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Re: [MW:14534] Tolerance of Rate of heating & cooling

By Materials & Welding

Dear Mr. Parveen K. Nakwal
If construction code is ASME refer Sec. VIII Div. 1 UCS 56

For Heating
Above 800°F (425°C), the rate of heating shall
be not more than 400°F/hr (222°C/ h) divided by the maximum
metal thickness of the shell or head plate in inches,
but in no case more than 400°F/hr (222°C/h).

For cooling
Above 800°F (425°C), cooling shall be done in
a closed furnace or cooling chamber at a rate3 not greater
than 500°F/hr (280°C/h) divided by the maximum metal
thickness of the shell or head plate in inches, but in no
case more than 500°F/hr (280°C/h).

Note : The rates of heating and cooling need not be less than 100°F/hr
(56°C/h). However, in all cases consideration of closed chambers and
complex structures may indicate reduced rates of heating and cooling to
avoid structural damage due to excessive thermal gradients.

With Best Regards

Nagarajan B


Parveen Kumar Nakwal ---13/06/2012 16:49:25---Dear Experts. What is the tolerance limit of Rate of heating and cooling in PWHT process

From: Parveen Kumar Nakwal <pknakwal@gmail.com>
To: materials-welding@googlegroups.com
Date: 13/06/2012 16:49
Subject: [MW:14530] Tolerance of Rate of heating & cooling
Sent by: materials-welding@googlegroups.com




Dear Experts.
 
What is the tolerance limit of Rate of heating and cooling in PWHT process ? Please mention Section & Clause no.
 
Waiting for reply.
 
Parveen K. Nakwal

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