Author	[Modern View]
Brad Buchanan 10-02-2012 14:57:06 74.71.185.165 Report to Moderator	hello all! I am reaching the point that I have to decide what I will use for the air supply lines in the shop. Most of the runs will be horizontal along a poured concrete wall app. 150 foot. I want to run 3/4" pipe. The air will be used for general shop use and occasionally painting. I looked at and priced pex, black iron, schedule 40 pvc and copper. pex, iron and copper were in the same ballpark in price (counting fittings) and pvc was about a third of the others. Advice, opinion or thoughts would be appreciated. Brad [Reply]   [No Email]
Pops1532 10-07-2012 06:45:53 98.227.131.18 Report to Moderator	Re: Compressed air supply line in reply to Dick2, 10-02-2012 14:57:06   Quoting Removed, click Modern View to see Exactly! Ever had an oxygen tank tested? They call it a hydro test... [Reply]  [No Email]
John B. 10-06-2012 14:42:40 38.114.64.195 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   I didn't think anyone ran PVC for air lines any more. I was told the compressor oil would weaken the pipe and fittings. Besides if something would hit the PVC pipe it could be like a grenade going off in front of you. Yes as one person stated put a drain on every air drop. I put an air tank from a trailer in the middle of my run and at the end. This way I was able to use smaller pipe. These small tanks serve as resevoirs and can feed the machines or lines without having to go thru the whole system with less resistance or psi drop. Once you stop using the air these tanks fill back up quickly. Tire machines have always had tanks underneath them. This allowed a large volume of air to be expelled at one time to seat the beads on a tire faster than it could escape from the tire itself. Aring up a tire and trying to seat the beads with just a hose is usually 99% of the time impossible. [Reply]  [No Email]
MisterT 10-06-2012 14:20:17 67.55.162.174 Report to Moderator	Re: Compressed air supply line in reply to JMOR, 10-02-2012 14:57:06   Air brake systems on trucks use some kind of plastic lines, and those don't burst or deteriorate, even when exposed to weather, and road salt, etc. [Reply]  [No Email]
Pops1532 10-06-2012 09:01:09 98.227.131.18 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   If PVC fails when it has liquid in it the liquid just runs out, or sprays out if it's under pressure. The difference between liquid and air, is you cannot compress a liquid. When PVC fails with a compressed gas (such as air) the gas EXPANDS as it escapes. This is what causes the high speed shrapnel that can injure or kill people. [Reply]  [No Email]
Dusty MI 10-06-2012 10:38:24 76.247.153.8 Report to Moderator	Re: Compressed air supply line in reply to Pops1532, 10-06-2012 09:01:09   When pressure tanks are pressure tested they are tested with water NOT air. Just for that reason. [Reply]  [No Email]
MisterT 10-05-2012 07:20:16 67.55.162.174 Report to Moderator	Re: Compressed air supply line in reply to JDseller, 10-02-2012 14:57:06   Quoting Removed, click Modern View to see So you're saying the PVC plumbing in my house could just suddenly disintegrate? Yes, I've known those 5 quart plastic ice cream busckets to get brittle and just fall apart. I've seen plastic milk jugs do the same thing, but those are made of an entirely different kind of plastic than what PVC is made. [Reply]  [No Email]
hd6gtom 10-05-2012 07:19:36 75.170.234.1 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   Brad We built a new tire shop about 6 years ago. The only thing we were allowed to use for air lines was black pipe. It is run close to the top of the wall. Every place we ran a drop for a tire machine has a drain on the bottom. every place we ran a drop for a air hose has a drain . Both air compressors were drained daily. We ran 1" pipe and used 3/4" for the drops. Might have been overkill but when running 2 of our 1" air guns doing truck tires, we never ran out of air. We were told PVC was not legal to install as air line. [Reply]  [No Email]
Puddles 10-03-2012 16:24:09 24.113.77.208 Report to Moderator	Re: Compressed air supply line in reply to MarkB_MI, 10-02-2012 14:57:06   I think this is an updated version of what I have. http://motorguard.com/air_2_5.html [Reply]  [No Email]
Puddles 10-03-2012 13:12:58 24.113.77.208 Report to Moderator	Re: Compressed air supply line in reply to d beatty, 10-02-2012 14:57:06   Brad for the cost difference between copper, and galvanized or black pipe you could buy a Motor Guard system like this to protect your tools, paint gun, plasma, etc, etc. Down side is you can only let 125-PSI into this filter system. But you need some type of filter anyway! :wink: [URL=http://imageshack.us/photo/my-images/163/motorguardsystem.jpg/][/URL] [Reply]  [No Email]
