best material for shop airlines

I'm a plumbing & HVAC contractor & we run air lines for auto shops, paint shops & industrial. We use either black pipe or copper. PVC is a no-no. Mostly black pipe due to costs- as copper is pretty pricey nowdays. We use copper if spec'd.
Problem w/ PVC- it is not approved for above ground installation for water & not approved at all for compressible gasses. Stick it in your hot garage & over time- the plastic becomes brittle & will shatter if struck. You don't want to see what happens when a PVC line shatters w/ 150 psi. The plastic shards are lethal.

Here's an example of a job we did. Pipe on floor is 2" black pipe. All fittings are black (except some of the caps for test only). This is for a large cabinet shop & a conveyor will be installed over the line later for cabinet assembly. You can see the red tape on floor that defines the conveyor.
There's over 2000 feet of pipe here- ceilings are 26 feet high. Tees on floor are 15 feet center to center.

 

So black pipe seems to be the way to go. What size pipe should you use?????

 

how would 3/4 square tube go?

 

Maybe it's not totally right in a lot of peoples minds but I strung my garage with that dark gray schedule 40 PVC lines.
I have separate lines for air and oil lubricated air for the tools.
Probably have strings totalling 100 feet. It's residential not commercial.
I only use it nights and weekends, not a heavy user and I never run the system over 110 psi.
Nothings exploded yet in 6 years.
Am I okay or should I wear a flak jacket?

 

That's the thing, and the risk you never know it could last for another 10 years it could blow up tomorrow.

 

Also a bad idea on fuel lines. I had a piece break off up stream of the fuel filter late last year and got caught in the float valve on the rear AFB. Instant flood...

 

I used copper refrigeration tubing. Look in a McMaster car catalog. It is rated for some pretty good PSI, more than you will ever need. It was alot less than copper pipe. Remember tubing is sized by O.D. and pipe is sized br I.D. Todd

 

No pvc. Shop we moved into had it, stuff was pretty old, started blowin out and blowin LARGE chunks out of our ceiling tiles. ID use copper if on a budget and low psi. Otherwise use steel piping-(black). Eastwood also sells this blue tubing-(cant remember what its called that is pretty good but expensive

 

One more thing, if you have your tees for outlets off the top of the pipe and come down you don't have to worry about water in your tools. In any air system, the mains need to be pitched back to a blow down drain valve anyway, so water in the lines shouldn't be an issue.

Del

 

When i say old, i mean about 5-6 years. It drys out and gets brittle quick. At least from our experience. Others seem to have better luck with it, but haven one blow above your head...itll make your buthole pucker!

 

I just did my in copper, it was cheaper than Garage Pak and it was easier than black pipe. That is for people that do not have access to a pipe threader. I used 3/4 type L copper pipe. And I did not use silver soldier, I used a different soldier. To use sliver soldier you get the cooper pipe to hot which softens the metal. The solider I used is good for 1500 psi, and I'm running 175 psi to the drops. At the drop I'm regulating the pressure down to a 100 psi. And make sure you run the pipe correctly and will make a huge difference in amount of moisture.

 

-Here's how I'm doing my drops off the feed piping:



I can't recall where I got the idea, maybe off a GarageJournal post, but it's working well. I "mass produced" a dozen or so drops (from the upper "tee" down to the outlet tap and drain valve) as complete units, so when it came time to hang them, there was minimal torch-and-solder work while up on the ladder.

The "top tap" keeps the moisture in the upper feed lines, so it can run down to the drip leg- that keeps it out of the tools and the spray guns.

Doc.

 

If it was dark grey, it's probably ABS pipe and not PVC. However, outside of an industrial brand or two that you won't find at the hardware store it's not rated for compressed air, either.

The thing is, you can't predict if or when a compressed air line will rupture.

 

they have PCV all over work for the industrial air system and it concerns me a lot, I would never use it, the other cool thing about copper, is if you have gone through a lot of trouble to make a cool shop, you can polish it really easy with red scotchbrite. little clear and it looks kick ass. if you are going to make the system to last, the small time you spend polishing it, is well worth the effort. It just has a very mechanical look.

 

3/4 " copper . PVC is just dangerous.Copper is easy and you'll never regret it.I have seen PVC lines done by the book explode and blow the windows out of the shop.

 

White PVC is not UV tolerant. Any part of a PVC system that is exposed to direct sun light will fail in short order.

Light gray PVC is UV tolerant. But it is electrical conduit and not rated for pressure.

Stay away from PVC.

