station piping 1

[millimeters]

Hi,
I am looking for some information regarding the pipe fabrication methods. Is there any preference regarding SMLS (Seamless) v ERW (Electric Resistance Welded) v DSAW (Double Submerged Arc Welded) for station piping with MAOP of 650 to 900 psi?
Cheers

 

[BigInch]

Not really. Cost is the typical deciding factor.

I hate Windowz 8!!!!

 

[millimeters]

Thanks

 

[Duwe6]

Just make d@mn sure that nobody uses Type F piping. Properly refered to as 'furnace welded', but most of us old guys call it Furnace Brazed for a reason.

Under A53, all E [ERW] seams get 100% 'electric' tested [typically eddy-current] at 2" and up. I've never had a problem with type E, just F.

 

[SectionIX]

Some corporate specifications require longseams to be at certain locations (e.g. 10:00 to 2:00, not at 12:00, staggered by 50mm, etc). In this case, seamless would be advantageous.

 

[LittleInch]

Generally speaking, most construction specifications don't allow seamed pipe to be cut or welded on the weld seam. This might be easy if there is only one weldolet or nozzle, but if there are many on one piece of pipe it can become difficult to accommodate this requirement.

Seamless is difficult to get above a certain size range (12 to 16" from memory) so there is little choice above that but below I think you would find seamless generally preferred for piping as pipe is relatively cheap compared to flanges and other fittings and seamless just makes this sort of thing go away.

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Also: There's usually a good reason why everyone does it that way