ASTM/ASME SA-193 P-Number ????

[Vdubb98]

I'm writing a weld procedure to tack a Nut (SA-193 gr. B7) to a valve indicator body. I have the P-number for the valve body but there is no p-number listed for SA-193 gr. B7. Can I do an equivalency for SA-193 based on chemical composition and if so what is the criteria? Thank you very much for any assistance you can provide!

Jake, E.I.T.

 

[stanweld]

There is no P-No. for the A-193 B7 bolt and you cannot equate a P No. to it. Also the B7 material may include a number of AISI low alloy steels such as AISI 4140. Please note that A-193 is a bolting specification - not a nut specification.

 

[SnTMan]

Vdubb98, when welding -B7 studs to -2H nuts for low risk situations, such as making a jackbolt or something, I instruct the shop to "weld it like it's a low-chrome". They generally NDE the completed weld.

BTW, we had a fairly serious injury sometime back because the shop had taken it upon itself to weld two -B7 studs together end-to-end to make a longer one for drawing some parts together or something like that. It let go when no-one was ready. Welding studs together is not permitted these days.

Regards,

Mike

 

[metengr]

Vdubb98;
I would recommend an ASTM A 194 2H carbon steel nut (P-No 1) to tack weld on the valve indicator body, versus a low alloy grade nut. If you decide to use a stud instead of a nut, go with a carbon steel grade stud versus Grade B7.

 

[Vdubb98]

Thank you all very much for your excellent replies. Your input was very helpful!!

Jake