Anyone use PVC for compressed air piping??

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terrywerm

Keeper of the Coffee Pot
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Does anyone know of any reason to not use 1/2" Schedule 40 PVC pipe for plumbing shop air of 125 PSI?? The pipe is rated at 600 PSI working pressure. A neighbor did his shop with 3/8" CPVC, which is slightly different and works fine, but his biggest complaint is that he should have used 1/2" as he gets too much pressure drop, especially when using something that uses a high volume of air, and he's drawing his air from the end of a long run of that small pipe. Just thought I would see what experiences others may have had before I bite the bullet and plumb mine.

TIA,

Terry
 
i have used pvc sch 40 for air and it works rather well. the only drawback is that it gets brittle as it ages , especially if it is exposed to sunlight, ultrviolet light and ozone rich areas. it will last several years without problem but cpvc wou;d be a better choice in my opinion due to greater wall thickness, flexibility, and uv resistance. Schedule 80 might be a better choice also --richard
 
All I can say is, "It's been nice knowing you, Terry."

This subject has been beaten to death on all the other fora - some of them even have stickies for the subject. Do a bit of reading and then go out and buy some iron gas pipe or copper.
 
Just after I posted my question, I did some searches and found that it is not a good idea to use PVC for compressed air. Keep in mind that "not a good idea" is a very 'soft' way of saying "DON'T DO IT!!" Turns out that OSHA bans its use for compressed gasses here in the US. For the benefit of others who look in this forum for this information, I will post what I found out: The concensus is that PVC becomes more brittle over time, especially with exposure to UV light or ozone and will eventually fail in a catastrophic manner. With pressures in excess of 100 PSI, a shard of PVC can be propelled through a sheetrock wall 30' away. Not something I want to experience first hand or even at a comfortable distance.

With that said, I don't like black iron due to it's tendency to build up rust and crud in the lines, and copper is expensive, but I think I'll invest my money in either soldered copper or in the aluminum systems that are available. One other option might be to use DOT certified air brake line and fittings. Not sure about the cost comparison, but it might be a viable option that would also be easy to install.

Thanks guys!

Terry
 
You could use regular 12mm (1/2") polyurethane air tubing, the one they use to connect pneumatic cylinders. The black one is UV resistant.
 
Thank goodness. You've made a wise choice. We want you around on the forum for a long time.
 
Terry,

Here in the UK we tend to use flexible reinforced airline tubing for home shops. I piped my whole shop up in about 3 to 4 hours and put droppers wherever I needed them. Just drill a hole thru a wall and poke the pipe thru, same with shelves, drill holes in them to feed the droppers down. All held in position with nail on plastic clips.

We use 'tailed' brass fittings for T's and all other joints with a simple ring crimp.


Bogs
 
It looks like I will probably be leaning toward using flexible plastic air tubing, much like air brake tubing. It is easy to work with, and there are push to connect fittings readily available.

Thanks to all for their input!!
 
I used 1/2" flexible polyethylene. Worked very well, easy to install. If it blows out, it just splits open.

 
I don't know the specs on air brake tubing, but the fact that it has DOT numbers stamped on makes it much more expensive than the same material without a DOT number.
 
Just use the same air hose that you will be running to the tools. Barbed brass fittings are cheap and reliable, same with worm type hose clamps. That's what I did.
 
The main line in my little shop is done in soldered copper. Mostly to help get the water out of the air. 20' or 30' of copper and some up/down loops really help with that. Once the air gets closer to where it's going, I've plumbed out with rubber hose and brass barbed fittings hose-clamped on. or plastic with push-connects. I've been impressed with the ease and non-leakyness of the push-connects and probably will do more with that.
 
Just getting away from the main theme.

I also purchased some of the curly extending airline extensions. They are very reasonably priced, and now, by having 4 x 6 metre extensions, I can actually get air to any part of my small property, even upstairs in the house if needed. It was a godsend when doing my covered way, I could use all the air tools from my shop, drills, power files, grinders, screwdrivers etc, and no trouble using them anywhere, especially when it was raining. No curly hair for me.


Bogs
 
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