[67drake]

I’m going to run air lines throughout my garage fed by my compressor that’s tucked in the corner. I figure this will cut down on the mess and hassle of running hose everywhere when I’m using my air.
So question is- my rubber hoses are 5/8” diameter. I believe the next closest PVC diameter is 3/4”. Any advantage to running 1” PVC. I would think no, as the 5/8” rubber hose would be a bottleneck anyway, correct?

[67drake]

Well heck. I just thought of this. My connectors are the bottleneck. They appear to be 3/16” ID. So would there be any advantage to going larger than 1/2 PVC? Or am I missing something.

[b-man]

I worked in a shop where most all the air lines were either 1/2” or 3/4” PVC. It wasn’t long before they started failing, they were replaced with copper.

With the price of copper being what it is now plumbing your lines with heavy duty rubber line attached to the wall might be the way to go. They did this at my last workplace and it worked well and save them a ton of money.

[fyrffytr1]

When I built my shop in 2000 I ran 3/4" schedule 80 pvc pipe. I do not exceed 100psi on it and it is still there. That being said , do a search for air compressor tubing or lines . It appears that the piping of choice is aluminum.

https://www.google.com/search?client...pressor+tubing

[rwfisher]

The advantage of the larger pipes is obviously the significant increase in volume which will lessen the cycling of the compressor. Most of the pipe systems are 3/4” whereas the high pressure hose systems ar only 1/2”. While a bit more expensive, I go for the quality and safety of one of those systems over PVC pipes. The other advantage with those systems are their simple diy assembly.

[ID67goat]

From what I know, do not use PVC for high pressure air supply!

https://www.garagejournal.com/forum/...ctures.298384/

[hgerhardt]

Originally Posted by b-man

I worked in a shop where most all the air lines were either 1/2” or 3/4” PVC. It wasn’t long before they started failing, they were replaced with copper.

With the price of copper being what it is now plumbing your lines with heavy duty rubber line attached to the wall might be the way to go. They did this at my last workplace and it worked well and save them a ton of money.

I agree with the no PVC for airlines. That stuff is too brittle for compressed air usage and is worse in cold weather.

I just redid the air supply lines in my garage in 1/2" PEX-B tubing (modern residential water piping). It's way more flexible than PVC and the materials are (relatively) cheap. You'll need to get a crimp tool for the proper hose clamps, but Home Depot has everything you need.

[BTCS]

Black or galvanized threaded steel pipe and fittings? Been used in power plants for years.

Marc

[67drake]

Thanks for the heads up on the PVC guys. I had a mixture of PVC and copper at my last garage some put in by me, some the previous owner, but I didn’t live there long enough to have issues with it. My current house/garage is where I plan to die, so I don’t want it half assed. copper is so pricey these days I already ruled that out. Guess I’ll have to look at the black pipe pricing. That’s what they run the compressed air at work with too.
I know pex is the modern thing, but I absolutely hate the way it looks installed, my OCD bounces off the rev limiter. I learned to plumb from a journeyman plumber years ago and he taught me how to make plumbing runs look like art. All the pex installs I see look untidy, even when done professionally.

[nas t eh]

I can’t imagine using anything but threaded black pipe. When it bursts I would not want to find out how much damage a PVC pipe could do with 125psi compressed air inside of it.

[Sirrotica]

PEX A or B pipe is not recommended for compressed air usage by the manufacturers. If it gets exposed to UV light, the material is weakened substantially. I can attest to that because the previous owner of my home ran PEX to make an outdoor sprinkling system, and where sunlight gets to it, it will fail on a well water system that is regulated to 45 PSI. I would never trust it to a system at 125 PSI. In 2 years I've had to fix 3 sections of tubing that cracked and leaked. The manufactures say that only 30 days of UV light exposure is enough to weaken it to failure point below the rated working pressure.

There are air systems available that use a different type of composite based tubing that is meant to be used for compressed air, but it isn't PEX tubing. The engineered composite tubing is probably 3 times the cost of PEX tubing. Even then, the warranty is only 10 years on the composite systems that are designed for compressed air. Black iron, or even galvanized, would be a much better choice to keep costs at a reasonable level, and make the system safer.

