Compressed Air Distribution Systems (air lines)

[Wingnut65]

R6 Racer, Thanks for the link to the layout diagram. That gives great info.

jhchoppers, Thanks for the OSHA research. That says it all.

mustangmccance, Nice install of the air lines. Love the size of your workshop. Two compressors and three garage doors!

OK, PVC is out! But, what is in!

There are many flex line systems that are made just for running compressed air around a shop as we have seen in this thread in kit form and installed. But, I am interested in running a line from the front of my garage to put a reel between my two garage doors, I want to run it thru the attic space so there is no exposed line hanging below the drywall ceiling. I will go up the wall, 90 degree bend, thru attic to front, 90 degree bend down thru the ceiling to a 3-way manifold for the reel and spares. I will also have a drain valve at each low point.

What would be the best - Copper (the thicker walled, Type L), Threaded Galvanized Steel Pipe, or Threaded Black Iron Pipe?

Is there a reason not to use one over the other?

Any words of wisdom will help us move on from 'No PVC' advice to advice on what we should use instead.

jeff

 

[Torque1st]

Metal cools the air to separate the majority of water vapor from the air. Without some sort of refrigerating system and desiccants you will not get the moisture out. Plastic materials are useless for removing water. The cooler the ambient air is around the pipe the better. Placing the pipe behind sheet rock or in insulation is counterproductive.

Threaded black iron(steel) pipe is the standard used by professionals. It sometimes has problems with rust and many people seem to erroneously think you must have a pipe threader to use it because the pros do it that way. It is also called out by reference to mechanical codes contained in building codes.

Galvanized steel pipe is an alternative but some say you get flakes of Zinc galvanizing material from it. Many people seem to erroneously think you must have a pipe threader to use it also. Some codes prohibit it for anything but water (codes vary).

Copper tubing is another alternative but check with your local code authorities. Some places do not allow copper due to fire codes. Copper must have brazed joints, not soldered with plain plumbing solder. Brazing material, flux, and corrosion can also cause particulates in the air stream.

Use filters for all three materials at the point of use.

Which one is "Best" is determined by local codes, cost, preference, and your skills.

 

[xJoey Dubsx]

I was thinking about doing this with some line and fittings from Parker..

 

[akdiesel]

I was thinking about doing this with some line and fittings from Parker..

I say go for it. I did mine out of Swagelok fittings and pipe. It has been in service for over a year now and no issues. You can get some good deals on the parts and the pros out way the cons for me, versus the other choices out there.

 

[trloh]

I saw this today. I do not know the brand but it was professionally installed about three years ago. Since this mishap with the fitting I understand other fittings have been "improved" and since replaced.

This is not to bash the brand just to give everyone something to think about when dealing with shop air.

Luckily this happened when the shop was closed and no one was in the area and it was also in an isolated area. When the fitting let loose the tubing swung around as it swiveled and punctured the wall.

 

[ket-tek]

^^Looks like Prevost stuff, supposed to be quality products. Most likely an installation error on one of the fitting seals, not really a fault of the product. But could have damaged alot more or hurt someone if in a different location.

But I still prefer all threaded brass or iron over o-ring seal or ptc fittings that are becoming so popular these days, mainly for fast installations I guess..

 

[Dragster Racer]

PVC...PVC...PVC
I wouldn't suggest using it, but it sure does push some buttons around here!
I finally have most of the leaks out of my HF pex system. Replaced a couple of fittings with hardware store ones. I really don't think that most uses will have a problem with the 3/8". I have only run into one: Fillilng my portable air tank. It takes a little longer than I would like, and I think the 3/8" is the restriction. Die grinders and other air tools seem to be just fine though. Oh..one more for good measure: PVC
LOL!

 

[speedoo51]

Just a note...I bought a couple kits from Summit Racing, similar to the HF and Rapide Air kits...What a pain to get the fittings to seal!! Mainly because the tubing is out of round from being rolled up..Flow wise didn't seem to be an issue but I didn't use a DA. More bad, tube split about 4" out from fitting, at 60° and 100# which now makes every other inch of the line suspect...I plan to replace with copper, just have to think a little more as to routing..Maybe I'll keep the tubing for short runs, flex connections..

