Since I am getting close to adding air in the new Dust Bowl Speed Shop World headquarters, I figured I would start researching this. I was looking at that ridiculously priced kits from folks like Eastwood etc. and I figured they didn't tool up to build that specificaly for air lines, so it had to have an original source. I started looking into PEX and I found a tubing called PEX-AL. It is standard pex with an aluminum liner. I think this must be what they are using. It's WAY CHEAPER to buy it in bulk. I am thinking of plumbing the entire shop in either 1" or 3/4" . My question is this...since I have to bottleneck down to a high flow fitting (which is a true 1/2"), is the extra cost incurred for the larger diameter a waste of time? I get the fact that I will have extra volume, acting as sort of a reservoir, but 3/4" is cheaper than 1" etc. I will build a "halo" system that encircles the entire shop having drops occasionally for outlets and drains. I want to install a drier/refrigerant type cooler inline, but how would that work in ahalo system or would it? What say ye?
You might talk to Sid about this. He plumbed his axle shop with just regular PEX and that was likely almost 20 years ago now. Pretty sure he learned some things and had good luck overall with his setup.
My limited research says that pex is a bad option for an air line as it can fail catastrophically under air pressure. The piping in the kits I've seen are specifically rated for air. Because I'm a gas fitter from way back and I hung on to my 1/2 through 1" hand dies when i retired I went with black iron pipe. I found the costs were reasonable for my setup. YMMV Phil
Really? Not sure how it would be catastrophic....PVC, yes. It shatters. This has an aluminum inner liner in between the pex. I do a lot of paint work and I don't want any contaminants in my line. Plus I am getting ready to invest in professional grade powder coating equipment, so I need to ensure that it is as oil free as possible. I used 1/2" Zinc pipe in my old shop, but I need roughly 500' of line, so I am afraid pipe is out. I guarantee that, no one did the research and development for a small market like air supply for garages. It had an industrial application first. It wouldn't be cost effective to tool up for such a small niche market. Pex is sensitive to UV degradation, but it should never be in direct sunlight. Not trying to sound argumentative, I just tend to over research. Here are the specs on it, just from a quick Google search. Nominal Size Outside Diameter (OD) Inside Diameter (ID) Minimum Wall Thickness 3/8" ~0.472" ~0.346" ~0.063" 1/2" ~0.630" ~0.500" ~0.065" 5/8" ~0.787" ~0.637" ~0.075" 3/4" ~0.984" ~0.806" ~0.089" 1" ~1.260" ~1.024" ~0.114" Benefits Oxygen Barrier: Aluminum prevents oxygen diffusion, protecting system components. Memory: Holds its shape after bending. Durability: Resistant to corrosion and chemicals. Pressure ratings and pressure testing PEX-AL-PEX Pressure Ratings Pressure testing - Hydronic & Radiant Heating Systems 200 psi @73°F 160 psi @140°F 125 psi @ 180°F Let’s keep the discussion going…..
Catastrophic might have been too dramatic. In the specifications you listed there is no rating for air. If something bursts with air in it it's a instant release of a lot of energy, that's not the same with water. That's why pressure vessels are hydrostaticly tested. All that being said I haven't found any reports of major incidents using pex as an air line. As you say the aluminum lining would make a difference. Phil
Phil, What’s funny is they recommend all testing to be done with air. I just left that part of the text out, due to all the other boring info I had already listed. I’m not too concerned about failure. I’m more worried about the overall design. I just don’t want to have to go back and rework it later.
I'll be posting it in this thread. https://www.jalopyjournal.com/forum/threads/dust-bowl-speed-shop-world-headquarters.1306720/
This link is for Badgerpipe. https://www.amazon.com/dp/B07C55FCTB/?tag=atomicindus08-20 It shows lower pressure ratings. Still 160 PSI, though. Looks just like the pipe in the kits for sale. Gotta think there is probably some redundancy built in. I would guess this tubing would see 200 PSI easy enough. My compressor peaks at 175.