Brad Buchanan 10-03-2012 16:16:58 74.71.185.165 Report to Moderator	Re: Compressed air supply line in reply to Puddles, 10-03-2012 13:12:58   That looks interesting. Did you put the components together or did it come as a kit. By the way, what are the components? Brad [Reply]  [No Email]
Brad Buchanan 10-03-2012 12:11:48 74.71.185.165 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   Amazing the amount of information and opinion on the subject of compressed air piping. I came across this article whitch is a bit technical but seems to explore most all of the possible options. The new flexible aluminum piping looks real slick but the fittings are very expensive and it seems the mfg. only warrantys it for one year. PVC is out. Black iron and galvanized are real good however corrosion and flaking galv. are issues with that. It seems that PEX is not really suited for this application due to sagging on straight runs and not being rigid for outlets and accessories. Can't afford stainless. Right now it looks like copper is the most attractive option. Brad Compressed air article [Reply]  [No Email]
George G 10-03-2012 09:04:08 205.188.116.142 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   The thing about posting on forums. You have to figure out which is BS and which is not. This is what I know to be fact. No air compresser company is going to recommend using PVC or Galvanized pipe. Their are types of plastic pipe that are OK to use, PVC is not one of them. The pressure rating for PVC is for liquid, not for a compressed gas. As far as Galvanized goes. The galvanizing will flake off, and start pluging things up. If someone has a link that says otherwise. Feel free to post it. Piping [Reply]  [No Email]
John B. 10-06-2012 14:33:36 38.114.64.195 Report to Moderator	Re: Compressed air supply line in reply to George G, 10-03-2012 09:04:08   Isn't psi the same wether it's liquid or vapor?? I didn't know there is a difference. Pressure is pressure. The only differenc between the two are; Once a liquid pressure vessel cracks the psi is immediately "0" psi since a liquid is non-compressable, but a compressed vapor vessel will keep expanding and explode to equal the pressure on the inside to what is on the outside. [Reply]  [No Email]
Dean Olson 10-03-2012 07:21:53 98.196.66.64 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   Galvanized or copper in my opinion as a Master plumber who piped miles of compressed air lines. Black will work fine but seems to create a lot of rust and debris as it ages and the moisture in the air corrodes it. Most of the new systems, specifically designed for air, available today are pretty expensive and not easy to find parts. Read that as your not going to run down to the local hardware on Sat afternoon to get parts for repairs or additions. The other problem with "new" technology is it may not gain popularity and become obsolete. To those that have used PVC pipe for compressed air and argue that "I haven't had a problem yet". That doesn't make it make sense. As a young and dumb kid I used to run sleds in the winter and dirt bikes in the summer at high speed, WOT all the time. I had a 79 Honda Goldwing in excess of 110 mph on IA gravel roads. I had a Yamaha GP433 racing sled that would run 80 mph. " I did that all the time and haven't had a problem yet" It took a buddy losing his life for me to stop that crap. [Reply]  [No Email]
Puddles 10-03-2012 06:29:09 24.113.77.208 Report to Moderator	Re: Compressed air supply line in reply to Fawteen, 10-02-2012 14:57:06   Stephen Newell if you have over three employees I wouldn't want to be you if you have an accident. OSHA has a little thing called competent person. They can make your life miserable! http://www.osha.gov/SLTC/competentperson/index.html [Reply]  [No Email]
MisterT 10-03-2012 06:17:45 67.55.162.174 Report to Moderator	Re: Compressed air supply line in reply to dave2, 10-02-2012 14:57:06   Quoting Removed, click Modern View to see Finally, someone with actual experience and knowledge has spoken up and stated the honest, real facts. [Reply]  [No Email]
MarkB_MI 10-03-2012 08:53:07 198.208.251.23 Report to Moderator	Re: Compressed air supply line in reply to MisterT, 10-03-2012 06:17:45   >Finally, someone with actual experience and knowledge has spoken up and stated the honest, real facts. Mr. T, I don't know whose post is more irresponsible, Steven N's or your post in support. The real "facts": PVC pipe is not approved by OSHA or anyone else for compressed air. Here's directly from OSHA: "Since PVC material does not possess shatter resistant property, and since it is very clear from the industry's recognized practice that PVC pipes are prohibited for above ground transportation of compressed air and gases (unless the pipelines are encased in shatter resistant material), any such use by the employers, where employees may be exposed to hazards, will be in violation of Section 5(a)(1) of the OSH Act. Therefore, employers who are found to violate the above described conditions or manufacturer's recommendations, during an OSHA inspection, shall be issued a 5(a)(1) citation." Just because thousands of cheapskates use PVC pipe for compressed air and get away with it doesn't make it a good idea. OSHA on PVC pipe for compressed air [Reply]  [No Email]
