Piping Material for Fire Protection Underground Piping For Power Stations

Just about $200.00USD/hour consultation fee will get you an answer.

Google's faster and cheaper.

Go there and ask the question.

"Plastic" underground pipe is okay (when rated) within 100 feet of equipment.

Always approach equipment with steel pipe.

If a transformer blows to a burn, how do you think plastic pipe wili hold up?

I have first hand experience here.

If a pipe is underground, then it is not surrounded by air containing oxygen. So just how it is supposed to burn just there, and why is it supposed to need protection therefrom?

Heat can penetrate the ground and melt or soften the pipe. It does not have to "burn" to be a major problem.

While may be true that once buried a virgin underground pipeline (only that pipeline, contents and the ground involved) may thereafter not be exposed to extreme temperature conditions, it is also true that in the real world of increasing utility etc. congestion many non-metallic pipes and conduits have failed over the years, and even in underground applications, when they are exposed to e.g. heat. An example is reflected in Case 3 on page A-8 of the site at http://www.wbdg.org/ccb/ARMYCOE/PWTB/pwtb_420_49_6.pdf .

Hi Anon.,

In the past 30 years I have been involved in new installs and O&M on fire systems in Major projects in 5 continents and 30 different contracts.

The range of materials have been

1) Coated steel, strong but will corrode fairly rapidly, and leak depending on soil electrolysis and induced currents from electrical equipment.

2) Cement coated, mechanical joint /bell and spigot ductile iron, The most expensive but hands down the best, most reliable. Ie. An installation on a GE frame 9E power plant project in Central Asia about 1 km pipe 20 hydrants full loop with full isolation --Only 1 seep in testing, which took a few more turns of a wrench on the bolts.

40 year old sections I dug up during O&M work still as good as new.

Annon. part 2

3) class 160 pvc OK but even with mechanical joints can, and will, creep and leak--- especially after flushing operations or any differential settling. I have had pipe bursts during testing at NFPA recommended pressures.

4) HDPE is the second best, after Cement coated ductile iron (and is also the easiest) --You must be sure to use extra heavy duty and the proper transition fittings. per NFPA and experience, the final connection to the hydrant should be ductile. from isolation valve--- 2 or 3 meters . This provides stability against thrusts.

5) Fiberglass don't even think about it! it doesn't meet NFPA and it is no good underground-- differential settling at all and it breaks the joints.

Good luck

Expat 07

Better go for composite pipe, which is HDPE inner layer, Aluminium second layer, HDPE final layer. If you need help in sourcing then I can help you with mfr. from India with Swiss collabrarion.

Go head with E - fiberglass extured tube, which will readly available and good fire protection, corrsion resistance with stand good stifness load and major is light weigth.

HDPE for UG - Carbon Steel AG- wall thickness dependant upon your pressure(s)