Use of Spirally Welded Pipe Sections in Steel Construction 3

[IJR]

Pals

We have once used Spirally Welded Pipe sections in constructing a long span truss. The diameter was 1 metre(40 inch) and thickness around 20mm(3/4 inch). This makes the d/t ratio of 50, not so bad.

Such diameter is rarely found in stock.

We proportioned the pipe section according to some well established German Standard(now DIN EN 2458), a very good standard. But that standard is applicable to pressure vessels too, not essentially a structural code.

So we limited stress ratio to 80%. We stiffened all brace-chord connections.

I am interested if the AISC or any related code has anything against spirally welded pipe sections.

Respects.
IJR

 

[JAE]

Sorry - in the US here I've never heard of spirally welded pipes used in structures....but that's not to say they aren't used here - just in my limited exposure I've never seen them.

 

[IJR]

JAE

I am surprised to the point that I have to guess I havent been able to send my message through with my post.

In Europe, Circular hollow sections are either hot rolled (small diameters), made from hot rolled plates longitudinally welded using high frequency welding techniques(medium diameters up to 355mm, ie about 14") or made from hot rolled plates spirally rolled into pipe shape and welded using submerged arc welding(for larger pipe sections)

What kind of production techniques would be used in US for a pipe diameter of 36"?

respects
IJR

 

[JAE]

IJR - I guess I will have to defer to others on this as I don't deal with that size of pipe...sorry.

 

[dik]

IPSCO produces pipe/tubing up to 80" diameter. Check their web site

http://www.ipsco.com

Dik

 

[WillisV]

Atlas Tube is one of the larger manufacturers of big HSS/Pipe Sections in the US. They use the spiral welding technique that IJR was referring to (see

http://www.atlastube.com/manufacturing_process/index.php#).

AISC doesn't really have any provisions related specifically to spiral welded tubes - they essentially ignore how the tube was made and assume that the final product has the ability to fully develop the plastic strength of the overall section. Therefore the normal guideliness for strength checks of tubular HSS column shapes apply.