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Re: [MW:31004] NACE SP0472 edition 2010 - ROAD MAP SP0472 TABLE 1

By Materials & Welding
Hi,
Control of base metal composition (CE) to control hardness of the HAZ may not be enough because HAZ hardness is controlled not only by composition alone but also the cooling rate and subsequent heat treatment to prevent formation of hard microstructure.
Therefore composition control and thermal control are necessary. 

On Sunday, 14 June 2020, 17:09:36 GMT+1, Vishwas Keskar Welding Manager WELDING <vvkeskar123@gmail.com> wrote:


We have Pipe Line for Wet H2S service . PWHT is addressed in drawing by designer .

There are 3' to 96 " pipe lines  with thk @4mm to 15 mm , made up of  P NO 1 GR 1 - SA 106  Gr B material.

We intend to  follow road map and avoid PWHT  as below
1. Weld deposit - Weld deposit with  ASME  A-NO. 1 chemistry  - maximum HARDNESS  248HV10 
2.CE of base material Control Method (CE of production base metal  shall not  exceed  CE of PQR specimen by 0.03 %   and HAZ hardness check - maximum   HARDNESS 248HV10

Is it intent of STANDARD Edition 2010 that HAZ Hardness Control (maximum HARDNESS  248HV10 ) shall be 
by CE of base material Control (as stated above)  AND  One or more Thermal Methods .
 Solely CE of base material Control  is not sufficient .
 Can  the thermal Method  be  waived ?

Pl. guide further 
 

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