RE: [MW:5576] Re: POAK MRKS ON SAW WELDING

Dear Mr. Rutvik,

Finally I received Lincoln Letter from our welding group regarding the Pock Mark issue. (Photos & Letter attached). Now we qualify the PQR L61 with 860 (flux) combinations. It’s ok. Further we took some precaution at welding stage like proper cleaning of bevel edges and controlled travel speed for the L61+865 combination. Some time it’s ok but not all the time. We cannot explain who’s responsible for this type of defect; ultimately it is the responsibility of vessel manufacturer even though pock marks are not affecting weld integrity.

If anybody having more details please share.

Thanks

M.Masthan

K.S.A

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of rutvik dixit
Sent: Saturday, June 12, 2010 11:01 AM
To: materials-welding@googlegroups.com
Cc: lakshmankumar4@gmail.com
Subject: Re: [MW:5554] Re: POAK MRKS ON SAW WELDING

Dear Mr.Sreevalsan,
Thanks for providing the details. I have faced the same problem. In SAW weld I have observed surface dippression. What is the root cause? Can we take any precaution at welding stage? Who is responsible for this type of defect? flux mfr/ wire mfr./ user? How to avoid it.

I am not sure, this problem may be due to excessive heap of flux on molten weld pool.

can you enlighten us.

With Regards,
Rutvik
Sr.Surveyor
TATA Projects Ltd.

--- On Sat, 12/6/10, sreevalsan sreedharan <sreevalsan68@gmail.com> wrote:

From: sreevalsan sreedharan <sreevalsan68@gmail.com>
Subject: Re: [MW:5548] Re: POAK MRKS ON SAW WELDING
To: materials-welding@googlegroups.com
Cc: lakshmankumar4@gmail.com
Date: Saturday, 12 June, 2010, 10:41 AM

POCK MARKING OR SLAG STICKING

FOR MORE DETAILES PLS CHECK ATTACHMENT

S.SREEVALSAN

ABUDHABI

On 10 June 2010 20:49, lakshman <lakshmankumar4@gmail.com> wrote:

hi,
dear all,

shall i know what is a poak mark,
anybody having the photo of the same.

Thanks & Regards,
Lakshman

On Jun 9, 11:18 pm, "masthan" <sabreenbah...@hotmail.com> wrote:

> Hi
>
> We are continuously facing problem of Poak marks on the SAW Welding surface.
> Welding Consumable L-61 (wire) with 865 (flux) combinations. Any body has
> idea to prevent this. Please share.
>
> Best Regards
>
> M.Masthan
>
> K.S.A

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--
S.Sreevalsan
PB No.2058
QAS,NPCC
AbuDhabi,UAE.
Mob:0504945035/0559862015
Mob.00919995307396 (India)
Email.sreevalsan68@gmail.com
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