Pressure testing CM870

[Hammerhead]

(11-03-2019 )Lonestar10 Wrote:  I built all my tester out of pvc figured if the glues good for 60-90 psi water good enough for 20-30 of air. Just drilled/tapped the caps for pressure regulator then put a washer and retaining nut on inside of pipe on regulator then glued and clamped boots on them

(11-03-2019 )Rawze Wrote:  just a word of caution on PVC...

Never ever assume that since PVC can hold 60 - 90 psi of water, will it hold the same in only air pressure.

I have seen many many PVC pipes explode and it can put you in the hospital or kill someone. i goes off like a stick of dynamite. - seen that mistake so many times in machine and mechanics shops where they cheap out and use PVC for their air supply, it is not even funny.


20-30 psi, not too harmful, but don't expect it be anything near safe with higher pressures.

one thing to remember, PVC is made for pressurized water, not air...
water DOES NOT compress (in volume), so pressurized water is the equivalent to one volume of said pipe volume. upon release of pressure, aka a failure, as soon as the compressed solid escapes teh confines of the pipe, the release event is over...and yo have a water leak.

however, let us not forget that boyle's law tells us that in an ideal gas, pressure is relative to volume! so its not the same thing as a compressible solid/liquid...30 psi of air is 3 ATA, or twice the volume of said same pipe volume, so upon said failure, you have THREE TIMES the volume yet to escape...yes that means the release event becomes violent...exponentially so! take that same pipe and pressurize it to 90 psi, and you've now doubled the 3 ATA to 6! that means 6 TIMES the volume of said pipe to escape the failure!!! in other words the release event can safely be described as an explosion!!!

remember kids, science is fun...but it can be dangerous!!!