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Old 2005-08-04, 1:08pm
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MikeAurelius MikeAurelius is offline
Safety ALWAYS
 
Join Date: Jun 10, 2005
Location: Sauk Rapids, Minnesota
Posts: 2,401
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Ummmmmm....

Ok, yeah. I see where your confusion might be.

Let's talk about the propane first. When propane is run through a wall penetration (I just love that word!), it must be encased in a solid metallic tube, not a rubber one.

Here's the outline of how the fire code wants to see the work done:

Propane tank - flows directly into regulator that is mounted in the screw fitting on the propane tank.

From the low pressure side of the regulator, mount a flexible metallic pipe (similiar to what is used for gas clothes dryers), and run this flex pipe to a shut off valve.

The shut off valve is mounted on black pipe, which runs through the wall.

We are now inside the building.

On the wall side of the black pipe, mount another shut off valve.

From the shut off valve, run any type of metallic piping, such as soft wall copper, to a "distribution point".

At the "distribution point" there is another shut off valve, which then connects to "T" grade hose for direct distribution to the torch or torches.

If you want to keep your oxygen outside, a similar type of process can be done for the oxygen line. There is no maximum pressure requirement for oxygen, so you can run as much O2 through this separate line as you need to.

Don't put PVC pipe through the wall and then run rubber hose through it. This is a violation of fire code.

When I mention black pipe above, it doesn't have to be black pipe, it can be any hard wall, non-flexible type of pipe, such as stainless, galvanized, heavy wall copper.

On the inside of the building, plumbing from the first inside shut off valve to the "distribution point", the piping can be anything metallic, from soft wall copper to black pipe, to stainless or galvanized. Most of the time, soft wall copper is used because it can easily be bent (use a bending spring) to conform to walls, corners and other obstructions.

All joints must be either threaded or flare fittings. Do not use compression type fittings. If you use threaded fittings, be sure to use teflon tape or gas approved pipe sealant.

On the inside of the building, if the main run from the shut off valve to the "distribution point" is longer than 20 feet, the line must have a sign indicating the gas that is inside the pipe and the direction of flow. There must be a sign every 20 feet. This lets fire professionals know what is in the pipe.

The "distribution point" is anywhere where the gas line converts to "T" grade hose for end-use consumption at one or more torches.

For transitioning from metallic pipe to "T" grade hose, use standard brass fittings, threaded or flare, with a ribbed hose end on the opposite side to match the internal dimension of your "T" grade hose. For example: 3/8" pipe thread on one side, 1/4" male ribbed hose end on the other side.

If the run is going to be long, for example, more than 20 feet, consider increasing the size of the pipe by at least one pipe size. The length of the run from the propane tank to the distribution point in my studio is about 35 feet (up a wall to the ceiling, across the hallway, and down the wall on the other side). I ran 1/2" soft wall copper from the inside shut off valve to the distribution point valve, then 3/8" "T" grade hose from the distribution point valve to each torch.

Larger than 1/4" diameter hose will increase the amount of available volume of gas, giving you more "flow" at a consistent pressure. This is especially important if you have more than one torch, and/or one large torch and several smaller torches. The larger diameter hose will decrease flame fluctuation as the large torch is turned on or off, or if the outer fire ring is suddenly turned on or off (like if you have a foot pedal installed).
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