Back When I had my old Garage setup I used NEW 1/2" PVC.
I had cranked up the 7HP Craftsman 60gal. Compressor to 150 psi for prolonged periods with no problems.
Back when I worked at the CATERPILLAR dealer We had 3/4" and 1" PVC lines.
They were pretty old and one day at lunch break they all blew up with Shrapnel flying all throughout the shop!
No one was hurt due to the fact that we were all in the cafeteria eating lunch!
People have died using PVC pipe, that is why it is illegal. You do not know when it will blow. It ages and one day BOOM. If your standing there you get to be a statistic. Great for the kids, daddy was killed by air! When PVC gives, it explodes into shards and they are sharp like glass. I don't know about you guys but I would rather not risk it to save a few bucks. Guys who use PVC are usually the same guys that say "Here, hold my beer and watch this!". LOL Hawkrod
Hawkrod wrote:People have died using PVC pipe, that is why it is illegal. You do not know when it will blow. It ages and one day BOOM. If your standing there you get to be a statistic. Great for the kids, daddy was killed by air! When PVC gives, it explodes into shards and they are sharp like glass. I don't know about you guys but I would rather not risk it to save a few bucks. Guys who use PVC are usually the same guys that say "Here, hold my beer and watch this!". LOL Hawkrod
I have roughly 30 to 40 feet of 1/2" pvc ran in my garage with outlets at various places. So far so good. I'm good to go, I don't need anyone to hold my beer.
PVC pipe is perfectly safe if you design properly. PVC becomes brittle with the cold and soft with the heat, and it can fail in either condition. Don't put your piping in a place where it gets too cold or too hot!
Piping is available in several different schedule numbers, which indicate different wall thicknesses and different pressure capacities. Personally I'd use schedule 80. I'd also go to a relatively large diameter (maybe 2") so that it could store up more air - it effectively extends your reservior an extra few gallons. 2-inch schedule 80 is rated to 400 psi, I don't run my air tools at more than 90psi. Therefore, I'd have a factor of safety of 4.4, that's pretty good. If you wanted to feel even safer, give up the storage capacity and go to a smaller diameter. Even in extreme temperatures schedule 120 will hold pretty well.
Sorry you are wrong and the manufacturers say so. There is nothing safe about using something that the manufacturer and government regulators say you should not use. Using larger diameter tubing actually increases the risk dramatically and temperature has very little to do with PCV failure as most failure is related to stress according to OSHA. I would suggest that if you are going to post you should at least do some homework first. You could have easily followed some of the links and read them to educate yourself on the subject before making innapropriate suggestions. Putting yourself at risk is one thing but suggesting that others should do so is innapropriate. Hawkrod
here are some quotes from the companies that make the PVC:
"The Plastics Pipe Institute recommends against the use of thermoplastic pipe to transport compressed air or other compressed gases or the testing of such piping with compressed air or other compressed gases in exposed above ground locations, e.g. in exposed plant piping. It is recommended that all thermoplastic piping used to transport compressed air or other compressed gases be buried underground or encased in shatter-resistant materials. In designing thermoplastic piping to transport compressed air or other compressed gases, the strength at the operating temperature, the pressure, the energetics, and specific failure mechanism need to be evaluated."
"The main problem with using PVC pipe and fittings for compressed gas is not that it spontaneously explodes but that PVC is a brittle material that can be broken or shattered with external force unless properly protected. Compressed gasses can be best described as being analogous to a coiled spring. When a PVC pipe or fitting fails when under stress from compressed gas it literally explodes like a bomb, sending shards of plastic flying several feet in all directions. Liquids, on the other hand, being compressed by only 1/10th of 1% contain very little stored energy. When pressurized systems with liquids fail, the energy is dissipated very quickly, thereby creating a much lower potential for hazard.
Colonial Engineering does not recommend the use of PVC plastic pipe fittings in compressed gas service."
"The dangers involved in using rigid vinyl piping products for compressed air transport are well known in our industry. Numerous disclaimer bulletins and letters have been circulated for almost three decades. It will not surprise you to learn that our government has just recently recognized the problem. "
And finally the legal code:
sections 842.32, 842.43 and 849.52(b) of the American National Standards Institute/American Society of Mechanical Engineers (ANSI/ASME) B31.8-1986, Gas Transmission and Distribution Piping Systems Standard, limit the operating pressure of plastic piping distribution systems to 100 pounds per inch (psi) and prohibit the installation of such systems above ground except where ". . . the above ground portion of the plastic service line is completely enclosed in a conduit or casing of sufficient strength to provide protection from external damage and deterioration."
