Shop Air Lines

[JB4310]

What pressure are these blowing at? I've seen PVC get brittle not sure what causes it, age, UV but can't be good for it's intended use of Plumbing either. PVC pipe has a pretty high pressure rating but you have to use the schd 40 fittings to keep the rating throughout the project, as opposed to the DWV fittings which have shorter glue hubs.

 

[ray66v]

130-175 psi, all sch. 40, sometimes even sch. 80 fittings.

With the exception of the attachment to compressor, and the pipe to NPT adapters for hoses, in my experiences, fittings were not usually failure points. Solvent welds were never failure points.

We have a retired Master Plumber, who was a Mechanical Contractor, and another guy, who is a plastics Engineer, in an origination I belong to, and they both will agree: PVC is good drain pipe, (although a little noisy), not good for pressure pipe.

 

[eddy622611]

I've never seen copper air lines. It would have to be cheaper than black iron if you consider labor. Is this the same copper tubing with sweat fittings that you would run for water lines? Thanks eddy622611

 

[Scooby074]

I would avoid Pex and PVC. There are nylon type lines as mentioned already that are designed to handle the pressure and oils etc for pneumatic service. Aluminum is also available. It is REALLY nice, but kinda spendy in the larger sizes. Check with a local air compressor (ie:speciality) store. You'd be safer just slinging an old rubber air line than using pex in my opinion.

I have 3/4 black iron. Running it isnt that bad. Just keep it sloped so condensation will drain and try to come out the top of your T for any drops. Also extend the drop past your T where your taking off the air to give the condensation a place to run into so it dont go into your hose. A inexpensive threader can be had at your local chinese importer for well under 100.

Only other thing id recommend is to oversize your line. I did the calculations and speced mine out to be 3/4, but i really should have ran 1" to get the best flow.

 

[kennyd]

I've never seen copper air lines. It would have to be cheaper than black iron if you consider labor. Is this the same copper tubing with sweat fittings that you would run for water lines? Thanks eddy622611

Yes, same stuff, but the "L" copper, not the very thin walled stuff (M).

 

[MrWoodChips]

I've never seen copper air lines. It would have to be cheaper than black iron if you consider labor. Is this the same copper tubing with sweat fittings that you would run for water lines? Thanks eddy622611

I did my shop in type L copper. Not that hard to do, just standard sweat fittings. Some of my quick connect couplers leak a little air, so I've got ball valves inline to leave only the line that I'm currently using charged with pressure. I've got a piece of flex hose from the compressor to a connection on the wall.

One thing I find incredibly useful is a portable air tank, hooked to a quick connect. I normally keep it shut off, but frequently enough I find myself in the need for air, farther away than the 150 feet of air hose that I have will afford. 10 gallons of air under pressure is enough to do a lot of things, like pump up a few tires, blow out a water line to prepare it for winter, etc.

John

 

[IXLR8]

I spoke with an engineer at a PEX heating tube manufacturer and he was surprised/horrified that folks would use PEX for high pressure air. At least their's was only rated for 100psi, to be used in a 30psi max heating system. PEX has a 30day exposure limit to UV, after that it breaks down to the point that the pressure limits are no longer valid. Having seen what PVC can do when it breaks... my shops air lines will either be 'L' type copper or iron pipe. Standard iron pipe lengths will work for me for the most part.. if not, Lowes/Home Cheapo will cut and thread it to the length I need.

 

[JB4310]

I've got a mix of copper, rubber and the new flex plastic,
never done any with iron pipe but if it's a straight simple run then I guess it would be fairly easy and surely durable.
The next one I want to do is a wild run up and over walls and through crawl spaces etc. any kind of pipe would be very difficult, I'm gonna use that flex stuff that was linked to here, I've used a little before, the stuff is great, the fittings are reusable and go together without tools. Not sure if it comes in the larger sizes though, the one I have is only 1/2" outside dia.

I also use valves to isolate the different runs and have a portable tank that I use all the time, seems I always have a low tire on something out of reach of the compressor.

Word of caution which I'm sure most already know, remember to shut off compressor when closing shop for any extended period of time, if a failure did occur causing a total loss of pressure and the machine kept running it wouldn't take long to overheat and cause damage or maybe a fire, I have a light that goes on with the compressor circuit that can't be missed when walking out the door.

 

[ray66v]

Cutting and threading smaller sized iron pipe is not that bad a job. If you plan the job out properly, you will only need to cut and thread a few pieces.

Then, either take them to the hardware store to get them threaded, or buy a hand threader from Harbor Freight for $30, it is not great, but, it will get you by.

There are some tricks you can use, and some really nice hangers, if you can find someone who has experience to help you plan it out.

 

[Flatheadyoungin]

kind of expensive but the garage pak stuff is quality.......quick too

 

[ray66v]

kind of expensive but the garage pak stuff is quality.......quick too

It's really nice, looks cool too.

Some friends of mine used it in their new factory about 10-15 years ago, even though it as expensive, they saved enough in labor costs to make it palatable. When the "old school" Building Inspector showed up to do the final inspection, he had not seen it before, and promptly red tagged it. It got a little heated, because they had tens of thousands of dollars worth of this stuff. They did get it approved later.

I can do steel fast enough, I can't justify the cost. Same problem with the flexible stainless gas lines, (TracPipe), the material cost is murder.

 

[JB4310]

If your looking to use a flexible air tubing to plumb your shop why not use air brake hose. Get a spool of Synflex DOT rated truck air brake hose and plumb away. It is rated for air, is UV resistant and safe in cold temps. It's what I plumbed the air system on my mobile service truck with.

