Limitations of Spiral Weld Joints in Pipes

[mylexicon]

Are there any limitations in using spiral welded pipes for pipelines transporting crude oil(onshore & offshore)? If so according to what code or standard?
I am actually worried about the conditions and stresses arising during installation of offshore pipelines.
I have checked in ASME B31.4, didn't come up with any regulations limiting their use. The only issue was with longitudinal or spiral welded joints with weld joint factors ( E - listed in Table 402.4.3 of B31.4) less than 1.0 not being allowed for offshore applications. This was stated in Chapter IX of ASME B31.4 (Para. A402.4- Allowances ). I haven't checked in API 5L standards yet.
Anyhow, any tips are appreciated.

regards,

drno


drno

 

[BigInch]

No problems with modern spiral welded pipe.

Going the Big Inch!

http://virtualpipeline.spaces.msn.com

 

[mylexicon]

BigInch,
Thanks for the reply.
The only disadvantages that came to my mind regarding Spiral Welded Pipes (hereinafter; SPW) were of practical importance.
I think the only down side with using SPW's are difficulties arising during installation such as:
1- Trying to avoid the weld lines intersecting branch (pipe to pipe) connections while watching for weld ends at the ends of the main spool not aligning with weld ends of adjoining spools.
2- You might have a tough time welding pipe support assemblies to SPW pipes while trying to avoid the helical weld lines on the pipe.
3- SPW method of manufacturing will result in larger percentages of "HAZ" (heat affected zone). Again a problem with welding supports and branches.
Ofcourse, in a pipeline project one won't expect to have branches and pipe supports for miles to come. But on the specific project I am working on, I will need to order for Heat Induction Bending in the offshore section during fabrication of the expansion spool at subsea pipeline tie-in to the PLEM.
Can these pipes be used as mother pipes for Heat Induction bending in the shop? What about Cold bending in the field for onshore pipelines?

many thanks & regards,

drno

 

[BigInch]

Check your code. It may not be allowed to weld pipe supports directly to the pressure pipe, in which case the supports can be welded to a full encirclement sleeve on the pressure pipe.

Same disadvantages as UOE pipe.

I have never done hot bending with SW. Best to check with the bending shop, but I haven't heard of any unusual limitations either. Cold bending within wall thinning and ovalization limit is OK.


Going the Big Inch!

http://virtualpipeline.spaces.msn.com

 

[grampi1]

Sour service is a higher risk for SW

 

[mylexicon]

grampi1,
By saying "Sour service is a higher risk for SW", Do you mean even if we NACE the pipe, SW pipe is still at risk with sour service?

drno

 

[grampi1]

Yes. SW tends to be more susceptible to HIC/SWC. We won't use it in sour service.