I need volume. I need 1/2 or bigger lines for my shop. Do they make 3/4 inch air hose? If so where would I buy it? If not is 1/2 inch enough to make a diffrence from 3/8''? Do i need to run hard lines every where? I might have a vibration problem with the hard lines though. thanks
I used 3/4" black pipe to plumb my air lines to the walls of the shop. A flex coupling off the compressor isolates any vibration to the hard lines. Every 10 foot or so, I put in a "T" with a 1/4" FPT bushing and a 1/4" quick disconnect for my 3/8" air hoses. In my old shop, I used 1/2' copper pipe soldered together, with "T"s with 1/4 pipe thread and quick couplings. Bigger pipe means more air volume, and less pressure drop in the system!
how much pressure are you running? and how many cfm (cubic feet per minute) do you want to obtain? we run our air lines out of 3/4in cpvc, available in any building supply store , only put in one flex joint at compressor, it was 12 inches long used regular plumbing straps to fasten pipes to ceiling and out of the way with down lines at 10 foot intervals with quick coupliers on the end. for large volume you need to limit the number of elbows in the line , used large quick couplers and I/2 line to tool. if you install cut off valves be sure to buy ones with ball valve 1/4 turn type handle to avoid restriction. should supply plenty of air but you can always buy or build a pig. pig is a tanks that you set up close to where you are working and plumb air line into it and as many lines out as you want with the size couplers you want presto instant volume for short time .
thanks for the input - I am going to go with the 3/4 inch pipe. what do you use as flex fitting? I need roughly 20 cubic feet per minute. the aircompressors i have now will handle it but the lines are what is making the machine struggle.
note cpvc is cheaper than anything else that I know of ,and will hold up to 200 psi. if you do use cpvc always keep a few extra fittings around and a can of glue, easy repair if you do yank to hard on a line
do a search on this...it's been covered very thoroughly...I remember diagrams on how to run your lines for (mostly) moisture free air...black or galvanized pipe is best, or copper...won't blow up and kill someone and metal pipe cools your air to help remove moisture.
Go have a high pressure hose made at most auto parts stores with I/2 or larger inside diameter , be sure to secure lines well at the end of cpvc and every 6 to 8 foot after, note cpvc wont rust or contaminate your air supply, fitting available every where and cheap. dont need any specialized tools to install antoher note, if you run 3/4cpvc it will be about 1/2 in inside diameter inside run that into a five gallon pig and run 3/8 out . have the pig portable so that you can move it around the 3/8 line should be kept as short as feasible to the working device (tool), this will give you volume and pressure.
I have worked around major shops for more than thirty five years including the airline industry and I have never heard of an air line blowing up and killing any one , the only deaths or injuries i ever heard of were due to disregard of common safety rules. in the airline and automotive industry non conductive type air lines are the rule with good ground straps at every work station to go from a known ground to the work piece( item being sand blasted or sanded, or drilled, or whatever) to eliminate static DISCHARGE.
If moisture is a problem then you need to install sometype of airdrier system. moisture is not a good thing for air tools, or paint jobs, cpvc will not create moisture as will metal pipe , every see what comes out of black pipe that has been hooked to an aircompressor with no air drier, looks like burnt motor oil, really good for paint jobs and air tools.
Be careful with CPVC air lines .I once heard about a guy that had them in his shop that caught fire. The fire melted the lines and the pressure in the lines fanned the fire making it worse.
After the last pvc debate, I actually saw one that had blown apart and damaged a guys 55 Chevy. I will never use the plastic pvc pipe in my shop. I was on the fence but now I am definately not.
I had a cpvc pipe blow apart in a shop I was working in....scared the **** outta me and blew sharp shrapnel all over the place....go ahead and use it...I never will....Black pipe is CHEAP and safe.
if you use pvc it has to be the schedule 40. it's thicker walled than the cheap stuff. easy to repair or add on to
I call ********. I mulled this over with an SME, a car guy here in WA who sells PVC for a living and he would not run it in his shop, he used black pipe. Don't do it, you may hurt yourselves.
i tried researching it. it is supposedly not osha approved. so i would have to agree and say not to use it. i did read there is pvc rated for air use. however it cost's the same as pipe. so the only advantage would be ease of installation. once again i say don't use it.
Plastic gets brittle with age and also "workhardens" from the pressure cycles it sees. Also, its a natural insulator which keeps the air warm as it p***es thru it, thus holding moisture in suspension longer. If your worried about water actually flowing in your pipe and running out your hoses, and not only the moisture thats suspended in the air from formed condensation, you have the system designed wrong anyway. Your drops should be tapped from the TOP of the pipe. Water doesn't flow uphill.
Black pipe is the best...at EVERY T-fitting where you have a hose connection drop a ****** down from that T...it will act as a moisture trap and keep your lines more water free....drain often. Use a filter/drier at the compressor. I, too, have seen plastic pipe (pvc) explode and send s****nel all over the shop...age and an occasion "bump" can do it...be safe. I got the diagrams from www.oldsmobility.com ...there is more info on this site under air compressor...
Use black pipe, lines should all slope down towards the compressor so moisture will drain back to the compressor. "T"'s should point up, supply lines of the main feed need to go up then back down, keeps moisture out of the line, and run some drain traps off of "T"'s pointing down.
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