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Re: [MW:8424] HOTTAP on SOUR LINE (PWHT Required)

By Materials & Welding
see here weldment is and HAZ is not coming in contact with process fluid.
 
 two buttweld you can weld with back strip in place,
 
 two fillet weld, as  we weld support where we are not performing any PWHT.
 
regards
 
manoj

On Sun, Nov 28, 2010 at 6:45 PM, Majdi N Elyyan <melyyan@gmail.com> wrote:

Dear All;

 

We have a hot tap on LPG line (Sour service) which require PWHT.

The run Pipe is 4", the branch is also 4", split tee will be used.

As per shell DEP-31.38.60.10 – for Hot tapping, clearly mention:

Hot-tap welding should not normally be performed on materials which require post-weld

heat treatment. However, if stress relieving or post-weld heat treatment is required, a

specialist shall be consulted to assess whether it is feasible to make the specific

hot-tapping operation with post-weld heat treatment.

Note: Stress-relieving may be required if a material is susceptible to stress corrosion cracking and post-weld

heat treatment may be specified by the design code if the wall thickness is greater than a certain limit.

 

& since we have no other options, we have to do the hot tap on the same, kindly advice WPS & PWHT procedures

 

Thank all in advance..

 

Regards

Majdi Elyyan

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Manoj.Vernekar

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