Link to amazon composite compressed air line kits:

https://www.amazon.com/compressed-ai...d+air+line+kit

Since the guy that previously owned my home never saw fit to plumb a real compressed air line system, and ran air hoses up through the rafters, etc. I also am in need of building a real airline system. I'm probably going to go for pipe, as opposed to composite when I get around to building it.

I'm sure there are people that have used PEX for airline that have gotten away with it, but after my experience with multiple failures of PEX water line at much lower pressures, I wouldn't trust it.

[dataway]

Unless the shop is huge ... iron pipe to the side opposite the compressor and then a good hose reel hung from the ceiling in opposite corners of the shop.

[72projectbird]

I run my compressor at 155psi. Ain't no way I'm running PVC pipe. It'll be like working alongside a pipe bomb.

[SRR]

I don't know how much of a run your doing but I would still use copper. Much cleaner air, moisture drops out quicker and easy to make modifications if needed. I have a 30' run with a 50' hose reel on each end.

[67drake]

Originally Posted by SRR

I don't know how much of a run your doing but I would still use copper. Much cleaner air, moisture drops out quicker and easy to make modifications if needed. I have a 30' run with a 50' hose reel on each end.

90-100’, plus fittings

[Stuart]

I would price out the airlines available from Rapidaire, Maxline or equivalent, to see how they compare to copper or black iron pipe. They have both rigid and flexible options available. This is an Amazon link but they're available from many other sources. https://www.amazon.com/compressed-ai...d+air+line+kit

[67drake]

Thanks everyone.
I went back to the hardware store yesterday, and noticed they had a few sticks of 3/4” in the rack where the 1” was supposed to be. So the 3/4” was actually a lot cheaper than what I thought. I talked to the owner and he priced out the black pipe for me, and the cost is in the same ballpark as copper. Copper is a lot more easier for me to work with, so I just went ahead and bought 3/4” and 1/2” copper to do the job.

[mrennie]

Originally Posted by 67drake

Thanks everyone.
I went back to the hardware store yesterday, and noticed they had a few sticks of 3/4” in the rack where the 1” was supposed to be. So the 3/4” was actually a lot cheaper than what I thought. I talked to the owner and he priced out the black pipe for me, and the cost is in the same ballpark as copper. Copper is a lot more easier for me to work with, so I just went ahead and bought 3/4” and 1/2” copper to do the job.

FYI

The limiting factor for pressure in copper pipes is the solder used, not the pipe.

"The Copper Tube Handbook" has lots of great info on this. Coles notes: Use 95/5% tin/antimony solder. It has a ~500-800PSI increase in pressure rating over 50/50% lead/tin solder (depending on temperature). See page 77.

https://www.copper.org/publications/...e_handbook.pdf

Have had copper airlines in my shop for over 10 years at 150PSI and no issues. Copper would always be my first choice due to ease of install and heat dissipation.

[T.Weber]

Just some more thoughts when running a new air line for your garage. If you can run your air line so it has a slight slope back to your air compressor. This will help any water condensation drain back to your compressor. Also if you can - run a 6" nipple up off the main line before making your drop - again, this is to get moisture in the line to drain back to your compressor tank before getting to your air tools etc. I know this will be tough with your OCD but it will sure help in keeping moisture away from your air tools. Ideally if you can also add a water drop to all your air outlets but this involves an addition of 2 ball valves per drop. One before your air outlet and one at the bottom of your air drop. This way any moisture that makes it past the riser will end up in the catch pipe below your air outlet that you can drain off. At the very least do the slight drain back to the compressor and the 6" riser before your drop - you're only adding 2 extra 90's per drop and your air tools will thank you for it.

[nas t eh]

I was just thinking, the last few times I used my compressor was to add air to tires. So many shop tools are now available 18volt that I have been slowly switching over. I might not ever run a tool on air again.