Shop air lines - in-the-wall or surface-mount? PVC? Copper? Titanium?

[widebody911]

Ok, I finally passed my frame inspection and I'm insulating my new shop this week. I've been toying with the idea of running the air lines inside the wall. I'm also thinking of using PVC (Schedule 40?) but I've read tales like "a friend of my uncle's hairdresser did that and the line cracked and..."

So, those of you who've done this recently - how did you distribute compressed air around your shop?

[MovOvr1]

I would recommend black pipe...it is easy to use and you don't have to ever worry about it failing...especially if you are putting it behind the walls.

Brian

[911Rob]

My shop is done with surface mount rubber hoses, but I never thought of using anything else? I've always ran the rubber hoses.

I'm trying to think of what kind of lines we used when I built some garages a few years ago, but can't.

Let us know what you decide and good luck.

[911pcars]

If it's not going to be accessible, use black iron pipe. If it's going to be accessible, use black iron pipe.

Sherwood

[toolman]

I used black pipe and I would NOT put it behind the wall just in case you have a leak, you will not be able to tighten it up plus it will leak water (from condensation) behind your wall. This would make any termites in the area happy. Make sure you install drops with drains, and angle the main (manifold) pipe so the lowest point is the compressor. This will insure all moisture will drain back into the compressor so YOU can drain it from the valve on the bottom of your tank. Do not hard pipe it to your compressor, use a section of rubber hose to take up any vibrations so as not to stress the pipe. Let me know if you need pictures.

[73911guy]

I've worked as a facilities engineer for a large corporation and I wouldn't think of using anything but black iron pipe. PVC pipe and copper tubing just aren't made for the kinds of pressure shocks that 100 psi air can make in the piping. In fact, if I visited your garage and saw that you had used PVC or copper tubing, I'd be looking for a way out rather quickly. I'm just not into taking a hit of shrapnel that will happen when the tubing decides it has had enough. Those of you that are using PVC or copper and say you've never had a problem are just living on borrowed time.

Jim

[widebody911]

So, what do you guys think of black iron pipe?

Wow, I haven't seen this sort of concensus since the "do you like oxygen?" thread.

[Chuck Moreland]

I'd surface mount black pipe. You will likely be making additions/changes and leak repairs later and surface will be much easier to live with.

Plus, you need to think about condensation. Unlike PVC, metal does a decent job of cooling the air and drying it out if the runs are long. Plan carefully the condesate flow and drain valves.

Buried in the wall, you won't cool as effectively.

[NY65912]

We only use galvanized steel for pnuematics. Costs a few bucks more but is always the spec on commercial and institutional jobs. PVC has a satic electricity build up problem and needs to be grounded by wrapping a piece of bare copper wire around it and ground it to an electrical ground. Black is good but can eventually rust out due to water traps.

My 2_¢

Mike

[73911guy]

So, what do you guys think of black iron pipe?

Wow, I haven't seen this sort of concensus since the "do you like oxygen?" thread.



We just want to keep you around awhile longer.


Jim

[3.2 CAB]

When I built my new garage, I used 3/4 galv. pipe. The main reason is that I never wanted to be bothered with it again. I installed lever ball valve drain traps on the down pipes below the quick disconnect. I would never think of using PVC nor copper tubing for high pressure air lines.

[HawgRyder]

Black pipe will last for 20 years or more...but no matter what you go with...make a fairly tall vertical run from the compressor to the system.
This means, as the air comes out of the compressor it has to take an upward run to get to the horizontal pipe.
This will give you a trap for most of the water in the system.
If the entrance line to the system also has a downward running line almost to the floor, you will have an extra place to put a drain valve.
In the systems we put in for the factories....the vertical line was very large (10" or more) in diameter, and had a cold water line running through it all the time....this cooled the just compressed air and made the water run back down to the automatice drain valve.
A cheap auto valve can be had from the trucking industry (the one that clears water from the brake air lines).
Cool dry air is very important if you are goint to paint with it, and also to keep your air tools from rusting.
Bob

[Benson]

Hello Thom!

I am a general contractor. I have experience working in a shop with compressed air and installing it.

I installed a 220v Compressor and Compressed Air Lines throughout a medical building. You can get away with PVC (plastic) but if you have an inspection by the Building Department or the Fire Department, where I come from, they will not be happy. PVC has been known to deteriorate and EXPLODE. They might refuse you a permit. I have never seen copper used. Galvanized is not good from a Building Code perspective - it can be mistaken for Fresh Water supply lines. That is what it is usually used for. If someone mistakes it for a water line and theirs an accident you could be liable. Also their is a flash point (fire if their is spark) to the Galvanized Coating of Galvanized Pipe.

BLACK PIPE is the way to go as many other's who like Porsches have said. When I installed Compressed Air in the medical building I used 3/4" Black Pipe and Gas approved teflon tape for the joints. I ran the lines over head in the Attic. I then stubbed down a short piece of pipe along the wall to the point of use. All the Pipes were exposed for tighterning or for future modifications. There is a collection of water in the air lines like Toolman and Chuck said. At ever quick release or outlet I stubbed in a nipple (short piece of pipe) with a bleeder valve. It is VERY IMPORTANT to do this. If there is excessive water in the line it will get into any of your tools and could damage them.

SPECIAL ALERT!!! WARNING! Be carefull if you bring an air nozzle close to your eyes or ears to spray dust or something off. You can damage them very easily...

Hope that helps, and good luck!

My Faith is built on nothing less than Jesus Christ.

Benson :cool

[no substitute]

My understanding is that black pipe would work well. I just draped the rubber hose through a couple of ceiling mounted eye hooks. I do yearn for black pipe though.

[Jim Savage]

From experience in our lab at work........DO NOT USE PVC!!!!!

It will crack, and the joints will come loose and start leaking within 4 years. We are now in the process of replacing all the lines with black pipe. (I'm glad the lines are on the outside of the walls...hint hint).

Jim

[mtburman]

why not just put a 50' hose reel next to the compressor, if not, run copper. Black pipe will rust from the moisture being picked up by the compressor, also easier to run as no threading. Also put in an oil capable regulator at the end so you won't have to oil your tools.

[wilke3169]

I was wondering when someone would comment on copper. Type L copper with silver solder will withstand any pressures used in a shop or home garage application. This piping is used throughout the HVAC industry where pressure temperature changes far exceed any that will occur in an air system.

[david914]

Ditto on using type L copper. I would think that properly installed, type L copper would be more than adequate for the job. Also, it would be much easier to work with (assuming that you know how to solder pipe). Copper is used extensively in the HVAC industry where it sees much more pressure than it would in a compressed air distribution system. Just food for thought (or debate )

[HarryD]

have been a facilty engineer for over 25 years. black pipe or copper is the only way to go. Plastic pipe is a bomb wating to explode.

[widebody911]

Hmm. Copper, eh? I've never worked with it, but I've watched. Doesn't look too difficult.

My compresor actually lives outside in a little shed, and I'll be running piping thru the ground and into the side of the garage. Galvanized owuld probably work best for the in-ground stuff, and then either copper or galve/block pipe inside.