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[MW:13493] RE: 13484] Pre-heating for cutting

By Materials & Welding

Dear All,

 Beyond all the technical aspects, small logic for this situation….

This is only my view…

 

After cutting the edges are again welding to some part / connection(say pipe, fitting, flange, etc or leaving like that) in all the cases if welding is going to do it will be again preheat and PWHT after welding so any thermal shocks will be relived during PH, PWHT,

 

So I think no need of pre heating.

 

Thanks and Regards................?

 

Lakshman Kumar.B|Manager |Lanco Infratech Limited

Plot No 1255 | Sanjeevani chowk | Mahanadi vihar | Cuttack 753004

Phone : + 91 671 2445033 | Mobile : +91 9937286851 |www.lancogroup.com

Go Green|The future will thank you

 

 

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of jesti fer
Sent: Monday, January 16, 2012 3:22 PM
To: materials-welding@googlegroups.com
Subject: [MW:13484] Pre-heating for cutting

 

Dear Experts,

 

I need your help for this subject, We are fabricating some piping as per B31.3, the material ASTM A106 Gr.B, 8”Sch-XXS and 160 and we are doing preheat and PWHT for welding, but my enquiry pre heat is required for cutting also? It is mentioned in any code or any other were? Please help me

 

Jesti

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