Shop Air Lines

[JB4310]

What pressure are these blowing at? I've seen PVC get brittle not sure what causes it, age, UV but can't be good for it's intended use of Plumbing either. PVC pipe has a pretty high pressure rating but you have to use the schd 40 fittings to keep the rating throughout the project, as opposed to the DWV fittings which have shorter glue hubs.

 

[ray66v]

130-175 psi, all sch. 40, sometimes even sch. 80 fittings.

With the exception of the attachment to compressor, and the pipe to NPT adapters for hoses, in my experiences, fittings were not usually failure points. Solvent welds were never failure points.

We have a retired Master Plumber, who was a Mechanical Contractor, and another guy, who is a plastics Engineer, in an origination I belong to, and they both will agree: PVC is good drain pipe, (although a little noisy), not good for pressure pipe.

 

[eddy622611]

I've never seen copper air lines. It would have to be cheaper than black iron if you consider labor. Is this the same copper tubing with sweat fittings that you would run for water lines? Thanks eddy622611

 

[Scooby074]

I would avoid Pex and PVC. There are nylon type lines as mentioned already that are designed to handle the pressure and oils etc for pneumatic service. Aluminum is also available. It is REALLY nice, but kinda spendy in the larger sizes. Check with a local air compressor (ie:speciality) store. You'd be safer just slinging an old rubber air line than using pex in my opinion.

I have 3/4 black iron. Running it isnt that bad. Just keep it sloped so condensation will drain and try to come out the top of your T for any drops. Also extend the drop past your T where your taking off the air to give the condensation a place to run into so it dont go into your hose. A inexpensive threader can be had at your local chinese importer for well under 100.

Only other thing id recommend is to oversize your line. I did the calculations and speced mine out to be 3/4, but i really should have ran 1" to get the best flow.

 

[kennyd]

I've never seen copper air lines. It would have to be cheaper than black iron if you consider labor. Is this the same copper tubing with sweat fittings that you would run for water lines? Thanks eddy622611

Yes, same stuff, but the "L" copper, not the very thin walled stuff (M).

 

[MrWoodChips]

I've never seen copper air lines. It would have to be cheaper than black iron if you consider labor. Is this the same copper tubing with sweat fittings that you would run for water lines? Thanks eddy622611

I did my shop in type L copper. Not that hard to do, just standard sweat fittings. Some of my quick connect couplers leak a little air, so I've got ball valves inline to leave only the line that I'm currently using charged with pressure. I've got a piece of flex hose from the compressor to a connection on the wall.

One thing I find incredibly useful is a portable air tank, hooked to a quick connect. I normally keep it shut off, but frequently enough I find myself in the need for air, farther away than the 150 feet of air hose that I have will afford. 10 gallons of air under pressure is enough to do a lot of things, like pump up a few tires, blow out a water line to prepare it for winter, etc.

John

 

[IXLR8]

I spoke with an engineer at a PEX heating tube manufacturer and he was surprised/horrified that folks would use PEX for high pressure air. At least their's was only rated for 100psi, to be used in a 30psi max heating system. PEX has a 30day exposure limit to UV, after that it breaks down to the point that the pressure limits are no longer valid. Having seen what PVC can do when it breaks... my shops air lines will either be 'L' type copper or iron pipe. Standard iron pipe lengths will work for me for the most part.. if not, Lowes/Home Cheapo will cut and thread it to the length I need.

 

[JB4310]

I've got a mix of copper, rubber and the new flex plastic,
never done any with iron pipe but if it's a straight simple run then I guess it would be fairly easy and surely durable.
The next one I want to do is a wild run up and over walls and through crawl spaces etc. any kind of pipe would be very difficult, I'm gonna use that flex stuff that was linked to here, I've used a little before, the stuff is great, the fittings are reusable and go together without tools. Not sure if it comes in the larger sizes though, the one I have is only 1/2" outside dia.

I also use valves to isolate the different runs and have a portable tank that I use all the time, seems I always have a low tire on something out of reach of the compressor.

Word of caution which I'm sure most already know, remember to shut off compressor when closing shop for any extended period of time, if a failure did occur causing a total loss of pressure and the machine kept running it wouldn't take long to overheat and cause damage or maybe a fire, I have a light that goes on with the compressor circuit that can't be missed when walking out the door.

 

[ray66v]

Cutting and threading smaller sized iron pipe is not that bad a job. If you plan the job out properly, you will only need to cut and thread a few pieces.

Then, either take them to the hardware store to get them threaded, or buy a hand threader from Harbor Freight for $30, it is not great, but, it will get you by.

There are some tricks you can use, and some really nice hangers, if you can find someone who has experience to help you plan it out.

 

[Flatheadyoungin]

kind of expensive but the garage pak stuff is quality.......quick too