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What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 3:42 pm
by Diemjoe
Hi,
I am planning to store my 20# propane canister on the trailer tongue and run a black pipe to the galley. I will weld it to the cross members. I will probably have a y connector so that I can use my camp chef stove externally to the trailer while still using a built in propane cook top. Will a 1/2" pipe meet the pressure requirements? Other ideas are welcome.

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 4:45 pm
by goldcoop
Don-

Not sure I would weld the pipe to the frame for fear of weld causing leaks. Better to clamp it. Better yet to use 3/8 soft copper with flare fittings.

Cheers,

Coop

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 5:19 pm
by Diemjoe
Probably should have clarified, Would weld the clamps not the pipe. This will be running under the trailer wouldn't soft copper be more susceptible to nicks and dings from road debris?

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 5:40 pm
by lrrowe
My plans for exterior propane piping will be black pipe of the standard size normally used in household construction. It will run underneath the frame and held in place by some sort of clamping device. I am using this kind of piping so nothing from the road or ground would nick the line. Of course, while traveling, the valve at the tank will be shut off. Interior pipe runs could either be copper or the shielded type, again like is used in the house. I will make the final decision after I see what the layout actually looks like.

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 5:55 pm
by Diemjoe
The Black Pipe I see at Lowes is usually 1/2 or 3/4 . 3/4 seems pretty big to just the fire up the camp chef and the built in gas top. I don't think the flexible tube I connect with now is more than a 1/2. But is buried in the garage for the winter so I am not sure. There will probably be 10'ft of run from the canister to the end of the black pipe. Plus maybe 8 feet of flex cable from there.

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 5:56 pm
by lrrowe
I think I agree with you on the 3/4'.
I guess I just need to check out Lowes and then evaluate things then.
I am just trying you options to think about.

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 6:01 pm
by MtnDon
Pipe sizing link

3/4" !!!! 3/8" is more than likely all that is needed, or even 1/4" depending on the BTU requirements and the distances. (MBH = 1000 BTU per Hour) Less weight to drag around.

Personally I used copper, type L with flared fittings. Type K can not be used with flared fittings, too hard too thick a wall. We ran a class C RV for a couple decades. It had type L copper from the factory. Ran it over all sorts of gravel and back roads and never saw any crush damage from rocks. Not saying copper with take a direct crush between a rock and a hard place (steel frame), but that was my experience. If you use steel pipe do use the black variety mentioned or the special green coated stuff that can be buried.

If you do use threaded pipe use pipe dope /paste, NOT teflon tape. Depending on the care in installation bits of tape can end up inside the pipe and plug small gas orifices.

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 6:42 pm
by Redneck Teepee
I would run 1/2" black schedule 40 the length of the trailer then use adapters to transform to a propane rated flex hose at both ends for the final connections. Just my 2 cents worth. :D

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 6:54 pm
by RVServiceGuy
Black pipe always rusts though. It would cost more but what about stainless steel pipe?

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 7:06 pm
by bobhenry
RVServiceGuy wrote:Black pipe always rusts though. It would cost more but what about stainless steel pipe?


How many hundred years was that rusted thru black pipe in service? :shock:

Rusted clean thru ? :?

The chuck wagon has 1/2" black pipe front to rear. Adapted from a black hose requlator assembly at the tank and I used a flex gas line just like the one behind your gas stove in your home. It runs to a 3 burner stove with oven. I am certain 3/8 black pipe would have been adequate but curiously the 1/2" fittings were actually cheaper than the 3/8" so being cheap I went with the 1/2"

I have used flared copper fittings for water , gas, and hydraulics. I will take steel pipe any day over copper.

Just my nickles worth ! :roll:

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 7:17 pm
by Redneck Teepee
RVServiceGuy wrote:Black pipe always rusts though. It would cost more but what about stainless steel pipe?


Not in our lifetimes, if you live where they salt the roads the salt will eat the Stainless, stainless will hold up to the strongest acids, but not salt, black pipe has better salt resistance than stainless.

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 7:27 pm
by MtnDon
Black may eventually get surface rusted. But it will take a long time before it rusts enough to cause any safety issues. The black is just thin paint. Once assembled it could be primed and then painted. Do NOT use galvanized pipe for fuel gas lines.

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 7:27 pm
by MtnDon
Black may eventually get surface rusted. But it will take a long time before it rusts enough to cause any safety issues. The pipe walls are probably thicker than the steel frame the trailer sits on.

The black is just thin paint. Once assembled it could be primed and then painted. Do NOT use galvanized pipe for fuel gas lines.

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 8:17 pm
by RVServiceGuy
Good to know guys. I guess it all boils down to my ocd attention to detail and aesthetics

Re: What size Black pipe for propane?

PostPosted: Thu Feb 05, 2015 8:55 pm
by Shadow Catcher
Black/un galvanized steel pipe is the old standard but a pain to work with and CR came with BI and the under the axle drop was just waiting to catch a rock. RVIA standards also allows the use of copper, so I did. I check All of the joints each year for leaks. Flex copper a LOT easier to work with.