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[MW:2181] Re: GTAW for pipe below 2"

By Materials & Welding
Hi Suhairi,
As the job gets more curved, manipulation for welding (heat input control and access) becomes rather tricky. Root pass is the most critical phase in all welding. GTAW caters to all these serious aspects, hence in case of small dia/small thicknesses, full GTAW is recommended. At the same time, in case of large thicknesses, if you use GTAW for root pass, a sound root can be ensured. On a sound root, good subsequent passes can be easily built up. All that you say, must however, be proven by running a PQR.
Rgds,
S Vagal 
 
 
--- On Mon, 11/5/09, Sukamal Naskar <sukamalbecmet@gmail.com> wrote:

From: Sukamal Naskar <sukamalbecmet@gmail.com>
Subject: [MW:2147] Re: GTAW for pipe below 2"
To: materials-welding@googlegroups.com
Date: Monday, 11 May, 2009, 5:53 PM

Code doesn't guide for the selection of welding process with respect to pipe / tube diameter. It's a common practice, it the dia is <= 2" , we prefer full GTAW.  But for non standard pipes , if the thickness is more, we can go for GTAW & SMAW. I have an experience of such kind of nozzle, 2" dia & thickness 17mm, we used GTAW & SMAW.
The advantage is better control in smaller diameter & less heat input in GTAW process.
 
Regards
Sukamal

On Mon, May 11, 2009 at 7:12 PM, tong tong <tong2je@gmail.com> wrote:
Dear all members,
I need your opinion and advise..it is mandatory to weld piping 2" and below with full GTAW..if yes which spec. or code we refer..Could anyone explain to me the advantage of full GTAW on welding of piping 2" and below..Thank in advance for your cooperation
Regards
Suhairi





--
Sukamal Naskar
Malaysia

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