(Craig) wrote in message . com...
Richard Lamb wrote in message news:


OUTSIDE air compressor room(!), and air piped around the shop?
Some people use PVC pipe for that, but I'm too chicken.
Mine is iron gas pipe.

I'll second putting the compressor outside the normal work area.

As to using PVC....well use it only if you like playing with bombs
with random length fuses... when it lets go, it becomes a shrapnel
generating machine. Also, let us know your shop location so we can
avoid being close to it.

The PVC and CPVC pressure ratings are for incompessible fluids only.
When you rerate the pipe using the correct formulas and apply the
correction factors for compressible fluid service and for operating
temps, you will find that the stamped 200 psi working pressure is now
about 4 psi.....

Now lots of people will pooh-pooh this and tell you that they have
been using it for years without a problem....just means that they
haven't had a failure yet. Take the time and read the exact working
of the ASTM rating stamped on that piece of PVC or CPVC as well as run
the numbers for yourself. I'll gladly point you to the specs and codes
as well as numerous vendor sites.

If you don't like this answer, then do a Google search on air and PVC
over in rec.crafts.metalworking. Lots of real world experience with
the failure side of PVC used as air lines over there.

Craig C.


Craig's right. We put pvc all through my hangar and forgot to glue
one joint after dry fit. It went off like a pipe bomb with a sharp
peice hitting me in the face after whizzing by the eyes of my friend
and bouncing off a wall. Close call. You don't want to use this idea
unless it's good new schedule 40 stuff and you put it in the wall
behind sheetrock on purlings or something. Even then you may have
just built yourself a ticking sheetrock bomb (I don't know.) If it
sits out in the sun with the door open, you're getting UV damage and
the failure will happen a lot sooner. Also we discovered that the
straight sections are only schedule 125: they were sitting in the
Schedule 40 bin at Home Depot. I can't believe that I fell for that.
I thought it was a new thin-wall formulation or something (no legible
markings on the pipes.) But the nice new looking extruded stuff is
just 125psi sprinkler pipe and I'm at about 110psi in the shop.
Between that and the green lumber I don't think I'm going to go back
to Home Depot. IMHO use iron water pipe. And don't screw around with
those cheap oil-less air compressors. They just never recover,
running up your power bill and making your neighbors deaf.