What Class

Date 02-04-2009 19:21 Edited 02-05-2009 15:43

Good question.

I was always taught to use the highest level as the default if none was listed.

D17.1 says the drawing shall list the class.

D1.1 has three "classes," statically loaded, cyclically loaded, and tubular. Most prints that I'm familiar with don't list any of these. The welder must decide. My understanding is that static doesn't move while cyclically is under force.

D1.2 has two "classes," Class I and Class II. Again, most prints that I'm familiar with don't list any of these. The welder must decide.

Keith.

By Milton Gravitt (***)

Date 02-05-2009 00:24

Yes Keith I've have always been told if it's not on the print to weld to class A. D17.1 says it well be on the print, but if it's not if you use Class A in Table 6.1 acceptance criteria I would think you will be right or maybe that's what a customer would like to hear.
Thanks Keith

By 803056

Date 02-06-2009 03:45 Edited 02-07-2009 04:27

All though I hold welders in high regard, the decision to meet Class A, B, or C in the case of D17.1 or the requirements for static nontubular or cyclic nontubular/tubular for D1.1 is not the welder's to make. The welder has no idea of what loading conditions have to be met.

If there is any question, the customer (or design authority) should be consulted. If no response is forthcoming, bid the job to the most critical requirements and meet those more stringent requirements to be safe. The acceptance criteria is different for the different weld classes and the NDT may be different as well. Better to be prepared than to get caught with your pants down.

Best regards - Al

By Milton Gravitt (***)

Date 02-06-2009 15:44

AMEN Al