"Liquids, on the other hand, being compressed by only 1/10th of 1% contain very little stored energy. When pressurized systems with liquids fail, the energy is dissipated very quickly, thereby creating a much lower potential for hazard. "
Hawkrod, this is a very good point. A liquid is going to relieve itself faster due to the lower compressability.
"Gas Transmission and Distribution Piping Systems Standard, limit the operating pressure of plastic piping distribution systems to 100 pounds per inch (psi) and prohibit the installation of such systems above ground"
We're talking about low pressures here. I've never used air tools rated for more than 90psi. Even the standard you quotes allows for this, although only in buried or shielded applications.
"Using larger diameter tubing actually increases the risk dramatically"
I'm aware of this, as anyone could be that looks at the charts I cited. Don't feel comfortable with it? Go to a higher schedule number (120) and a smaller diameter; 1/2" schedule 120 is rated at over 1000 psi at room temperature! Even on a hot summer day you're not going to exceed the derated capacity of that pipe with 90psi.
"...most failure is related to stress according to OSHA." Probably more in the line of fatigue, which is stress cycling. Definetly a valid concern, but in low pressure applications where pressure changes are not sudden, and temperatures are not low, I don't expect fatigue life to be an issue.
The danger is not so much that the pipe will fail, but rather the way it fails. If you design safety into your system with high capacities, you won't have a failure. It is true, however, that PVC has a more dangerous failure mode than copper. Copper is relatively ductile so you're less likely to have any shrapnel in the case of a failure.
I don't mean to endanger anyone. I just think that under the right conditions using PVC is safe if you use your head and design for it. If you're not comfortable with it, use copper. I understand why there are some that disagree.
Sorry, cite some facts like I did. You are endangering people just by saying it can be done. Read what requirements there are in order to use it. Exposed PVC is not allowed by law. If you did build a system and tried to sell your house you could not. If you built a system and somebody got hurt your insurance would not cover you. There is reason for this. It is illegal to use except in very limited and restricted ways. Lots of people drive drunk and don't die and that is a perect analogy to this situation. a lot of poeple do it and nothing happens. Sorry one person injured is too many. You are recomending that people drive drunk because you never got hurt. Hawkrod
I'm running about 100ft of red rubber hose to a tee then another 100ft from the t in one direction and about 50ft to a retractable hose reel, no pvc, no copper, iron, just red rubber hose...
Just did my shop in Black pipe.
5 Drop downs, no leaks.
PCV isn't meant to handle pressure that high... sure it can.
Heck, your truck will do 100mph.... but do you want to keep it at that speed all the time? Also PVC DOES get brittle over time. Its a plastic. Eventually that just gets ugly.
Personally I though that PVC was more expensive than black pipe?
Think I did my whole setup for under $200. Just borrowed my buddy's threader and went to town.
Best improvement I made in March this year. (been a lot of improvements)
Just my
-=Life's Too Short to Drink Cheap Beer=-
1973 F-100 Custom Sport (Previously had 1967 & 1970 F-250)
Yep, did the 1/2" copper loop around the top of the garage wall with drops all over the place. I have a hose reel in the front and rear and a regulator setup for painting and feeding my oil burner during the winter. PVC is a good way to get hurt.
I ran my whole shop in PVC and for 5 years I fought leak after leak and breaks that did literally explode.
None of the breaks killed me, I was right there for several breaks and got a nasty cut or two at worse.
The last straw was getting to a point where I had to fix big leaks every week. I spent a couple hundred on copper and redid the whole mess. Now no leaks and no worries.
I still shut the air off at the compressor every night and for that reason I sometimes miss all those leaks. It used to be the loud hissing noise would remind me I needed to turn off the valve at night. It's harder to remember now, but I can hear the radio better!
hawk you said the law states nothing over 100psi and in properly sheilded condoit or under ground.
Max is saying 90 psi (10 below what the law regul;attes it to).
and designing would mean buriing it or wrapping it in realy strong condoit. if given the chioce i'm going with steel or copper. but in a pinch i will use pvc iether burried or wrapped in realy strong condoit.
"It is better to keep your mouth shut and appear stupid than to open it and remove all doubt." - Mark Twain
'70 f250 4x4 Crew cab 460/C6 '72 F100 390/C6 9.8 MPG AVG. '89 Mercury Cougar LS Dual Exh. V6 . 18.9 MPG AVG. In Town.
I don't want to give em a heart-attack. That is what would happen if I answered the door in the buff. Heck it almost scares me to death when I step out of the shower and look in the mirror.~Mancar1~
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