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new air compressor, what size hard lines to run?

All compressors have a popoff valve for safety if the electric pressure/shutoff mal functions just like any pressure vessel as in water heater etc. and keeps things from exploding. Air comp explosions are catastrophic, or maybe I've just seen to much mayhem in my days and a little extra safety is always good. And also let your horizontal longer runs go down hill so water and crud can fall in the driplegs at the end of your runs.
 
yes, that I knew. I never realized those blow off pressure relief valves had a term for them. lol
 
I think you will find 1/2" size will suffice and will be cheaper also as it is used far more than smaller sizes. You might consider PEX for system lines-it is available in straight 20 lengths.You should also take your branches off the top of the mains to avoid water draining down them. As was said earlier, pitch the mains down to a bottom take off branch for drainage. A complete loop around the shop is a good idea also and ball valves ahead of stations and quick connects will make service much easier. I always feel vulnerable when I have the air system off line!
Mike
 
Pipe O.D. is all the same, its the inside diameter that changes. Referred to as schedule. I believe standard wall thickness is schedule 40. Pipe schedule used is determined by pressure and temperature for any particular application.
 
Pipe O.D. is all the same, its the inside diameter that changes. Referred to as schedule. I believe standard wall thickness is schedule 40. Pipe schedule used is determined by pressure and temperature for any particular application.
"Wrong." All outside pipe sizes are not thee same. Think I`d run a few feet of 3/4 to the first opening or two, then 1/2" for the rest, depending on how many openings, then ur 1/4" hook ups. Of course, I don`t know much, I only did that crap for over 45 yrs.
 
Just a couple of things here I read here....
The size of your tank, is not how to size your compressor, cfm and horse power is. The size of the tank 40, 60.or 100, will not dictate anything but recycle time. A minimum 5 hp for home use, and not one of those home depot 3.5 to 5 hp models....(junk)... If you are working alone, impact gun or ratchet, one of those cheeseball compressors will suffice, however, if you are sand blasting, or doing bodywork, you will notice in a couple of minutes or so, how under powered you are.Two people, two orbital sanders, and you will know what I'm talking about, Ok for the hobby guy, if you are depending on it for income, do not sell yourself short, spend the money...

As for piping, 1/2 on drops and feeds only 1 inch or 3/4 for main lines, slopped back to the compressor. not too individual end drain caps. They sell automatic timed compressor drain systems for a reason. Running your lines down with an inverted traps will keep most condensate water in the mains.

Do not use plastic, or pex. Ridgid piping, copper, (expensive) or preferably black iron. No sags, no entrapment of water.
 
"Wrong." All outside pipe sizes are not thee same. Think I`d run a few feet of 3/4 to the first opening or two, then 1/2" for the rest, depending on how many openings, then ur 1/4" hook ups. Of course, I don`t know much, I only did that crap for over 45 yrs.
Bob i could be wrong as pipe over a certain size may be different OD. However are you thinking of tube? When we ran out of Schedule 80 or extra heavy i at times used tube which was used for Boiler water wall or superheaters. Say i needed a piece of two inch and i didn't have it, i took tube and turned down the end, usually only a small bit to get it to fit a socket or line up with a butt weld. Again OD is the same on pipe with the ID that changes as far as my experience.............BTW in my pipe fitters manual all pipe OD is listed the same, just my experience
 
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I piped my garage like this. Main line mounted high up and tilted toward compressor. A tee pointed up elbows to a pipe to bring it to work level a tee for air fitting and below that a valve to drain any water. Think I saw this design in Old Car weekly .
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I have an 80 gallon in my shed. I ran this in the shed and under ground inside of pipe to my garage..
 
Black pipe, galvanized, and brass threaded pipe have an IPS out side diameter, which is the same as Schedule 40 PVC pipe.
Copper tube out side diameter is CTS= 1/2 inch inside diameter is 5/8 inch out side diameter CTS
1/2 inch inside diameter is the same weather it is IPS or CTS out side diameter
CPVC is the same outside diameter as copper tubing
I prefer to use galvanized threaded pipe for air lines.
Being a licensed Plumber in New Jersey I have worked on many different jobs using air lines.
Auto repair shops, full serve car washes, concrete block plants.
 
I'm looking to using something similar to what BeepBeep posted only with a 1/2" ID and 5/8" OD. Kit is around $175 and is a polyethylene inner and outer wall with an aluminum core sandwiched in between the polyethylene. No need to worry about rust or corrosion and no need to worry about cutting and making threads onto black or galvanized pipe to get it to hug the wall. Might also be more cost effective than black or galvanized pipe too.
 
“Bigger is always better” in everything but automotive; most of the time!
 
True but when you are trying to keep on a budget, there is no need for an over kill on the size of the line when a 1/2" line is more than suitable for what I'll be doing in my garage at home.
 
Galvanized pipe will not rust inside from compressed air.
I have added to air lines made from galvanized and after 15 years no rust.
L grade copper tube can also be used for air lines and readily available at home center stores.
I have installed it in car washes to run the equipment, no corrosion issue.
I have no experience with polyethylene air lines.
 
Big thing is that my air compressor is outside in a shed that is not heated which is butted up against my outside wall of my heated garage. I know the condensation and moisture in the air inside the lines will in fact start corroding the galvanized pipe eventually once that coating is gone. If it was all inside my garage ( wish I had the space for it in there but I don't ) it wouldn't be a problem due to the garage being heated and all one temp.
 
Again, working on a budget as I have my house to still finish renovating too. Doing everything in copper will be far from cost effective. That is why I have been checking out these polyethylene hybrid kits. They seem to have had good reviews. My dad has the smaller single wall polyethylene 1/2" OD with 3/8" ID in his heated garage and has had no problems.
 
Sounds like you have your answer.
Copper is not as expensive as everyone thinks.
Good luck with your project.
 
It definitely adds up with having to reroute some plumbing in my house with redoing my kitchen and bath rooms however, with my water lines, I prefer to have copper vs the PEX stuff since mice can chew through plastic.
 
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