 

[speedoo51]

I saw this today. I do not know the brand but it was professionally installed about three years ago. Since this mishap with the fitting I understand other fittings have been "improved" and since replaced.

This is not to bash the brand just to give everyone something to think about when dealing with shop air.

Luckily this happened when the shop was closed and no one was in the area and it was also in an isolated area. When the fitting let loose the tubing swung around as it swiveled and punctured the wall.

HOLY S__T!!! Getting smacked with that line would've HURT..

 

[Tyler Williams]

I saw this today. I do not know the brand but it was professionally installed about three years ago. Since this mishap with the fitting I understand other fittings have been "improved" and since replaced.

This is not to bash the brand just to give everyone something to think about when dealing with shop air.

Luckily this happened when the shop was closed and no one was in the area and it was also in an isolated area. When the fitting let loose the tubing swung around as it swiveled and punctured the wall.

This is why our compressor gets shut down and drained every night before we go home.

 

[PaulR]

Here's an on topic question and hopefully not too much of a hijack:

Would you guys run your lines along the cieling where you can see them or take them up into the garage attic where they are out of view?

Maybe have a cleaner look in the attic, plus safer if a line blows. But more difficult for maintenance if they are up in the attic?

I'm leaning towards pex al pex or the equivalent kit.

 

[e-tek]

I just re-wrote this post. I was going to say I'd consider a plastic piping system with the manifolds as it seems easy to install and expand cost-effective judging by the cost of the parts shown below. HOWEVER>>>> I used black pipe and it's every bit as expandable, very cost effective, easy to expand (I just did with mine). Iron has the advantage of being a heat sink and will never have the short comings of being breakable. Plastic pipes do provide cleaner air though......

 

[Mike in Ohio]

Torque1st I am curious about needing to braze copper air lines. I haven't started mine yet but I have a bunch of copper left over from when I built my house that I was going to use. Why won't regular solder work?

I guess it might be time to get the oxy/acetalene torch out and learn to braze.

 

[R6 Racer]

While were talking air lines... copper lines, what about using 95/5 solder or is that a no no?

Steve

 

[csargents1546]

According to most if not all aircompressors, pvc is degraded in strength by the oil that is in the air compressor. I speak from experience, the previous owner of my home used pvc, I had intended to switch it out. One day while airing up my tire, a tee blew out and sent plastic pieces all over the garage. Needless to say the next weekend the whole system went in the trash and I plumped in black iron pipe. Never had a problem since. Just my .02 cents worth.

 

[Torque1st]

AFAIK regular solder lets go almost instantly in any heat/fire situation. When a compressed air line lets go what was only some overheated rags turns into an instant blast furnace. That reduces escape time for the inhabitants from minutes down to seconds. Mechanical codes call for brazed lines, not soldered. Some city building and fire codes do not allow copper lines.

UV, oil, solvents, etc degrade PVC, -but it is the material itself that is unsuitable for compressed air use. Degradation only makes it worse.

 

[Perry H]

So what happened to the Harbor Freight RapidAir knock off?

I probably wasn't going to use it, but just covering all my bases and I can't find it on their site.

Did they quit selling it, and why? Worked, but not profitable, or stunk so bad they even they didn't want to sell it?

 

[financer83rs]

I have air every where in my combine five bays of garage(s). I used 5/8" pex. I ran it undergourn to my unattached garage. All being fed from my compressor in the basement next to the furnace. Don't have to hear it run from outside. I have a fuse type kill switch in the garage for convienance.

 

[redcar]

When hooking up an air filter and an air regulator, does it matter in which order you hook them up -- that is, on the "compressor side" of the air line, can the filter come first and then the regulator, or should the regulator be "up stream" closer to the compressor? Thanks,

 

[SuperSocket]

AFAIK regular solder lets go almost instantly in any heat/fire situation. When a compressed air line lets go what was only some overheated rags turns into an instant blast furnace. That reduces escape time for the inhabitants from minutes down to seconds. Mechanical codes call for brazed lines, not soldered. Some city building and fire codes do not allow copper lines.

UV, oil, solvents, etc degrade PVC, -but it is the material itself that is unsuitable for compressed air use. Degradation only makes it worse.

I think when used as a sole garage application the furnace concept would not matter as your garage is already filled with very high combustibles. Your garage should also be fire separated from the home so it should not provide a very large issue.