How much astatic electricity does PEX generate when air p***es through it? I used 1/2' galvanized and grounded it for that reason,
Another mention of using copper. Maybe a smaller system then you are planning but my results have been excellent for many years now. I have a (built in 1984) 5HP 2 stage cast iron compressor with an 80 gal. tank. Suits my air capacity requirements. The compressor is located on the north side, outside of the garage in a shaded, separate sound proofed/insulated enclosure. Cool air, is power vented out from the inside of the climate controlled garage into the enclosure to help keep it running cooler. A flexable heavy 1" rubber air hose connects through the wall, to a cooling tower I built from 3/4" type L copper pipe inside the garage . The 3/4" copper cooling tower has 4 upright legs that collect every drop of moisture as the air condensates. There are 4 individual drain valves and 1 master valve. This absolutely dry air then splits into 2 separate systems. One used only for sandblasting and painting and the other for general use, both using a variety of desicant driers, filters, regulators, etc. If I recall correctly, it only took the better part of a day to complete the whole system. Just an easy way to get the dry, clean air that is crucial for blasting and painting. Depending on your needs, you can mix and match piping materials for individual purposes and add as many drops as needed. The copper is simply the best for moisture removal without using a refridgerated system. Its an interesting topic that I have dabbled in my whole life both professionally and as a hobbiest. Good luck with this phase of your garage design!
Good question. I have no idea. I'll have to research that. I burried copper rods in the concrete in multiple location. I have the building grounded to it. I planned ahead since I am planning on opening a powder coating business.
That's super cool, but it would bankrupt me. I have a rough estimate of 500' so far. I'll post a pic of my drawings when I finish.
I’m going through the same process, plumbing air in my home shop. After a lot of research, I am using 1” PEX. I was careful to choose a pressure rating (PN12.5) that was higher than my compressor relief valve setting - no more burst risk than low pressure rated copper tube. I have saddle-clamped it every 3’ so that if a fitting lets go the pipe will not whip. No need for an aluminium liner, as no contamination from the PEX. It was easier to run than the copper that I replaced (I put that it 20 years ago), and one third the price. Lots of fittings available, including poly-to-threaded (local market uses BSP, suspect your threads may be NPT locally). You can run a high-zoot filter/drier on a halo main - just plumb it between the compressor and the halo. cheers, Harv
Honestly, I am OCD, so the aluminum is more for keeping it's shape rather than trying to curl up like standard pex. It's just a little more. I am still not 100% on the PEX-AL, becuase of the specialized compression fittings required. Standard pex would be a lot cheaper.
I found the same - PEX-AL tubing was cheap per foot, but the fittings are spe******ed so all-up about the same as copper. PEX was about one third the cost of copper. I waited for a warm day, then unrolled the PEX and clamped it as I laid it down. Came out pretty straight. A heat gun (or gentle propane torch) would probably get it near-perfect. cheers, Harv
My shop was plumbed in 3/4” black iron when I acquired it, there were three drops, but it terminated about half way from the compressor to the back room, a 24x32’ addition added later, where I installed the 2 post lift. I just used rubber air hoses to reach the back of the shop, where I do most of the work, but finally got tired of tripping over the air lines. I have most of a roll of 3/4” barrier pex left over from when I did the staple up radiant in the house that I was all set to use, but after a little poking around found a 100’ PEX / al kit on Amazon for only $69, complete with three drops and terminating outlets. For that price it was a no brainer. i ended up buying a couple more fittings, and they really weren’t that expensive. The system looks exactly like the more expensive RapidAir system in every detail. Just less expensive. It went together seamlessly, although I did splurge and buy a tubing straightener since it works on 3/16” brake tubing also. There’s a lot of noise badmouthing these kits, but from what I can tell it’s all “I heard that” rather than from first hand experience. By the way, most call it Pex/Al, but from my research, it’s actually HPTE or something like that. You sometimes have to dig deep into the specifications to find that. I bought mine last spring and when I checked in the late fall, my kit price had jumped to $94, which is still a bargain. No scrounging for fittings or cobbling terminal blocks. It even includes Chinese gloves, wall clamps, a tubing cutter, and Teflon tape. The Milton air fittings are about all I had to add. It went up easily and no leaks. My existing black pipe has leaks in a couple of places that are out of reach ( for me) near the 16’ high ceiling. Now, what do I do with that leftover pex?
I am leaning towards 3/4 standard pex right now. I have time to make my decision. I tend to over-research.
The problem with using plastic lines is heat. I have seen temperatures at the tank of my compressor at 200+ degrees. A buddy of mine says black steel pie is the best. Galvanized has a tendency to flake off into the air. He’s a tech for Ingersol Rand.
Black steel pipe comes coated in a preservative oil. That's a no go doing paint work. My compressor has a chiller and I will have a refrigeration/drier unit inline as well. Temps won't be an issue. Most pex is rated up to 200*.
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