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Re: [MW:11574] Hardness Requirment

By Materials & Welding
for sour service max limit for acceptance is 22 HRC, hardness check requirement and NACE std applicability depends on severity level and type of service,  to be defined by process designer.

Yes, PWHT is recommended to reduce the hardness, but one need to investigate before taking a decision, normally for CS it won't exceed 22HRC.

On Sat, Jul 2, 2011 at 3:25 PM, SENTHILKUMAR SWAMINATHAN <skumarswami@yahoo.co.in> wrote:
Hi All,
 
I am having a doubt on the hardness test required or not for the follwing:
 
Construction Code: B31.3
Matl Specn: SA106 Gr.B
Dia 4 - 12"
Sch: 40 & 80
Type of service: Sour
 
1) Is it required to refer NACE MR-00175 as well.
2) If hardness value goes high, then go for Heat treatment?
Pls. give your feed back. 
 
Regards,
S.SENTHILKUMAR


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