When I first read this I didn't think it was a good idea for a shop application, but when I looked closely at mine that's what it is.
I have 2 types of flex line one is black and one is white/clear, this is what it says on the black line; "Parker Hannifin corp. Air Brake PFT-8B SAE J844 type 3B 1/2OD A DOT" it has those fittings that are reusable and just slip on with a locking collar, do they use those type of fittings on trucks?

The white one has no writing on it, I guess there are many manufacturers making a similar product.

 

[ctpres]

I just ran PVC and pushed reg air thru it. Did this underground, crawl space and over rafters. Lots cheaper than copper or steel pipe and much easier to install.

Sorry guys,left out one word "hose." Ran air HOSE inside PVC, PVC has no pressure and is only to protect hose from rodents, abuse, dirt, roots etc. Sorry again, I need to read my posts before submitting

 

[Pilot]

Copper was easy to run and didn't cost a lot. I run a hose from my compressor to the wall where it connects to a vertical copper pipe, about 6" from the bottom of the vertical. The line continues up the wall, then across for about 20 feet with a slight upgrade so it drains back to the vertical, then down 2', then back across about 10 feet, then down another 3 feet to a water separator and a pressure regulator. I have a ball valve at the bottom of each vertical run.

The reason for the long runs is to allow the air to cool and any water to condense so my tools will get dry air. Western Oregon is not as humid as eastern areas, even though we get a lot of rain, but that's mostly in the winter when the air doesn't really have that much water in it. So after hours of use, I get a little water out of that first valve, a little fog out of the second valve and hardly anything out of my water separator. A similar setup in the south and east would give you a lot more water, I suspect.

I used 3/4" pipe and when running a tool that uses a lot of air such as a die grinder it doesn't seem to keep up with the air flow need, which I don't understand because it goes into the die grinder thru a 1/4" fitting. At least that's my interpretation of what is happening--I hear air continuing to flow thru the pipes for a second after I stop the tool.

Otherwise I am very happy with my air line setup.

 

[EddieWalker]

When I did my shop, I was originally planning on running PVC lines for air. Then I read up on it and saw some of the pictures from people getting hurt when Schedule 40 PVC explodes. You never know when it will happen, or even if it will happen. What really scared me besides the possibility of loosing an eye is how common these things actually happen. It's not rare for them to explode, but fortunately most of the time, nobody is injured to the point that it gets reported. I just don't want to take that chance.

I was debating on whether to go with copper of steel pipe while building the shop, and in the end, found that having two hoses on the air compressor works perfectly. One line is 100 feet and goes through my wall to a garden hose hanger. It's rolled up outside and easy to use on anything out there. The other line is 50 feet and also on a garden hose hanger. Since my shop is only 24 x30, I can reach anything in there real easy with the hose that's just sitting there.

In the shops that I saw pipe used and wanted to copy, there were multiple connections all over the place for all the employees to use. That wasn't something that I had thought of. With just me working in the shop, one hose is never going to be in the way of others. In a commercial shop, you need those multiple connections because of everyone doing something different.

I realized that putting pipe in for air hoses wasn't something that I needed, and in three years of working in my shop, have found that I rarely use my indoor hose more then ten feet from where it's stored anyway.

Eddie

 

[ray66v]

I used 3/4" pipe and when running a tool that uses a lot of air such as a die grinder it doesn't seem to keep up with the air flow need, which I don't understand because it goes into the die grinder thru a 1/4" fitting. At least that's my interpretation of what is happening--I hear air continuing to flow thru the pipes for a second after I stop the tool.

Otherwise I am very happy with my air line setup.

The larger, higher volume couplers are more common now. HVLP spray guns work better with a high volume coupler also. This one, is a nice light weight durable coupler, and the matching plug is considerably larger than a conventional "M" style plug, adds much more volume. http://www.thetoolwarehouse.net/shop/RBL-612.html. The best part is, this coupler will still work with your old 'M" style plugs too. No need to change everything.

 

[JB4310]

I suspect I'm not getting the volume I need to run a Snap-On Impact wrench I have, have enough pressure but the gun doesn't perform as well as it should, I couldn't understand how since the lines are twice the size of the tool adaptors, looks like those unrestricted couplers might do the trick.
Thanks, JB.

 

[ray66v]

I suspect I'm not getting the volume I need to run a Snap-On Impact wrench I have, have enough pressure but the gun doesn't perform as well as it should, I couldn't understand how since the lines are twice the size of the tool adaptors, looks like those unrestricted couplers might do the trick.
Thanks, JB.

Couplers and some types of valves, do slow flow down. But, their short length, usually allows their restriction to be tolerated. However, when your starting to lose volume, usually due to a high draw of air like a grinder, any restriction removed, will help increase it.

If you try to blow through a 3' piece of garden hose, you will find it very easy. Try to blow through 50' or 100' of the same hose, then you feel the resistance.

Keep in mind that at some length, a pipe, just like wire, becomes too small to supply any volume. Then, you have to go up to the next size.

 

[scgargoyle]

When I had my own business, the only type of air line I could legally run was steel pipe. PVC and copper were both forbidden. I ran a main line with a slight angle across the top, then a number of drops, which ended below the air fitting, and had valves so I could let the water out. In FL, we get a LOT of water in the air. That's one good thing about metal pipe- it helps condense the water out faster than plastic or rubber hose.