Permanent air lines

[pat32rf]

Long time ago in a past life it was explained to me why I shouldn't use copper water pipe for air lines. My memory's good, but short. Does anyone else know why?
Got lotsa 1/2 copper but iron pipe is a pain to thread. Its just for my own garage and basement....Plan on having about 125lb pressure.

 

[kennyd]

Copper is perfectly suitable for air line use. I prefer to use the "L" copper versus the "M" copper because it is thicker walled. Just stay away from PVC.

 

[Egon]

If materials are not purchased yet there may be flexible plastic lines and connectors that are suitable for air use.

No idea as to cost or availability.

 

[atgreene]

Most heavy trucks have copper air lines, or at least pieces of copper.

 

[Scooby074]

personally, I dont like copper. Mid wall copper is all right i suppose, but you need to use the right fittings, or its only as strong as the thin wall. And heavy wall wont be much if any cheaper than black pipe.

My system is plumbed in Black pipe.

THere are new nylon flexable systems available. One is called Rapidair. Last price ive seen was around $79 for 100ft. This doesnt include any fittings. Certainly a lot quicker than pipe though and likely cheaper when all is considered.

Theres also aluminum pipe, called Garage Pak, but you should be sitting down when you get the price.

 

[CurlyDave]

The only real drawback i can think of is that you will have solder flux in your air supply for quite a while.

The flux is water-soluble and flushes out of water lines quickly, but it sure isn't air-soluble, so a little bit will be coming out for a long time.

I have always wondered about the need for hard-plumbed air. I tend to put my big compressor in the garage/shop and leave it there. Rubber hose gets me everywhere I want to go. For air somewhere else, which can be another room, a job site, wherever, I have a portable compressor which can go anywhere.

 

[Scooby074]

My system is a single run to all points of use.

Im wondering if i complete the loop around the perimeter of the barn, would i have more volume at each point of use? or is it a waste of pipe?

 

[EddieWalker]

I'm with Dave. I have two regular, ruber hose lines coming off of my compressor. One line goes out through the wall and is kept on a garden hose type holder. The other line is inside my shop, and is also stored on a garden hose holder. The outside hose is 100ft long and I can get to any of my tractors with it. The inside hose is 50ft long and can also get to any location inside my shop. If I wear out a hose, or cut one, it's a simple matter of buying another one. My long hose is 20 years old, but short line is five years old. The only reason that I can see for hard lines around a shop is if there are multiple people using the air and you need the tools available for them in each area of the shop. For me, and what I do, it's never been needed.

Eddie

 

[PILOON]

I had an aviation facility with multiple work bench stations.
We ran copper to each bench with 2 fittings at each station.
Dual as we used rivit guns and air drills.
At each dual station in we ran about a 6-10 inch drop (sump) with a valve to act as a sump drain and as well draining the compressor daily.
That installation served us well for 10 yrs or so without any problems at all and the compressor was a monster with mega CFM's as well as sustained over 100 PSI.

 

[hydrovane218]

I have been in the compressed air service industry for almost 17 years. My two cents is as follows.
I have done my share of piping, copper and black malleable schedule 40. Not having priced stuff recently, one would naturally assume that copper would be more in materials, but is easier for the average guy without a threader to do. I haven't ever had copper burst or blow apart at the joints.
The advantages to copper are:
1/ It doesn't rust so it won't bung up your tools downstream
2/ It doesn't rust so it won't restrict air flow over time by reducing the inside diameter of the pipe
3/ It transfers heat better so you will have more moisture removal downstream during more moderate work loads(assuming you have a filter/trap at point of use)
The ideal way to pipe is in a loop from compressor, around shop, and back to compressor in order to eliminate noticable pressure drop. In most cases for a small shop and a small compressor, this may not be a noticable advantage. Also, the extra pipe, especially in larger sizes like 2", increases system volume which is easier on a cycling compressor like a piston, as it will run slightly longer and stay off longer.
While a long hose directly from the compressor may get the job done, it is a pain to constantly roll/unroll the hose, especially for the quick jobs like blowing something off or filling one tire. With a piped system and multiple outlets, a much shorter hose can be used in most cases.(and it looks much better/neater)
One way or the other, we all seem to get the air where it needs to be in order to get the job done.