Pipe for airlines

[Jonathan Spool]

OK! Got the dust collection thing all figured out. Now I'm working on the layout of the compressed air system. I have Rapidair hose and manifolds from my previous system. For the new shop I plan to run a loop from the compressor around the perimeter of the shop with 1/2" pipe, which is sufficient for my needs (under 20cfm). The loop will be teed from which I will have drops down the walls using the rapidair system.

My question is why use black pipe for air systems rather than galvenized pipe? Is it just the cost savings of black over galvy, or is there a reason that galvy pipes and air don't mix?

[Ken Garlock]

I used 1/2" type L copper around my shop. The compressor is in another room to cut down the noise, and it is noisy.

To me copper is much easier with which to work. It certainly is much lighter weight, and type L 1/2" copper can handle over 600 psi.

Keep us posted on your progress with the new shop.

[David Woodruff]

I have used 3/4" plastic high pressure water pipe since 1995, no problems. My compressor is an Industrial strength., 5hp stand up. Pressure set at 130 psi. Plastic is cheaper and easier to install. I did fabricate from 1" black iron a vertical drip leg and also extended that horizontally for 6 feet with a slight incline to the vertical piece. The rest is about 50 feet of plastic. Black iron is used industrially, other than strength, to act as a water condensate as plastic is not a great conductor of thermal energy. I have not heard of a reason for not using galvanized. I can sort of visualize a small electrical current that might exist in a moist pipe interior that would greatly increase the oxidation rate of iron, which would not exist in uncoated black iron. At any rate I have installed a double air/water filter at the tank. As a precaution I also filter again at the spray gun supply using a silica gel canister. I am an advocate for plastic pipe and have experienced nothing adverse in its use. It is also easy for future modifications as the need is surely to arise.

[jerry nazard]

Another vote for 1/2 copper.

[Glen Blanchard]

Anyone try this? I was hoping to use it for my new shop when I get done with all the other stuff. At first glance, it appears to be easy to install.

http://www.rapidairproducts.com/

I am editing this post to be a bit more concise. I was referring to this company's product called "Rapid Air" (they have 2 other similar products). It looks easy to install and inexpensive. Below is the link I should have provided above.

http://www.rapidairproducts.com/rapidair.asp

[Cliff Holmes]

David, I appreciate that you haven't had any issues with using PVC for air. But it's pretty well-documented that it's not safe. My dad had several scars on the side of his face where a PVC pipe exploded in his shop. Next day we ripped it all out and put in black pipe.

Yes, PVC can work just fine for many years. But it can fail because of cold or UV degradation. And when it fails, it fails explosively and throws shrapnel at high speed. Metal pipes rupture rather than shatter, so you don't get any bits flying around.

[Callan Campbell]

David, I appreciate that you haven't had any issues with using PVC for air. But it's pretty well-documented that it's not safe. My dad had several scars on the side of his face where a PVC pipe exploded in his shop. Next day we ripped it all out and put in black pipe.

Yes, PVC can work just fine for many years. But it can fail because of cold or UV degradation. And when it fails, it fails explosively and throws shrapnel at high speed. Metal pipes rupture rather than shatter, so you don't get any bits flying around.

Cliff, although I totally agree with you, I wonder if the poster was referring to Polyethylene or some other type of plastic since he didn't mention PVC by name. I like Black iron, have used copper and galvanized pipe as well.

[Tom Welch]

Cliff, I don't think David is talking about PVC pipe. There are several types of industrial plastic pipe and tubing with normal pressure rating from 100 psi up to over 500 psi and it is designed for a 4 to 1 safety factor. (meaning under ideal conductions and new, a 500 psi tubing would burst at 2,000 psi.) The good thing about the plastic is no corrosion. Personally I would go with stainless steel tubing. But then I have a fluid power background. It is very expensive though.

[Ian Parish]

I debated this and researched this, in the past I ended up with an extra flexible air hose permanently connected to the wall to wrap around the shop. Easy and cheap, I bought Goodyear hoses at HF.

In my new shop I am considering running copper pipe from the compressor room to a couple of main connection points in the shop and then figuring it out from there. I have a few 10-15 feet of copper pipe left over from a new AC install at my place last month. I will start with this and then get a second mortgage to buy the rest of the copper pipe.

From what I understand Copper pipe will split if the pressure gets to high. PVC pipe exploded and sent shards in every direction if the breaks with under pressure.

If I was to run black pipe I would call my gas line install guy. He could pipe anything I needed at reasonable rates.

Ian

[Mitchell Andrus]

Oooooh. You mean air lines.

That's funny. I really thought you worked for an airline and they discovered or invented some kind... never mind. I got a laugh.
.

[Karl Gabel]

Check out the link below - these guys' applications are for automotive work but the suggestions are good:

http://www.tptools.com/StaticText/ai...ng-diagram.pdf

Black pipe.

[Matt Meiser]

I used copper originally but added a new run a few weeks ago. I decided to give PEX a try. Its not rated for air, but some searching on the internet found a lot of people using it successfully for home shop use. If it fails, it doesn't throw shrapnel like PVC. And if it fails I'm only out the cost of the pipe as I can cut the fittings out and save them for future use.

[Chris Damm]

My question is why use black pipe for air systems rather than galvenized pipe? Is it just the cost savings of black over galvy, or is there a reason that galvy pipes and air don't mix?

To answer your question...I believe it is because the coating can flake off on the inside of the pipe and clog your airtools. At least that is what I was always told.

[Walt Nicholson]

Pex has a product (PEX AL) that has an aluminum inner layer and is designed for air up to 200 psi. It is fairly flexible and you don't need the special PEX tools for the fittings. They use a ferrule type of fitting with an added o-ring. You can put everything together with a pair of crescent wrenches (or the appropriate sized end wrenches if you are picky) and you can take it apart again just as easy for moving/additions, etc. I bought a 300' roll (smallest I could find at the time) of 3/4" for under $150. The fittings are a little pricey but I used black iron elbows, etc. to save costs. No affiliation just found it to be a good product.

[John Pratt]

Everyone has their favorites, but I don't see a need for iron pipe with all the new products out there. I use the Simplair system piping from Ingersol Rand in my shop http://www.ingersollrandproducts.com...px-am_en-33037. I have about 200" feet of this stuff running throughout the shop with 10 drops (installed 1 year with no leaks). It is incredibly easy to install with no soldering (although I used to have copper and it wasn't too bad). The lengths of pipe are easy to cut if needed with a standard copper pipe cutter or imp. The quick connects/disconnects are the best part because if I need to change a drop it it justs comes apart and reconnects like tinker-toys (for those old enough to remember a time before video games. I have no affiliation with IR, but I am a very satisfied customer.