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[MW:576] Re: Heat treatment of a jacketed vessel

By Materials & Welding
Also, in order to reduce / eliminate thermal stresses - control the rate of heating and cooling. The maximum temperature between the thickest and thinnest parts undergoing PWHT should be kept to within 50C
 
regards,
 
Jayesh




From: pshrikant@mis.ae
To: materials-welding@googlegroups.com
Subject: [MW:569] Re: Heat treatment of a jacketed vessel
Date: Wed, 13 Feb 2008 07:51:53 +0500

It will be better if the vessel is supported on vessel supports (integral vessel supports) during PWHT.
 
At PWHT temperature, if the vessel is supported on other temporary supports (on jacket), the jacket may buckle in due to heavy vessel weight.
 
Thanks,
 
Shrikant
 
----- Original Message -----
Sent: Tuesday, February 12, 2008 16:30
Subject: [MW:568] Re: Heat treatment of a jacketed vessel

During PWHT keep open inlet and out let of jackets. Ensure that air pressure inside jacket is atmospheric.
As you mentioned shell thickness 80mm and jacket with 12/14mm.
Take care and support the equipment properly.

On Jan 31, 2008 9:37 PM, Bathula Raghuram (Mumbai - PIPING) <R.Bathula@ticb.com> wrote:
In a worst case scenario what will happen when a large vessel with jacket subjected to PWHT? (core thickness of up to 80mm and jacket thickness of 12/14mm, both are made of SA516)
 
What are the precautionary measures?  Please share your views interms of distortion, bulging, vaccum, entrapment etc.
 
<BR

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