> i guess the %Cr <2.25 in this material, in that case back purging is

>> not required as long you have a qualified PQR without purging.

>> Generally purging is recommended for materials with Cr >2.25% (refer

>> API 582).

 

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