Planning on piping the shop to handle pneumatic tools (automotive, construction, woodworking types). I know the traditional material to use is black gas pipe. Is there any reason that PCV will not work? Cost is a lot less. Installation is a lot easier. But will it hold the pressure?
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You will get a variety of opinions on this one. But the consensus will be that you must NOT use PVC pipe.
Use black pipe, use copper pipe (Type K or L, not Type M), but never PVC. Under pressure it is brittle and, well can you say shrapnel?
David
Why not type "M" copper?
I think type M is thinner than the others. Type L is readily available and is only a buck a stick or so more. Mostly just passing on what I've seen here before. And my system is Type L copper, has worked beautifully for about 2-3 years now.
Why not type "M" copper?
I think schedule 40 is good for 135 psi, but as has already been said, PVC is a risk not worth taking. It shatters when hit with enough force, as opposed to metal piping. Black pipe offers the best all around set of performance qualities, but I find copper to be easy enough to work with.
I might use PVC if it was under floor or shielded in some other way, but I'd still go with copper for the exposed feed lines.
I used to work in a machine shop that had its compressed air system piped in Schedule 40 PVC. For water it was rated at, I'm guessing but the figure was much higher than the system pressure, something like 200 psi. One day a fitting split with a deafening report and threw shrapnel with such force that a piece went through 1/2" drywall after traveling 30' or so.
Only an hour before I had been working on the lathe directly in front of the fitting that exploded. In a typical country boy manner the boss shrugged of any suggestion of danger and calmly glued in a new fitting. I was deeply touched by the flagrant show of concern for his employees and moved on shortly there after.
You might try using pex if you really don't want to use black pipe. Try using Kitec brand of pex, it uses 3 layers - one layer of pex, a layer of aluminum, and a second layer of pex. Kitec is rated up to 200 psi and when you bend it into shape it stays bent.
Just a thought.
Thanks all. Went with the black pipe and feel good about it. I have enough things going off on their own without adding pipe fragments to it. Now, has anyone seen my air hammer?
I used 3/4" Parker hose and manifold it across the ceiling with several hang downs to hook up to. Parker hose is the best as far as I am concerned. I use it for all my hose needs. Its small and very flexable. It is kind of pricey but it is well worth it.
An Amish shop or 2 uses white PVC and say they haven't had any problems. But I think they may be using schedule 60. I am not sure on that . I like my Parker hose!!!
Normal PVC on air is deadly. However, there is a version that is rated for air; it is usually green in color. It is specially formulated to not be brittle. I think your best bet, dollar for dollar, is black iron. That's what we found when we did our new shop at work (pump/compressor/electric motor repair shop). If you go with anything non metallic, make sure that the oil in your compressor won't rot the pipe.
One small point that I haven't seen on this thread. Be sure to slope the runs of pipe and install drain valves on the bottom of each of them. Even the best filter and condensate collection units still allow moisture and crud to collect in the lines over time.