Seamed Pipe - Multiple Seams Allowed?

[msumike]

Does ASME piping code allow welded seam pipe to have multiple seams? Specifically I'm curious about 24" 10s 304-L SS pipe. If multiple seams are allowed, is there a limit? Anyone seem pipe come in with 2 and 3 weld seams? I'm referring to longitudinal seams, not circumfrential.

thanks.

 

[pennpiper]

That is a new one on me!

 

[msumike]

I've been researching this and found in ASTM-A312/A312M "STANDARD SPECIFICATION FOR SEAMLESS, WELDED, AND HEAVILY COLD WORKED AUSTENITIC STAINLESS STEEL PIPES" the following statement:

Welded pipe and HCW pipe of NPS 14 and smaller
shall have a single longitudinal weld. Welded pipe and HCW
pipe of a size larger than NPS 14 shall have a single
longitudinal weld or shall be produced by forming and welding
two longitudinal sections of flat stock when approved by the
purchaser. All weld tests, examinations, inspections, or treatments
shall be performed on each weld seam.

This statement indicates to me that two seams would have been OK, had the manufacturer gained permission to do so. Hmmm... Wonder if someone in procurement gave permission for that.

 

[RossABQ]

Is it stamped with an ASTM #?

I've seen very large AWWA-spec carbon steel pipe made that way, turned out to have been made in Mexico out of used oil storage tank plates. We rejected it.

 

[JStephen]

I think AWWA allows 2 seams on large steel pipe. It may still be limited to "some" pieces of the pipe, not necessarily every joint. The idea is that if you using standard length plates, you con't have to discard the short pieces.

 

[msumike]

I didn't take time earlier to write down what spec, if any, was stamped on the pipe. It was made by Alaskan Copper. Many of the sticks were two-seamed but I did notice one that had 3 seams.

I'll get more info on it tomorrow.

 

[X60]

You may get a concession (depending how flexible your client is) if they used filler material and/or 100% radiography on the welds.