Stainless steel fittings and standards: help required! 1

[mikeg8]

Hello All!

I'm really struggling to come to terms with various ASTM standards which I'm sure you all know about...

Example: I'm specifying stainless steel (304 type) butt-weld fittings. The geometric standard for these is ASME B16.9 (I hope, or I've got EVERYTHING wrong!). The material standards I've listed as ASTM A312 and ASTM A240 (depending upon whether the item was fashioned from pipe or plate) and the forming designation as ASTM A403. Schedule of the fitting to suit the pipe size. Is any of that correct or have I got hold of the wrong end of the stick?

Many thanks if you can help

Mike

90% of a project takes 90% of the time...the last 10% of a project takes the other 90% of the time!

 

[Cockroach]

The butt end weld profile depends on wall thickness and the ratio of material strength between the pipeline/pressure vessel to component intended fo weld. A good example of this is in the appendix of CSA Z245.15, a forged steel valve standard in Canada.

I believe that ASME B16.9 is exactly that standard, CSA Z245.15 for butt end weld, my memory is old and would need to be looked up to be sure. I am confident it is though. So I think you are on the right track, taking into account the difference in material strength and wall thickness.

Hopes this helps.

Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada

 

[ytse]

Generally stainless steel fittings are to the following standards:

Wrought (buttweld) fittings: ASTM A403 material to ASME B16.9 dimensions.
Forged (socketweld or threaded) fittings: ASTM A182 material to ASME B16.11 dimensions.

Actually, B16.9 & B16.11 covered more than just dimensions, it also covered pressure ratings, marking, testing, etc. You do not need to list A312 (pipe) or A240 (plate).

 

[mikeg8]

Cockroach, Ytse: thanks fellas. I think I can see my way out of the forest now!

Mike

90% of a project takes 90% of the time...the last 10% of a project takes the other 90% of the time!