Burying black iron pipe

I am laying a black iron pipe in a trench about 3' deep, that is a gas
line for my NG grill. About 10' long.
My question is, would the pipe benefit from anti rust treatment, such
as Cosmoline. Thanks
i
Reply to
Ignoramus11107
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It could benefit from being replaced by a more appropriate material selection, such as the jacketed corrugated stainless gas line that is replacing black pipe for gas service most everywhere now.
Reply to
Pete C.
Why not run galvanized pipe?
Reply to
Mikepier
It will probable last 20-30 years without and treatment, BUT you would be much better off if you wrap it in the self adhesive tape that is available for this application. Usually it is available at a good plumbing supply. Around here, even galv pipe has to be wrapped where it passes through cement. The other way would be to run the proper type of poly tubing for gas service, also available at plumbing supplie stores. Many years ago, I ran gas to my house through black poly. Every time the area flooded, you could trace the path of the line by following the ting bubbles comeing up through the water. Not enough to smell or even be picked up with my gas detector, but the bubbles were there regardless
Reply to
Gerry
Certainly a better idea than black iron. Locally they allow K copper.
Reply to
Toller
Galv pipe is not approved in my area for gas service. The authorities say the zinc will flake off in time on the inside of the pipe and cause plugging of the orifices in gas appliences
Reply to
Gerry
Black pipe is not appropriate for direct burial.
Reply to
George
Get pipe rated for burial.
Black Iron, ain't it.
Cheers Trevor Jones
Reply to
Trevor Jones
OK, what pipe should I use. That's for gas application. thanks
I need the answer ASAP.
i
Reply to
Ignoramus11107
Pete answered your question. In my city, plumbers need special certification to run flex. It isn't even legal for a homeowner to mess with natural gas anyway. Might want to just call in a plumber so you don't cause some disaster sometime down the road.
Reply to
marson
Because some jurisdictions still require black for NG is at least one reason...
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Reply to
dpb
Correction to last...not worded as intended. Some jurisdictions still bar galvanized for NG rather than require black...
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Reply to
dpb
They make black steel pipe with a green plastic corrosion coating, available almost everywhere that carries black pipe.
You have to rust protect all scuffs or breaks in the pipe coating and all joints and couplings with black plastic pipe wrap tape, preferably with two or more coats (one before wrapping and one or two after) of brush on protective coating to seal the tape to the pipe.
Cosmolene won't last underground, it takes a barrier solution.
Make sure to put a shutoff valve before the underground section, so you don't have to turn off the whole house if it leaks. Make sure it's rated for fuel gas, not all plumbing valves are. And put a tee with a "drip leg" in front of the grill shutoff valve, so if there is any condensation in the pipe it doesn't get into your gas grille.
You have to take a special course to buy or use the corrugated stainless "flex line" for gas, but if you want to jump through the hoops to buy it they do make a plastic coated version that can be direct buried. And it will cost a bit more but install a whole lot faster and easier.
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Reply to
Bruce L. Bergman
Here's what happened to an unwrapped galvanized coupling after 3 years of burial in central California......Paul
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Reply to
catguy
I did a similar project years ago, and also used the green coated pipe and wrapped the joints with pipe tape. Now, apparently, my inspectors allow galvanized pipe also, but that wasn't the case then. It apparently can be related to your gas supply - what contaminates are in it that can corrode galvanized pipe.
Your best bet is to talk to your gas plumbing inspector. He knows what is OK for your area, and what he expects. You have to meet his (or her) standards to pass the inspection. I find these people to be very helpful when making these decisions.
Bob
Reply to
Bob F
This brings to mind something I was thinging about to extend the life of the pipe I buried. Would it be advantagous to attach a large buried zinc anode to the gas pipe to delay corrosion when the coatings finally do break down? The wire from the anode could be attached to an above ground portion of the pipe.
Bob
Reply to
Bob F
burial in central
I saw a similar thing happen here in NJ at a condo complex with 120 units. The underground pipe that went from the meter to the individual condo unit was black pipe. We started to see failures within a few years of original installation by the builder. The root cause of the problem was obvious. Upon digging them out, you could see a tar coating had been applied to the top and sides of the pipe, but not the bottom. It had obviously been either brushed or poured on after the pipe was in the trench and they did not do the bottom. The top and sides were OK. The bottom looked like swiss cheese. I would never have believed any iron pipe would fail that quickly. But it did and we had to replace all of them. And just about all of them had either very significant corrosion, or were totally shot and actually leaking gas.
The advice from the local gas company at the time was that black pipe with wrapping was the recommended replacement. Today I would use the new flex gas lines.
Reply to
trader4
check with local codes, I would run the direct burial plastic service line pipe. thats all thats used locally for main service
Reply to
hallerb
If you need the answer ASAP, go to the local plumbing supply place (not Home Cheapo, Lowes, etc) and ask them. Most likely they'll know the local code, or know someone who does.
The Usenet is not the place to ask questions that need answering "right now".
Reply to
Bob M.
The correct pipe for what you are doing is yellow poly pipe. The joints and fittings are melted together. There are stab connections made for this stuff if your AHJ will accept. You may have to hire a plumber to make the terminations.
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CSST is for running on the interior. I do not know if it rated for or accepted as direct bury.
Copper piping is acceptable in most jurisdictions with all joints above ground if possible.
The other choice would be to buy the black pipe with a green plastic coating bonded to it. All nicks, scuffs, dings, and fittings will need special treatment and wrapping with the appropriate coal tar or vinyl tape.
While looking for information to help you, I found this article: Make sure to read detail number 8.
Reply to
DanG

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