Stephen Newell 10-03-2012 04:25:23 66.53.82.103 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   I'm a professional cabinetmaker and furniture refinisher. I've been around PVC for compressed air on a daily basis for 40 years and I've never seen any of it fail on its own. If you adapt to black or galvanized pipe where the couplers attach, it can be securely be fastened to the building and you won't have a problem. I have worked for others that have secured the coupling ends to a post with duct tape and have someone pull too hard on a air hose and break it. It makes a lot of noise but it isn't violent. 3/4" schedule 40 PVC is rated for 289 psi. As long as keep the pressure at a reasonable limit and the pipe is not hit and broken it will handle the air from a compressor. I keep mine running up by the ceiling where its been since 1986. [Reply]  [No Email]
Ken Macfarlane 10-03-2012 06:14:38 184.151.127.230 Report to Moderator	Re: Compressed air supply line in reply to Stephen Newell, 10-03-2012 04:25:23   Don't listen to this poster, PVC at cold temps is very brittle, the pieces are very hard to extract if they blow up because x-ray translucent. Its only rated fro 289 psi on water not compressed gases! Yes a break across the threads isn't too exciting, but a longitudinal rupture is bad. Also, PVC can break down over time when exposed to some other plastics, I can't recall if it gets brittle or goes soft but it will fail at lower pressures. No reason to use it for air service. [Reply]  [No Email]
Stephen Newell 10-03-2012 20:44:31 66.53.81.124 Report to Moderator	Re: Compressed air supply line in reply to Ken Macfarlane, 10-03-2012 06:14:38   I guess you believe in man made global warming too. [Reply]  [No Email]
Ken Macfarlane 10-05-2012 06:46:56 184.151.114.121 Report to Moderator	Re: Compressed air supply line in reply to Stephen Newell, 10-03-2012 20:44:31   Global warming ain't got nothing to do with it. I'm guessing just because you've never had one blow you don't believe it will happen. Ever left a rope out in the sun and had it get brittle? Or even just had some plastic container sitting on the shelf inside in the shade a few years that you go to pick up and it falls apart? Happens to PVC too. [Reply]  [No Email]
MarkB_MI 10-03-2012 02:39:09 75.219.11.240 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   Black pipe has been used for many, many years for compressed air. Copper is good too, and would be a good choice if you don't already have dies and cutters for steel pipe. PVC is not approved for compressed air. Lots of people have used it, but that doesn't make it safe. PEX is a better choice, but it also NOT approved. PEX-Al-Pex is a soft aluminum pipe sandwiched between inner and outer layers of PEX; it's approved for compressed gas but costs about the same as copper or steel. There are plastic pipe systems approved for compressed air; if you're insistent on using plastic go with one that's approved. Otherwise stick with black pipe or copper. [Reply]  [No Email]
Puddles 10-03-2012 02:23:08 24.113.77.208 Report to Moderator	Re: Compressed air supply line in reply to motorcraftman, 10-02-2012 14:57:06   Brad my compressor is 175-PSI too. As someone already mentioned the pipe is rated at 160-PSI, which I believe is true, but at what safety factor. 3 to 1, 5 to 1? Pay close attention to a lot of pictures of guys tractors, a lot of their hydraulic lines are plumbed with regular old black iron pipe! In fact I have some on the out riggers of my backhoe. :oops: http://www.osha.gov/dts/hib/hib_data/hib19880520.html [Reply]  [No Email]
Brad Buchanan 10-02-2012 21:14:26 74.71.185.165 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   What a great response! I found the replies extremely helpful and they helped me know the issues and do the proper research. I forgot to add two more factors: Needs a working pressure of 175psi and am shooting for a 20+ year durability. Brad [Reply]  [No Email]
old_bc 10-02-2012 21:01:02 72.161.184.32 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   Do not use schedule 40 plastic for air pipe. The biggest problem is that the glue is incompatible with the synthetic compressor oils. I am speaking from experience. [Reply]  [No Email]
