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[MW:12374] RE: 12370] Hardness in Tube to tube sheet welding

By Materials & Welding

Hello Inamdar,

T-TS qualification is well covered by ASME Sec-IX, 2007 edition onwards.Hardness requirement is more of process/service media driven requirement.Hardness limits are  not covered in Sec-IX nor any of the design and fabrication codes ,such as ASME Sec-VIII,DIV-1 or DIV-2, though all the above codes mentions that hardness readings are to be taken, if required.

What's the design code ?
Are  there any additional specification requirements such as NACE MR-0103, MR-0175 or any of the API recommended practices?
Is there any client's specification involved?
 
If you could specify the details , it would help to provide precise answer.
 
Thanks.



Pradip Goswami,P.Eng.IWE
Welding & Metallurgical Specialist & Consultant
Ontario,Canada.
Email-pgoswami@sympatico.ca,
pgoswami@quickclic.net

-----Original Message-----
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Inamdar
Sent: Thursday, September 08, 2011 1:05 AM
To: Materials & Welding
Subject: [MW:12370] Hardness in Tube to tube sheet welding

I seek some guidance in the above.
Our Hardness for tube to tube sheet welding is coming above 250HV and the desired value is 210 Avg.
Can some body explain me the below:
1) Which code clealy specifies the maximum acceptable value of hardness in TTS welding.?
2) How to control the hardness without PWHT in TTS welding?

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