Modular, Pre-stuffed Pipe Racks

[ConstantEffort]

Anyone care to share advice or lessons learned pertaining to modular, pre-piped pipe racks? Design, fabrication, shipping, installation, or use...

Biggest pain point for me right now is securing piping for shipping and letting it slide for operation. To ship it, the fab shop u-bolts each uninsulated line down tight at every point it passes steel (approx every 10 feet). The skid is shipped out to a paint shop which then coats everything (including any ubolts I spray paint orange for identification and removal in the field). The skid then ships to the site and is set in place, the flanges bolted up, and the plant turned on. After the 1000 foot long run of pipe heats up a bit, say from 70F to 150F, a fair amount expansion needs to be dealt with. If the line is u-bolted up and down its length and then within a few feet of the elbows on either end, I predict we're going to snap a few u-bolts due to shear load.

But the money & schedule people say these lines are 150F (i.e. near-ambient), there is no reason for a pipe stress engineer to look at these lines, and loops wouldn't fit in a modular pipe rack anyway.

Hot (insulated lines) are a bit easier since engineered loops and supports are expected on those already. The field contractor pulls all bolts used to secure pipe shoes to steel for shipping.

 

[pennpiper]

ConstantEffort,
Just a quick piece of advice.
Once you get those Pipe Rack modules to the field and make all the connections you and everyone there needs to stop thinking of them as Modules. The piping will act the same as plane stick build piping.
The pipe will expand in the head of the day and they need to be loose and rith enough spacing to allow for the growth.
Based on some of your comments it sounds like project was not designed by well trained and experienced Pipers.

Get some experienced piping help on site fast.


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

 

[racookpe1978]

1. Document your requirement for removal of the temporary (shipping) u-bolts!

Get that requirement back out to the field, and make sure the project mgr gets it too.

2. Run the pipe stress for those "small" pipes (a straight run of constrained small bore of 1000 feet?) yourself, and get those values to the PM and to your boss.