I know the shop airline question has been asked more than enough times. I allready know i am going to use copper tubeing . So if i understand right, the bigger the tube, the better the air volume will be. But what i want to know. For my little shop (2 car garage) will going to the 3/4" lines make that much of a differance? all I will be doing is running from one side of the shop to the other. Also, if it makes a difference, i will be running a sandblast cabinet about 20 feet from the compressor.
With the price of copper I would look to aternatives--steel,plastic. I see a lot of commercial shops run in pvc.
If a commercial shop has PVC compressed air lines, they are in violation of the Building Code and the installation probably was NOT done under a building permit. It is dangerous to use PVC for compressed gas service as the PVC is susceptible to catostrophic failure with sharp pipe fragments flying about. PVC is not rated for compressed gas service and WILL fail from sharp pressure spikes in the line. DO NOT EVER USE PVC FOR COMPRESSED AIR LINES!!! This topic comes up frequently and will always get this same answer. Don't be stupid and use PVC for compressed air. Safe working places are VERY important. Remember your wife and loved ones want you to come out of the garage as one, complete functioning person.
One thought to keep in mind is that it takes about 50 feet for moisture to condense and settle out of lines. For this reason you might want to build a grid next to the compressor of line to build in this distance in order to reduce moisture getting to your tools. Also when you install the drops make the "T" for the drop come off the top of the main line because this will also help keep water out of the drop. The media in that blast cabinet definitely won't like moist air. Larry OKC
Brianangus in Canadia can explain better but volume and pressure are inversely proportional. Therefore Pressure increases with smaller pipe and decreases with larger pipe. Since air is obviously compressible, there will be some change in pressure with longer pipe run but maybe insignificant as he stated. A pressure gauge at both ends will indicate any difference. To meet the needs of the sandblaster, I have plumbed in an extra tank for volume storage. You may have a mega monster compressor so don't need it. I am not an expert about pressure ratings of copper and copper fittings, but I only use steel pipe.
Without going into a lot of Blah--blah--blah---If you have a 2 bay garage and a 5 to 8 HP compressor, then you will never see the difference in 1/2" diameter copper lines and 3/4" copper lines.
Exactly; at 10 cfm flow rate, a 1/2" line will lose 0.6 psi in a 100' run; in a 3/4" line it will lose less than 0.1 psi. The bigger line would help cool the air (more surface area), but on high usage like a blast cabinet you really need an actual cooler or dessicant drier, especially that close to the compressor. Ditto on the PVC, AZAV8! Black pipe shouldn't be used, it corrodes and will damage tools; use hot dip galvanized if you want iron, but copper is good to pressures beyond normal hobbyist shop compressors.
DO NOT EVER USE PVC FOR COMPRESSED AIR LINES!!! This topic comes up frequently and will always get this same answer. Don't be stupid and use PVC for compressed air. Safe working places are VERY important. Remember your wife and loved ones want you to come out of the garage as one, complete functioning person.[/quote] Our man is right!!! My PVC setup was a BIG mistake. I went out to fire up the garage - heat and compressor - ya know, winter in Michigan. Too cold to wait for it all to come up to temp, so went in for coffee. While in the house I heard the blast in the detached garage. Glad I came in. Looked like a PVC gernade went off in there. I KNOW I WOULD HAVE BEEN HURT. Anything but PVC...
Dustyoldbodyman's story sounds like mine. I had cranked up the compressor to fill the tire on my lawn tractor, and heard a noisefollowed by the sound of rushing air. That's right the PCV pipe exploded. It had been in the garage about 10 years. Even with the rising cost of copper pipe I replumbed the garage with 1/2" copper pipe. The PCV pipe was cheap and easy, but for safety either black pipe or copper pipe.
Interesting. Are we talking about the same PVC? I have about 80 ft of 1 inch pvc in my (home) shop, some schedule 40 rated at 450 psi and some thinwall rated at 200 psi. My compressor only has 120 psi Max. It was some PVC pipe I had laying around and I purposely checked the rating before I used it.
thanks For the info to some of you guys. And to all the guys preaching about pvc and black pipe, READ the second sentance in my original post. THANKS.
Just a comment... You can run 3/4" lines, but you'll still have the restriction of 3/8" at largest, probably 1/4" at regulator, dryer, filter so the only thing larger lines do for you, essentially, is give you more overall volume. If you need more than 80 gallons of volume, I'd suggest another, bigger compressor. I used black pipe, and it cost $100 + just for about 30 foot of pipe at 1/2".
Anywhere the PVC turns "90's ,tee's, ECt " it will overheat at the point that it turns. Each time it overheats it will make the Pvc a little more brittle. Now if you have a straight line you may be able to use it forever.
We've had PVC in the shop where I work. Water cannot be compressed like air. That's why PVC blows apart like a grenade. Ours usually explodes at the tee's or elbows. Today they said we're going to plump in metal lines.
I just did mine over the weekend w/copper pipe and the crimp type fittings, no soldering (except for the valves). Worked great, and no heat, mess, etc. Not sure if anyone rents the big ass tool you need to crimp the fittings, but it's worth the effort it if you can find one.
The bigger diam. of the pipe cuts down on the friction of the air passing and reduces the heat. The main benifit is less moisure. Copper is also a better condutor of heat so it will reduce moisure as well. I was having problems pumping water while I was painting, my paint jobber had me replumb my compressor with 3/4 copper and no more water. He also said I needed a minimum of 20' from compressor to watertrap, I ran 50'. Buying the copper hurt the wallet but was well worth it.
My PDV was sdchedule 40, and like has been said ately broke near a 90 degre elbow. Don't use PCV pipe for any reason.
Go ahead and use PVC it wont hurt you, If you really have to argue the point of pvc vs other material, just think of it as God way of weeding out the stupid
Not once in this entire thread did i say i was going to use PVC. I agree that you would have to be either be desperate or realy stupid to use it. ALSO MY QUSETION HAS NOTHING TO DO WITH PCV BEING USED. I was asking about about copper tubeing and only copper tubeing.
Another problem with PVC, it degrades from the oil in the lines. This thread should have all the answers to your questions... http://www.jalopyjournal.com/forum/showthread.php?t=51146&highlight=compressor Copper was the cheapest and fastest to run.
I know the question has been answered, but instead of copper or black iron; PEX pipe would be another option, its what I used in my shop. As I am a plumber and have the tools. it was very cheap. 25 cents a foot, and you can buy it from home depot, etc. and rent the tools. Doesn't corrode, smooth wall, and easy to work with. and NO PVC and PEX are NOT the same material, not even close
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