Hardness value for A106 gr. B 1

[replica]

Dear all,

I have done hardness measurement on the 6" pipe of A106 Gr. B material and found that the average values are between 130 HB and 218 HB. I know that the hardness value is not specified in ASTM A106 Gr. B and only the minimum UTS of min. 415MPa was specified. Can I use this UTS of 415 MPa which is about 123 HB (base on ASTM A370) to estimate the minimum hardness value? If so than my 218 HB is acceptable because it is above the minimum of 123HB. Is the any maximum hardness value for A106 Gr. B? Where can I get the information?

Any comment is highly appreciated.

Regards,

 

[metengr]

Typically, for A106 supplied per the material specification the bulk hardness will be below 220 HB based on past expierence. There is no formal maximum hardness requirement that I know of other than the hardness to UTS conversion you mentioned.

 

[replica]

metengr

Thank you very much....as usual really appreciate you prompt reply and good to know that you are still posting....keep it up.

 

[metengr]

Replica;
Also, keep in mind that material specifications under ASTM/ASME typically use minimum specified strength values because that is all that is necessary under design by rule. In other words, you don't receive credit for materials having higher strength values above minimum, for design. Which is why there is no maximum hardness for materials unless specified for specific service applications.

 

[replica]

Thank you very much metengr. Noted. So is the higher strength ie higher hardness for this material acceptable and only limited to application if any? Happy new year and have a nice weekend.

 

[metengr]

Yes it would be acceptable provided it meets the other requirements in the material specification.