Vertical Expansion Loops

[MickMc]

Hi,

On a recent site visit in (Middle East)for future project I noticed that the interconnecting pipelines between various plants and/or loading terminals are run on as expected pipe tracks/sleepers but the expansion loops are in a vertical plane with vents rather than the traditional horizontal. The routing of these lines are in nominated pipe corridors of various kilometres of distance and my assumption is that the vertical approach is to reserve future space and maybe even be an aspect of trapping inventory between loops in event of leak.

Can anyone clarify as most of my experience is inside battery limit.

Regards.

Mick.

 

[pennpiper]

This was done on a job in a middle East country on a long sleeper pipe rack and the vertical loops served two purposes. First, to adsorb expansion and second, to jump over road crossings.

Sometimes its possible to do all the right things and still get bad results

 

[BigInch]

Horizontal is not "traditional". Vertical loops, or vertical and horizontal, are used in almost every refinery I've ever seen.
They are probably not so concerned with trapping inventory, as they are as providing future expansion capability. Most Mideast units are large now and going to get larger in the future.

And yes, always at road crossings. You kind of get an expansion loop even if you didn't want one.

 

[Gator]

Since OP's experience is mostly IBL, he's no doubt thinking about the nested (or single) expansion loops as seen on piperacks as "traditional".

Piping Design Central

 

[MickMc]

Guys thanks for the feedback.

Gator is correct in that my experience is with nested expansion loops on racks and sleepers within and connecting plant areas/units and storage facilities with and additional 15%-20% added for future lines. This particular operator has a mix of LNG/GTL/Refinery related products in overall site with plot space reserved for future plants and corridors of various width for product/utilities/power crisscrossing the entire site.

The vertical expansion loops are solely to adsorb the expansion as roads crossings are usually underground box culvert and pipe bridges used at intersecting corridors where I expect they will be factored into expansion. I have had further information that the vertical approach is solely related to space constraints and inventory not considered in case of leak. I am also told that pockets are not an issue as product is in finished state, normally flowing and can be dewatered or emptied by soft pig.

Any lessons learned during design/commissioning/operations would be welcome as FEED stage is imminent and better to address there.

Regards.

Mick.