[MW:578] Re: Heat treatment of a jacketed vessel

I think, it is not advisable at all, to carry out the PWHT of the vessel
with such Shell/Jacket thickness.

1) The jacket thk of 12-14 mm may not require PWHT as per code. Try if you
can avoid.
2) In case, it is not avoidable, go for separate PWHT of Shell/Jacket
followed by local PWHT of the closing joints. This will help avoid the
complications.

Best regards,

Prasad Joshi
e-mail: pjoshi@technip.com
Phone: +971-(0)2-611-6643

Jayesh Dave
<j_j_dave@hotmail
.com> To
Sent by: <materials-welding@googlegroups.com
materials-welding >
@googlegroups.com cc

Subject
17/02/08 09:54 PM [MW:576] Re: Heat treatment of a
jacketed vessel

Please respond to
materials-welding
@googlegroups.com

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 -----
From: Nilesh Pathare
To: materials-welding@googlegroups.com
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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