Black pipe or galvanized for shop air lines?

[boggen]

some prespective of what i have here on the farm....

i generally have projects that there are no way to bring to the shed/shop. were i would like to use air tools. including broken down tractor /truck with flat rear tires, or shingling a cabin roof, or something. because of needing stuff else were on farm. i have a small 3200w generator (barely able to manhandle, on the uglier days), a small air compressor 120psi max 7 gallon tank on it, a portable 5 gallon air tank.

i modified the portable air tank, so i can hook it inline, with air comrpessor.. other words.... generator -> air compressor -> short hose -> portable tank -> hose -> what ever tool i need. the portable tank, allows me to run some impact wrenchs long enough before my PSI goes down. or to run air nozzle to clean out a radiator / oil coolers on tractors.

the small air compressor has been used with chisel hammers on home to deal with knocking a hole in basement concrete block wall. to other...

i do have a second older small air compressor as well. that i sometimes TEE together. (so 2 air compressors and portable tank all connected together) to raise my CFM of air and overall volume of stored air pressure. to help run through some projects that demand the extra air. the 2nd air compressor pretty much stays connected and never moves out of the shop/shed.

with my luck, so happen so today, the second older small air compressor, the belt decided to come apart on me :/ thankfully i was able to complete the task with other air compressor. and there been a couple years back, when another air compressor also went bad, and having the backup kept me going on the given project.

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budget still has not allowed it, to buy up a few hundred feet of air hose and more so fittings. to route air through the shed / shop area. and i dread the long 40 foot hose and the stinking mess it ends up getting into. "half time untangling it, vs using a given air tool" and because of that tend to have 3 to 4 short 5 to 10 feet hoses with swivel ends. half coil/spring type hoses, to half straight hoses. allowing me to mix and match. between dragging stuff to tractor / truck outside shed door "checking air pressure" to working air tools inside. impact wrenchs, air gun, sander, etc...

with above said, for my own shed/shop area. i would most likely be better served. with ceiling spools of air hose, that i can grab a hold of, and pull a few feet of air hose out as needed. so i am not tripping over the stuff constantly between air compressor and work site area. this also goes with electrical extension cords. other words my walls are cluttered with storage and storing of tools and my work space is in the center of it all.

 

[ultrarunner]

Same here... everything is brazed copper K and L pipe... without exception.

Sized from 1/2" to 4" copper... (Very little 4"... mostly 3/4 and 1")

I work in a very strict industry, pharmaceutical manufacturing, everything mechanical in the plant is inspected by outside firms, as well as fda and health Canada, you can get shut down for infractions that cost millions sometimes. Because of this they don't want any water or rust in the air system, behind the scenes there are water traps and filters as well as in the manufacturing rooms. The only thing they install and use is 3/4" copper. Been there for 10 years and never seen one fail. I'm buddies with most of the millright mechanics and asked them one day if there's ever been a problem with the copper, they all said no. One of them did copper in his own little shop and loves it.

 

[TomSeller]

some prespective of what i have here on the farm......i generally have projects that there are no way to bring to the shed/shop.... because of needing stuff else were on farm. i have a small 3200w generator (barely able to manhandle, on the uglier days).... and i dread the long 40 foot hose and the stinking mess it ends up getting into. "half time untangling it, vs using a given air tool" .

Right, I do the same, here is my 6 HP diesel generator I haul from place to place to use power tools where I have no power. I hope this method of hauling is OSHA approved since I tied square knots in the strap. Sometimes I haul an air compressor too if I need air tools and power the compressor from the gen.

 

[dcomp]

I know it's already been said but I highly recommend pex plumbing pipe it's easy to work with and I've used it successfully in several shops now.

 

[dragoneggs]

I know it's already been said but I highly recommend pex plumbing pipe it's easy to work with and I've used it successfully in several shops now.

Even though I am a big fan of plastic, being in the composites industry, I personally would not use or recommend PVC, PEX, etc. for air lines. Water yes... and usually this is at lower pressures than air compressors will generate. The factor of safety is lower than that of metal piping, and if it ruptures, it is more dangerous. Cheaper yes and I know people that do use plastic but it is just not the right material for the application IMHO.

 

[grsthegreat]

I ran my shop in copper 3/4" over 12 years ago. Live in frigid climate in a usually unheated shop. Never had any issues.

I DO have a refrigerated air drier attached so i dont have water in the pipes.

In a COLD or frigid environment i would NEVER use plastic pipe....ive seen the results of exploded pipes.

As far as rigid galv vs black iron, id probably use black iron as its cheaper and being indoors you wont have issues with rust anyways.

 

[like2wheel]

The biggest problem with moisture is the heated air from the compressor. The compressor heats the air when it compresses it, so the air will have the ability to hold more moisture. As the air flows out into the system, the rest of the piping tends to be cooler, and the this makes the moisture "fall out" of the air. It's very hard to avoid this, thus why the piping system is designed to accomodate some moisture in the piping. That is all a air dryer is; A A/C unit that cools the air so the moisture will drop out. But even it can't get it all out, especially during high flow rates.

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This is another big reason not to use plastic for the main line from the compressor. Plastic is a poor conductor of heat, & you need the air to cool as much as possible before any water trap or filter. Copper does this best, but iron does it well too. I would not use black iron though, I have seen some 3/8" black pipe almost swollen shut with rust after long term use for compressed air.

 

[MechE1]

Great topic and a lot of good information. I must confess, I ran my small shop with PVC. I realized the dangers and did an extensive amount of research. It’s a temporary shop (couple years) and I when I move the shop it will be copper or pipe, but most likely copper. From what I remember with my research the two main dangers with PVC are rupturing of the pipe and failure at the glued fittings. The rupturing is pretty self explanatory. Higher pressures and colder temperatures will be more dangerous. With the fittings, if I recall correctly, the problems were cycling and that the glues were not designed to work with a majority of compressor oils, aka, they would/could degrade after some time. I’m not sure how true that is, but it seems to make a bit of sense. The cycling issue makes sense too. The pipe/fittings will expand and contract with temperature and pressure changes in the lines. This will eventually lead to failure most likely at a glued fitting.

 

[BHD]

as all ready stated I ran galvanized for air, part of the reason, was avaibility of the galvanized, but also I have some gas line in the building and it is in black pipe, and it should help avoid any mix up of pipe if future changes are done,

 

[chopped]

I do the same for hauling .I used a pair of vice grips to keep a chain from sliding on the forks. Im surprised there isnt a clamp already thought of that would quick clamp to the forks .Im thinking maybe ill take some chain and wrap it around and then weld up some type of clamp for it. I have seen where some forks have the hole cut in them for a ball hitch..hmmmQUOTE=TomSeller;3854941]Right, I do the same, here is my 6 HP diesel generator I haul from place to place to use power tools where I have no power. I hope this method of hauling is OSHA approved since I tied square knots in the strap. Sometimes I haul an air compressor too if I need air tools and power the compressor from the gen.[/QUOTE]