Here is the OSHA view: http://www.osha.gov/dts/hib/hib_data/hib19880520.html

Washington State: http://www.lni.wa.gov/Safety/Basics/HazAlerts/902.asp

 

Having been through and seeing the effects of a PVC explosion in a
machine shop I worked at years ago I went with copper when I finally
ran my lines 4 years ago. As others have pointed out the overall price
difference between black pipe and copper was about $100 on a $500
job plus I didn't have to cut and thread pipe. I used a 3/4" rubber
hose between the compressor and hardline,then a jacobs ladder of sorts
running up to the ceiling over 10 feet then back down in a drip leg
and a 3/4" filter and regulator before going back to the ceiling and around
the perimeter with 3/4" copper sloped back toward the compressor for the
first half then sloped the other direction to a drip leg on the far end. My
1/2" taps come off the top same as Docsmachine.
Reading this thread reminded me to check my drains and I just got nearly
a gallon from the compressor tank and a couple ounces from the first
drip leg. All others were dry. I did have some prior experience repairing
radiators 25 yrs. ago that may have helped some but soldering the
joints were really not a big deal. I built it assembly line style for the drops
and then assembled most of it on the ground leaving only 4 or 5 joints to be
soldered in place. No leaks and no problems in 4 years and it still looks good.

 

I own my own small business in which I build and install industrial controls. Just for the record I ran my air system in black pipe, I have a pipe threading machine, because of the recommendations on the HAMB.

One small fab shop I was wiring a machine in had what looked like green coated PVC pipe. I asked the owner of the shop what it was and he said it was air rated PVC piping. It looks like it was assembled like common PVC but then covered by a green jacket and heat shrunk. Any one ever hear of this? He said it was in the building when he moved in some time ago, it's not his building, he's renting the space, and it's run in all the rental units in the building.

 

I own my own small business in which I build and install industrial controls. Just for the record I ran my air system in black pipe, I have a pipe threading machine, because of the recommendations on the HAMB.

One small fab shop I was wiring a machine in had what looked like green coated PVC pipe. I asked the owner of the shop what it was and he said it was air rated PVC piping. It looks like it was assembled like common PVC but then covered by a green jacket and heat shrunk. Any one ever hear of this? He said it was in the building when he moved in some time ago, it's not his building, he's renting the space, and it's run in all the rental units in the building.

 

I used a couple kits from Summit for my addition...1/2 Nylon tubing, assembles easy into fittings with o ring seals..because it was quick..I didn't want to take the time with copper, my bad...BITCH of a time to get the fittings to seal as tubing comes in a roll and gets slightly deformed..Made a tool to expand the tubing about .005 to bring the dia back to Round..Odds are if I shut the air down for a fix somewheres when I put pressure back in the line some of the fittings will leak and you have to wiggle the line to get the o rings to seat..The other day the wife gets me and says there's smoke in the garage and the compressor is running..The line split about 1/4" from a fitting...BEST--Use copper!!! 2nd best, black iron..little hard for weird routes..3rdsies, garage pak [there are other brands] and maybe most expensive..I'm still shooting myself in the foot for not doing copper..

 

When you use silver solder and a torch it does anneal the copper, but it is a far stronger joint than 95/5 solder. We use silver solder for refrigeration because of the high head pressures, 300 lbs.+ and high heat. Schedule 40 PVC pipe is white, schedule 80 PVC is dark grey. CPVC ( which is used more for chemical resistance and higher heat ) is light grey. Black pipe is still the most durable if hit with something (exploding grinder hard wheel, fork of a lift truck...). Ramblur, that a fine looking system!

Del

 

Huh.....

 

I priced out the green pvc pipe that is rated for compressed air and it was more expensive that copper pipe. So it was a no brainier when I went with copper. And copper has that cool factor that no other air lines have.

 

I put mine in copper, not cheap but no problems for 12 years.

 

I replaced the black iron in my shop with the Kaeser blue aluminum system a couple of years ago. It only took a couple of hours to put in a 50' run with 3 drops and two drains. ____________________________
l l l l l_____________
l l l l l l_filter sys.
drain> l l <drain


It is a little pricey. I think it was around $500.
The mounts keep it around 1 1/4" off the wall.
Tubing is around 1" OD. (actually in mm).

 

Disregard the drawing.

 

Wow-that's like what-$50 worth of copper in Alaska?

 

-Actually, as I recall, half a dozen of those assemblies was something like $30.

Doc.

 

I am wondering about that also - would not this do the same thing and be much easier/cheaper?