On Tue, 10 Mar 2009 09:30:09 -0700, "Bob La Londe"
wrote:

Most shops I have seen use iron pipe for air, but I was just looking at a
couple on-line specs sheets on PVC and it looks like if I were to distribute
air at 125 PSI in my shop using 1" Schedule 40 PVC I would have about a 30%
safety margin at the worst case scenario. That's based on 120F operating
temperature. While yes it does hit 120F here in the desert once in a great
while I don't think its ever gotten above 105 in the shop building. Better
safe than sorry though.

Wadda ya think?

P.S. I have seen other shops use PVC also, and they said they never had any
problems.

The only real issue I see is that "wish this hose was 2 inches longer"
factor. I could probably mitigate that by using brass fittings at the ends
and securing them properly at the wall, and of course the fact that there
would be air all over the shop instead of in one corner would help quite a
lot.


Bob..at least once a year, I get called in to replumb a shop that had
PVC pipe that decayed due to compressor oil, heat etc etc and finally
blew out, often taking entire banks of florescent lights off the
ceiling, blowing **** everywhich way etc.

Im not telling you not to do it. Ive seen some up for as long as 10
yrs with no explosions. But each and every piece Ive taken down had
the structural composition of a grahm cracker. Drop it from 3 feet
and it shatters like glass.

If you put up PVC...every bit has to be firmly secured to something
rigid. After a couple years...putting any strain on it, thumping it,
tapping it, pulling on it..and its gonna break. With luck, no one gets
hurt.

Just my .02USD worth. My own home shop, is salvaged black pipe,
mixed with air hose all running into homemade manifolds with taps for
QDs all over the place. Only in places that I need a LOT of volume,
such as die grinders, DA sanders and so forth, do I use a lot of
pipe.

Black pipe is cheap if you buy it at a wholesale plumbing supply place
such as Ferguson Express etc. I think Im paying $11 for a 20' joint of
black. One of the tricks in doing a shop is to never ever use 90'
elbow. Only use Ts and plug off the unused side. Sooner or later, you
will need to put in another run or valve or line there.

Last year, I ran 3000+ feet of pipe air lines in (2) shops, one being
35,000 sqft, the other being about 10,000 sqft, but in 4 different
units of a "industrial strip mall", and installed 4 screw compressors
and a couple piston pumps total.

Its one of the things I do to make a living..and Im quite qood at it.
Ive turned down jobs where they wanted PVC. I dont want the liability.



Gunner

"Human nature is bad. Good is a human product*
A warped piece of wood must be steamed and forced
before it is made straight; a metal blade must be put to the whetstone
before it becomes sharp. Since the nature of people is bad, to become corrected
they must be taught by teachers and to be orderly they must acquire ritual
and moral principles."
—Sun Tzu
*