Est. 1998 — 27 years of woodworking knowledge
air lines
olbuck
Mentioned using PVC from tha compressor & someone wished that was a joke. At's all i ever seen for air lines.
Saw some once where down below the hose quick couppler, 4-6'', was a thang-aw-mo-jig to catch water that builds up, it had a little cut off valve so ya could empty it. I'uz thanking 1'' PVC be all I'd need.
Re: air lines
John K Jordan
So it wasn't a joke. I would personally not use it. In the 70s I worked in an inspection lab where we did pressure testing - I know exactly what compressed air/gas can do. Google can show cases where PVC has exploded sending shrapnel everywhere.
Do the research. Some reading to get started: http://www.hoseandfittingsetc.com/our-blog/bid/94802/what-type-of-pipe-should-i-use-for-my-air-compressor
https://www.osha.gov/dts/hib/hib_data/hib19880520.html
http://forum.woodenboat.com/showthread.php?104099-CVPC-or-PVC-Air-line
That said you can find numerous accounts by people who use PVC and have not yet had it hurt them or their children. And some people have not yet had a wreck in years of texting while driving. Do you feel lucky?
If you want to use plastic pipe instead of metal the RapidAir system has kits: https://www.amazon.com/Rapidair-90500-Master-2-Inch-100-Feet/dp/B0015A11U2 I installed this and 8 outlets in and outside my shop. I use brass and copper air fittings, valves, drains, etc. In my last shop I used blackiron pipe when I put the compressor in a shed. I like working with the plastic tubing better.
JKJ
Re: air lines
Barry Irby
I agree with JKJ. Don't use it.
One thing not mentioned. If you are there when it fails, you may get hurt, if you are not there and you leave your air system on, it will run until you return. It might burn up or cause a fire.
Re: PVC
Mark Mandell - Gone Round In New Jersey
1. As explained to me, PVC under pressure "ages" over time, more so with temperature changes, and will become brittle, fatigue and fail. This can happen with a water line as well, but there is a huge difference between 60-80psi in water as opposed to 100 psi with air. Water can be pressurized but not compressed so it doesn't "store" energy; break a water line and you get a squirt followed by running water. Break a PVC air line and the plastic shatters into shards and the stored energy in the compressed air sends it flying like an air gun (or nail gun, etc.). This is why OSHA prohibits its use in unshielded air line systems.
2. I have personal experience with the effect as a friend used 1" PVC lines in his garage air system. He called me one afternoon to come look at his garage. One of his PVC lines had ruptured and the plastic shrapnel had gone through the sheetrock on the opposite wall, 25 feet away. He said it sounded like a shotgun had gone off. Fortunately, nobody was in the shop when it happened as I have little doubt he or anyone else would not have survived.
He changed all his air lines out with copper. He has little sign on his shop wall with several shards glued to it. Sign says "Dear Death, Na Ha, Ya Missed Me!"
draining condensation
John K Jordan
An oblique view due to the narrow hallway, but on the left in the photo below is the tube and valve I added to catch any condensation that found it's way from the compressor. The line comes through the wall just below the pressure gauge. I've never had more than a few drops of condensation.
In line are a centrifugal water separator and a desiccant dryer, regulator, and shutoff valves to the various runs I plumbed into the shop. I like dry air around wood, for air tools, and for running a plasma cutter.
Barry is correct, an unattended compressor that runs continuously can burn down the shop (and the house, of course, if attached.) Unfortunately this has happened to real people causing real tragedy. My shop is a hobby but one I would hate to have to build again from scratch.
I turn off the power to the compressor when I leave the shop. The switch on the left in the photo is is a disconnect for the 5-hp compressor in the closet behind the wall. I put all the controls outside the closet since I was afraid that I might not manage the air properly if everything was "out of sight, out of mind."
JKJ
Re: PVC
Kneale Brownson
Friend working with 4" Schedule 40 used for delivering compressed air to snowmaking machines had it blow up and injure him.
The other concern is accidentally striking a deteriorated line with some wood you're moving into the shop.
I use copper.
Several Advantages to Copper
Mark Mandell - Gone Round In New Jersey
1. It dents but doesn't blow up.
2. It conducts/dissipates heat and thus operates to cool the air stream that works to condense water and oil vapor out of the compressed airflow. With line drain legs and keeping your storage tank dry you get much drier/cleaner air to use, especially in near continuous duty cycle use.
Re: Several Advantages to Copper
John K Jordan
>>>2. It conducts/dissipates heat and thus operates to cool the air stream that works to condense water and oil vapor out of the compressed airflow. With line drain legs and keeping your storage tank dry you get much drier/cleaner air...
Recommendations I've read are to run copper the first 20' or so from the compressor, the pipe sloped downward so condensate can run downhill and drip into the sump/drain leg. This is before the any dryers. If a centrifugal water trap is too near the compressor much of the hot moist air will pass right through and condense further down the line and perhaps get sprayed onto your project!
JKJ
Dry Air
Mark Mandell - Gone Round In New Jersey
Starts at the compressor tank. This must be kept as free of condensate as possible. I have used (and recommended) an automatic tank drain for many years. Mine, a Wilkinson low-pressure valve, replaces the bottom drain and opens once during each compressor cycle (for a drop of 20 psi) to drain both water and any oil carryover. McMaster has them, Part No. 4919K13, for $90 or so. Once a year I remove it for cleaning and lube.
Re: Dry Air
olbuck
DRY AIR TANK. 18 wheelers airbrake tank have a corded pulled bleed valve, to get rid of water.. Got one on my 5 hp, got a long cord, compressor is in back of a lot of lumber and etc.,. btw, ALL/EVERYTHING is turned off at panel when I leave shop.
Re: Dry Tank
Mark Mandell - Gone Round In New Jersey
It's good that you vent your tank to purge the condensate; lot of people forget to do it and wonder why their tanks rust out and fail. I also did that manually for a while until I found the auto-valve. Now the only thing I have to remember is the once-a-year clean and lube. If we leave the house for more than a few hours I always flip the switch on the compressor so it won't run. Friend who hangs out here lost his entire shop when his compressor's unloader valve stuck forcing the machine to run continually which over-drew his electric service that arced and set the building on fire.
Tooling along at 75 when the 18 next to you vents his tank can scare the snot out of you if you don't know what the noise is. 