Also, in rec garages for weekend warriors (you know, people who maybe uses their compressors once a week or less), if they turned the air off after each use (something you should do out of habit anyways), there would be no risk to fire.

Lastly, solder starts releasing at 183 degrees c. PEX for example will start having issues under pressure and hitting 180 degrees c... so PEX then would exhibit the same issues as copper.

I am personally looking at copper and PEX. I am not sure about black pipe as I do not want to deal with the issues of leaking. I shut my compressor off whenever I am not using it and would cut the air to the line in case there was a rupture. PEX to me has the better appeal. Worst case if it bursts I can replace it, it's super easy to route and run, so there is no real issue as if it was rigid pipe.

 

[Torque1st]

The filter goes first to protect the regulator mechanism from particulates.

Use a filter/regulator at the point of use if required.

 

[redcar]

Thanks, Torque1st -

Redcar

 

[BarnFab]

Just a question on this stuff, I have been using Blue Band Poly Pipe for years but don't see it mentioned. This is the stuff you see in high presure irrigation and more recently in new houses for hot water etc. It comes in many sizes and I have been using 1". It is cheap, flows well and you can get a lot of fittings / elbows etc.

It is presure rated to over 200 PSI, just wondering why no one else mentions it, any issues with it ?

 

[BarnFab]

Here is a link to some guys in Australia, seems pbase presure is at least 6.3 MPA or around 900 PSI .... - http://www.polypipe.com.au/index.htm

Although maybe I am reading it wrong

 

[Stuart in MN]

Here is a link to some guys in Australia, seems pbase presure is at least 6.3 MPA or around 900 PSI .... - http://www.polypipe.com.au/index.htm

Although maybe I am reading it wrong

Looking at the link you provided, that particular manufacturer does have guidelines for using their polyethylene pipe for compressed air. It does appear you have to factor the sizing of the pipe differently for compressed air than you do for water or other fluids, there's some tech information here. http://www.polypipe.com.au/images/Design-PE.pdf

I don't know if US suppliers of polyethylene pipe have similar standards - as with any product it's best to check the manufacturer's specifications.

 

[MScott]

One of the most important functions of air distribution systems is the removal of heat (and coincidentally moisture) from the compressed air. My gut feeling is that copper and iron (both black and galvanized) would be much more efficent in this respect than PEX although I must admit that I have never seen actual figures to substantiate this.

 

[Kevin54]

Just a question on this stuff, I have been using Blue Band Poly Pipe for years but don't see it mentioned. This is the stuff you see in high presure irrigation and more recently in new houses for hot water etc. It comes in many sizes and I have been using 1". It is cheap, flows well and you can get a lot of fittings / elbows etc.

It is presure rated to over 200 PSI, just wondering why no one else mentions it, any issues with it ?

Wow...A Zombie thread

Anyways, what you are describing sounds like the same thing as PEX, but maybe with a different name. I would go with something like that, copper, or black iron piping for an air system. You could also go with aluminum but the price of it always seems to be higher than copper. Anything but PVC. With that and airline in the same sentence, look out because it perks up the ears of the lynch mob. And if you don't believe that, go buy some and post a pic of your assembly and see what happens

 

[digdug18]

Black iron pipe all the way.

 

[Steevo]

Black iron pipe all the way.

Ditto.

I ran mine with all 3/4" black pipe, all the way around the ceiling and all the way to the bottom of the drops.

 

[KaotiK TrendZ]

Yep this may be a revived from the dead thread, however it is a useful thread for those who are starting a new garage setup like myself and cannot afford to run copper throughout my garage. Well i am sure i could but for my use this would be a pain in the **** and i dont have time to mess with it. So with that being said.....

I will be running my rapidair system tomorrow if it isnt too damn hot in the garage. I need to invest in a fan or something haha. Just recreational use, as it will only be used on the weekends. Using the "1/2" inch but really is 3/8 inch. Will post up some pics sometime this week.

Also, Northern Tool here in Houston sells the Rapidair system kits. I paid $99 for 100' of tubing, double maniford, and two outlets with all the fittings. However for what I am wanting to do, i needed to buy some additional accessories and fittings to make it right for me.