Underground gas pipe

[Smarty]

Is there a "best" way to install underground gas pipe? Is black pipe preferred to galvanized or vice versa? Should fittings and possibly pipe be covered with some coating like an epoxy paint or silicone caulk or some other coating? Any other hints?

Thanks very much.

[hallerb]

plastic it never rusts or corrodes, its special for gas lines occasionally run in conduit for protection.

if you have a existing gas line thats leaking sometimes a plumber can snake a plastic line thru your old metal line.

metal like steel of any type is a poor choice

[Jimi]

Well since I am in the pipeline welding business and deal a lot with undergound pipe I have to comment... First of all you have to consider legalities of where and what your burying in gas pipe....some places won't allow you to bury gas lines in steel nowadays.....underground threaded connections in steel are also a "no no" in some areas....nowadays they use plastic to bury gas pipe......after looking into that.......This is to answer your question..

If your going to use steel then you should go black pipe ....Galvanized pipe will break down with gas so don't use it (galvanized steel pipe is mainly used with water)....then coat the black pipe with tar and then tape over the tared pipe with plastic tape to seal the pipe from exterior moisture. If you must use fittings underground, It's best after tarring the piss out of the joint, to use heat shrink wrap type sleeves over the tar and fitting for a good seal against moisture.....

Again...for your sake and your neighbours, please go plastic pipe for underground use...The joints should be "fused"....not threaded or Flanged together for underground use...

I just hope I didn't give help to someone that is running an underground grow operation or anything................Jimi

[Jimi]

Smarty,

Since you really have my curiosity , E:mail my business at ............... morriswelding at sasktel dot net ...I'll be glad to answer any questions in this regard....but need to know the application before I can offer advice...especially when dealing with gas... all the best....jimi

[Sacramento Dave]

They make an underground iron pipe for gas Some of it looks like it's wrapped with ten-Mil tape there is deferent types Check with a plumbing supply.( not a big box store) But the best would be plastic gas pipe It comes in rolls and is fused together there are transition pieces for when you go out of the ground, I haven't done any underground gas pipe in long time so I can't remember the names.

[trader4]

All the info Jimi outlines above is consistent with the info I got about 10 years ago from NJ Nat Gas. At the time, I was president of a condo association where we had underground black pipe failing that ran from the meters to the units. This pipe was failing within 6 years of being installed. I would not have believed it could fail that fast if I hadn't seen it with my own eyes. The pipe looked like swiss cheese in spots. If you looked at a length of it, you could see tar on the top, and none on the bottom. They obviously had just poured tar over it while it was in the trench. The untarred bottom was completely shot.

NJNG at that time recommended replacing it with black pipe that was properly tar coated and wrapped. They specifically recommended against glavanized.

My first choice today would be plastic.

[HeyBub]

If you use plastic pipe, some suggest you bury with it some kind of metal - like wire(?) - to make locating the pipe with an electronic gizmo easier. I don't know the particulars - but check out the idea.

[Smarty]

Thanks to all of you who kindly provided answers and info. I definitely check out both the wrapped / covered black pipe and will probably prefer the plastic based on the recommendations offered. My application is to feed a natural gas powered emergency generator which sits a short distance from my home (approx 10 feet) on a concrete slab.

Thanks again. This is an excellent newsgroup!

Smarty