algar 10-02-2012 19:41:37 74.212.60.71 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   Proctor and gamnble uses soldered copper and SS for mains no rust particles [Reply]  [No Email]
Smart arse guy 10-02-2012 18:58:16 66.188.56.202 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   Just use Schedule 40 PVC for all lines and fittings. Whats the worst that can happen? [Reply]  [No Email]
David G 10-02-2012 19:05:41 205.215.206.18 Report to Moderator	Re: Compressed air supply line in reply to Smart arse guy, 10-02-2012 18:58:16   Death [Reply]  [No Email]
David G 10-02-2012 18:42:38 205.215.206.18 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   PVC is not recommended, and actually discouraged for compressible gasses. I will not get into more discussion than that. [Reply]  [No Email]
Flex. Aluminum..John,PA 10-02-2012 18:35:22 209.163.118.69 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   Recently I visited a supply house where they specialize in air compressors and air delivery systems for commercial and industrial installations. They now have a new (to me, at least) a flexible ALUMINUM pipeing system. Color of the pipe is blue. All connectors are "push-on" type. 1/2 in. and 3/4 in. The pipe is not PEX. So, you might look around your area for such a supply house and ask about the new stuff. I do not recommend using PVC. As the PVC gets some age, it seems to lose flixibility and will shatter, instead of bending or simply cracking. If in doubt, remove a piece of "aged" PVC and do a sample bending of the pipe. Becareful of flying debris. Only problem with black pipe might be the collection of moisture and rust inside the pipe. Water drains should be installed according to the Codes. Hope this helps. John,PA PS: Like all new products, I will wait awhile and see how that new flexible aluminum holds up. Meantime my rubber hose system will work for me. [Reply]  [No Email]
Charles (in GA) 10-02-2012 18:33:25 24.181.68.143 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   If you really want to start a long ugly, nasty thread just say you plumbed your shop with PVC and it has lasted for years and its OK.......... Google PVC air plumbing or similar....... PVC is not designed or approved for compressed air and will shatter under pressure and send lots of plastic flying everywhere. Other materials will simply rupture, but not shatter. Its been an OSHA violation since about 1988 in commercial use. Charles [Reply]  [No Email]
Ken-Pa 10-02-2012 15:22:29 75.179.43.1 Report to Moderator	Re: Compressed air supply line in reply to Brad Buchanan, 10-02-2012 14:57:06   Several years ago , I worked general maintenance for a large Auto/truck parts & supply store . He also sold all types autobody shop equipment & supplies . He set me up as air compressor installer & maintenance plus occassionaly if the customer wanted to do his own installation , my job was to go to that particular body shop or garge to give the guy instructions & ideas for piping & safety. All compressor companies we dealt with at that time demanded 3/4" Galvanized pipe & fittings , with an inline drain valve for draining water buildup . Black pipe is for gas & is dangerous for compressed air usage . If other than Galv pipe was installed , the company voided the warranty on the compressor . HTH ! God bless, Ken [Reply]  [No Email]
Ken Macfarlane 10-02-2012 17:55:00 184.151.114.61 Report to Moderator	Re: Compressed air supply line in reply to Ken-Pa, 10-02-2012 15:22:29   Only issue I know of with plain steel pipe is corrosion. Have to keep and eye on it and have filters if painting. I had 3/4 copper in the last shop, liked it alot. New shop hasn't been hard plumbed yet. Planning on either transport air line (pex) or conventional pex with a starter piece of copper for cooling. [Reply]  [No Email]
DH in Carolina 10-02-2012 16:03:04 173.212.13.142 Report to Moderator	Re: Compressed air supply line in reply to Ken-Pa, 10-02-2012 15:22:29   Schedule 40 black and schedule 40 galvanised pipe both are rated for 150 lbs working pressure. Black pipe with malable fittings is fine for air line. My Quincy compresser is factory piped to the tank with black pipe. [Reply]  [No Email]
Puddles 10-02-2012 15:09:02 24.113.77.208 Report to Moderator	Re: Compressed air supply line in reply to Andy C, 10-02-2012 14:57:06   Don't use PVC! Numerous horror stories on the net about using it. I used galvanized pipe in my shop, 12-years now with no problems. [Reply]  [No Email]
wvajim 10-02-2012 16:55:04 173.80.241.17 Report to Moderator	Re: Compressed air supply line in reply to Puddles, 10-02-2012 15:09:02   Might take a look at this: Rapidair [Reply]  [No Email]