ASTM A193 B8 Class 2 Properties

[CSGWB]

Can anyone tell me where I can find elevated temperature properties for ASTM A193 B8 Class 2 Bolting materials (2"). In particular I am looking for Yield and Tensile Information. I have looked at ASME but this material is not listed.

Any assistance would be appreciated.

Regards

CSGWB

 

[metengr]

ASME B&PV Code, Section II, Table 3 lists allowable stress values at elevated service temperature for ASME SA 193 Grade B8, Class 2 bolting material.

The allowable stress values listed in Table 3 are normally used for design applications versus actual UTS or YS.

 

[metengr]

CSGWB;
As a follow-up, I reviewed ASME SA 193. There is a Note in Table 2 of this specification that you need to review and understand. The maximum diameter for B8 material in a Class 2 Grade to assure minimum mechanical properties is 1.5" inclusive. Anything above this diameter will exhibit lower mechanical properties at the core versus the outer surface.

Thus, you will have a hard time finding any specific mechanical property data for this size diameter.

 

[CSGWB]

Metengr,
Thanks for that. I had found the Asme allowables. In this instance I am looking for yield and tensile data to assist in an FEA of a flange assembly at high temperature. Unsure why Part D doesn't list B8 Class2.

Regards

CSGWB

 

[metengr]

CSGWB;
If I had to make an educated case, it is because the Class 2 Grade requires strain hardening to meet minimum mechanical properties. Once you begin to increase service temperature, this will dramatically affect mechanical properties.

I believe this is the reason for the maximum diameter limitation of 1.5" imposed by Section II SC, and ASTM.

Why are you even considering this material in this diameter for an elevated temperature flange? Why not go to B8M material for this application?

 

[CSGWB]

Metengr,

I agree that B8-2 is not ideal, particularly as it is a high pressure (2500#) situation. Unfortunately it is in an existing assembly which is failing in service. We want to determine the failure mechanism in order to rectify the problem.

Regards

CSGWB

 

[metengr]

CSGWB;
I would guess that the failure mechanism is creep deformation.