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Re: [MW:3991] RE: 3981] RE: 3979] Need confirmation as per code

By Materials & Welding
Hi,
 
what will be the approximate length of line?
You need to see that the line is not pressurized, If there are any vent valves on the lines
release pressure and keep them open until welding of support pads/shoes is done.
As Raj said preheating is required.
 
(In the view of hydro testing If there are enough supports on the line regarding
stability of line hydrotesting can be done and support pads/shoes can be welded latter
and no need of any further hydrotesting)
 
I do not think for every fabrication step there will be a code
 
Ohm-Srinivas


ohm guru namasivaya

--- On Thu, 1/7/10, rajagopal kannan <rajagopal.kannan@gmail.com> wrote:

From: rajagopal kannan <rajagopal.kannan@gmail.com>
Subject: Re: [MW:3987] RE: 3981] RE: 3979] Need confirmation as per code
To: materials-welding@googlegroups.com
Date: Thursday, January 7, 2010, 4:04 PM

Hi,
I could understand in this particular case, you need a preheat. Just see, in the factual conditions to maintain the preheat and ensure no sudden cooling. If you can do that, you can go for welding.
Thanks,
K.Rajagopal

2010/1/7 ctcit-an&mma-Dilip Kumar <dilipkumar@ctci.co.th>

Hi,

 

I understand, you mention system is filled by water for hydro test, but hydro test not yet done.

And if Owner is allowing you to perform the welding, you should go ahead; regarding welding point of view, welding is allowable in piping when system is filled,

Even with hydro carbon and under pressure during HOT TAPPING WORK.

 

Sorry I right now I am not in position to find any code for you, for welding applicable, you should contact your QA/QC manager.

 

Thanks

 

With regards.

 

Dilip Kumar ( 帝力普 庫馬 )

P  Note- Please consider the environment before printing this e-mail.

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Hamed
Sent: Thursday, January 07, 2010 3:54 PM
To: materials-welding@googlegroups.com
Subject: [MW:3981] RE: 3979] Need confirmation as per code

 

Hi

I never see in any standard or code to allow in this regard. So I think your Hydro test was rejected . you should release the water & weld the pad & again do the test.

 

Sincerely yours

Hamed Malekan

.Panahsaz Iran Eng. Co.

.Mechanical Expert (LPG Tanks in South Pars-Assaluyeh)

.Tel:  +98 21 88801179  - Fax: +98 21 88900756

 

 

 

 

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of nawab ali bhatti
Sent: Wednesday, January 06, 2010 2:42 PM
To: materials-welding@googlegroups.com
Subject: [MW:3979] Need confirmation as per code

 

 

Dear Members / Friends

 

I need code reference regarding following

                Q.1: Client wants to weld pads without releasing water?

                Q.2:  Can weld without releasing water, if yes what problems will appear  in          future?

                Q.3:  If we can weld, what is the code / standard acceptance criteria?   

                      subcontractor filled water for Hydrotest without completing the welding of some pads(plate 9mm) & shoe supports      

Materials as following

1.       Pipe Thickness is 23.83 mm
2.       Dia 18"
3.       Service : high pressure steam
4.       Design pressure/temperature is 53.4 bar/427C
5.       Test pressure is 148.2 Bar as per B31.3

 

 
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