Hardness valve for SA 106, SA 335 P11, SA 335 P22

[Ittichet]

Gentlemen,

I working on the project that require to do hardness test after PWHT but the project spec doesn't give a acceptance criteria.

Where can I get the hardness valve for SA 106, SA 335 P11, SA 335 P22. I checked into ASME Sect II but can not find the hardness value.

Thank you.
Ittichet

 

[metengr]

Since the above are pipe material specifications, use the guidance in Table 333.1.1 from B31.3 for maximum Brinell hardness after PWHT. For carbon steel, SA-106 (P-No 1) in this table, 225 BHN is suitable for a maximum value.I would provide the values but I want you to look them up to verify for yourself.

 

[metengr]

Correction, Table 331.1.1 in ASME B31.3.

 

[Ittichet]

Thanks metengr, In additional. I'm working on Power plant and we use Sect,I and B31.1. Is there anything I can reference.

 

[metengr]

None that I can think of besides the B31.3 is an excellent reference for piping in steam and other process piping systems.

 

[mrfailure]

You also may want to convert those hardness values into approximate tensile strengths per ASTM A370. This would give you a feel that you are meeting the tensile requirements (with the definite caveat that those conversions are considered approximations).

 

[Ittichet]

Thanks for the answers, gentlemen.

 

[weldstan]

Whereas the base material tensile strength requirements are essentially the same, the hardness values overlap and you may not be able to detect differences in the base metal. If it is the HAZ after PWHT, hardness values may still overlap base on time and temperature of PWHT, preheat and interpass temp and thickness. As metengr stated, B31.3 provides info regarding maximum permitted hardness values. From experience, SA-106B HAZ are generally less than 180 BHN; P11 between about 160 to 225BHN; P22 between about 180 to 240 BHN.