fabricated pipe

[HgTX]

Does anyone know typical dimensional limits (minimum diameter, maximum thickness) for fabricated pipe?

Hg

p.s. Is there a better term to use than "fabricated pipe"? A web search on that term was a lot less useful than I thought it would be.

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[271828]

Excuse my ignorance. How is "fabricated pipe" different from the standard, extra-strong, etc. pipe in the AISC Manual?

 

[HgTX]

Start with a plate spec (such as ASTM A 709), rather than a pipe spec, then make a pipe out of it. I thought this was done here & there; maybe not?

Hg

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[kelowna]

Maybe it is a different issue altogether, but I have always heard of 'seamless' pipe, that is, extruded as a pipe and therefore no welds or seams and 'seamed' or 'welded' pipe, that is, fabricated from steel plate bent into 'pipe' shape and therefore welded or seamed, either spiral seam or longitudinal seam(s).
Regarding tolerances, I know that they have different tolerances, and I would imagine that they would be indicated on some code. A google search for 'welded pipe tolerances' produced quite a few hits

 

[WmacG]

Try searching for "plate rolling", or "steel plate rolling", etc.

 

[MikeDB]

In the US, pipe is covered by ASTM A53 and hollow structural steel (HSS) is covered by ASTM 500 & 501. The tolerances are different for each standard. The AISC LRFD manual gives a summary of tolerances for each.

For pipe larger than 2", the outside diameter shall not very by more than 1 percent. The minimum wall thickness shall not be more than 12.5 percent less than the nominal thickness.

 

[JStephen]

You'd have to check with a particular fabricator. It would depend on their equipment; also on the quantity needed.

Roughly what size are you needing?

 

[HgTX]

They're looking for 16" OD, 1.5" thickness. That's out of the dimensional range for A 500 & A 501, but I'm not sure why they didn't like the available options within A 53. Instead they were hoping someone would roll A 709 plate to the required configuration.

Hg

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[RWF7437]

As you can see from the responses you've gotten so far "fabricated pipe" is a vague term. Pipe can be, and is, made from many materials including, steel, ductile iron, plastics, wood, concrete, clay, lead, aluminum, hollowed out logs, glass, cardboard soaked in tar, etc. Each has its own specifications, uses and limitations.

Try asking again.

 

[HgTX]

No need to be patronizing; everyone else here understood we were talking about steel.

I think I have what I need, though; if taking standard plate and bending it to form a nonstandard pipe were as standard a practice as my off-forum correspondent seemed to consider it to be, I'd have gotten a different set of responses.

Hg

p.s. Turns out it's worse than I thought--required thickness is 1.75" (45 mm) with 16" OD. Last time I saw anyone try to bend that thickness to that radius, it wasn't pretty.

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[RWF7437]

http://www.manta.com/mb_34_E51F2_000/fabricated_pipe_and_pipe_fittings

 

[HgTX]

Yeah, I found tons of listings of manufacturers. I was hoping more for an indication of what is common practice, but apparently it isn't.

I'm dealing with two parties here--Party A insists on the dimensions, and Party B thought maybe making pipe from plate would be the solution. Neither Party B nor I have yet found a pipe spec meeting those dimensions.

So the current plan is to find out from Party A what solution they had in mind, since they're the ones saying that those dimensions are achievable.

Oh well. Thanks y'all.

Hg

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[hokie66]

I don't like your chances of getting anyone to roll and weld pipe that small with 1.75" plate. Just sounds too difficult.

 

[JStephen]

You might contact Houston Blowpipe in Houston. They have done some very heavy forming to fairly small diameters.

I mentioned the quantity. When you get into something like that, they're going to be forming & welding one can at a time, and if you need a mile of it, it might be a problem. If you just need a few feet or few dozen feet of it, it would work.

 

[flamby]

We do a lot of penstock pipe fabrication out of steel plates for hydroelectric projects. Generally it is done close to the site of installation as transporting pipes is more expensive due to huge volume of hollowness as compared to plates.

Ciao.