"Mike Marlow" wrote in message
ink.net...

I wouldn't necessarily go quite that far yet Bob. Typically that mean
they
recommend against it for pressurized air lines from the compressor. In
other words - full working pressure lines that commonly reach above
150psi.
I'd look a little further before assuming that this application - Schedule
40 at 40 psi is included in what you read. I'm trying to think of some
application that uses Schedule 40 at these pressures on a regular basis,
but
nothing is coming to mind.

Its a judgement call, Mike and I agree its quite conservative. 40 psi is
the typical pressure for an old fashioned paint sprayer (not HVLP). One of
the factors would be how much volume is pressurized (= stored energy) at 40
PSI. He was talking about 4" pipe. That's uncomfortable to me. Another
factor is what type of joints are used. I'd be much more comfortable with
threaded joints as opposed to glued joints. I haven't seen the glue gun
contraption so I don't know how its put together. I think we've had enough
comment to allow OP to make his own judgement and I respect your opinion, as
well.

Bob