Shop airlines

I currently use 1/2" sweat copper for all my airlines in my shop. I am doing an addition to this shop this summer and was wondering if pex tubing would be a good choice for airline @ 125 psi. I havn't checked lately but 6 months agor copper fittings and tube was way way expensive. and nope I won't use PVC.

I have 1/2" copper on about a 50m run from the garage to where i work on my machines. Its at 90psi all the time without a problem. Just ensure the pipe you get is rated for the pressure, i remember on a nother forum this debate came up and there was a pipe that you should never use as it was rated for no pressure, like drainage pipe. It didn't carry mains pressure at all. I got a good deal on my pipe, so i couldn't say no.

Tazza said:

I have 1/2" copper on about a 50m run from the garage to where i work on my machines. Its at 90psi all the time without a problem. Just ensure the pipe you get is rated for the pressure, i remember on a nother forum this debate came up and there was a pipe that you should never use as it was rated for no pressure, like drainage pipe. It didn't carry mains pressure at all. I got a good deal on my pipe, so i couldn't say no.

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I am jealous. I wanted to use copper for sure. Too much cash though. I think that it looks good to run on the surface too. I ended up running actual air hose. Like when you buy a 1/2 inch rubber air hose with the threaded crimps for quick couplers etc....There is a sort of discount store in Canada called Princess auto, i think similar to Harbour freight in the USA, they always have 50 footers on sale so I ended up just running that around my shop. I now have air everywhere in the shop for about 30 bucks. Looks like sh*t though....

coreya3212 said:

I am jealous. I wanted to use copper for sure. Too much cash though. I think that it looks good to run on the surface too. I ended up running actual air hose. Like when you buy a 1/2 inch rubber air hose with the threaded crimps for quick couplers etc....There is a sort of discount store in Canada called Princess auto, i think similar to Harbour freight in the USA, they always have 50 footers on sale so I ended up just running that around my shop. I now have air everywhere in the shop for about 30 bucks. Looks like sh*t though....

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Thats what i was going to do too, not sure how it would have handled being buried. The copper was buried with the power i ran up there too. Its been about 2 years, no problems so far.

Tazza said:

Thats what i was going to do too, not sure how it would have handled being buried. The copper was buried with the power i ran up there too. Its been about 2 years, no problems so far.

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Pex isn't rated for air line use but some other simular products are. I think IPex has a product that is.
There's a reason that black iron pipe has been the traditional material for air lines for years. It allow for good straight runs with no sagging if supported correctly. Anytime there's a low spot in the line water will accumulate there and eventually start coming out at the point of use. When you run a air line all lines should run uphill a little awy from the compressor so that all the water runs back to the compressor. All drops should have a drip leg below the outlet with a drain valve. This allows you drain any water and debris that is there. This sounds like alot of work but if you do it this way you'll always have clean dry air running through your tools.

OldMachinist said:

Pex isn't rated for air line use but some other simular products are. I think IPex has a product that is.
There's a reason that black iron pipe has been the traditional material for air lines for years. It allow for good straight runs with no sagging if supported correctly. Anytime there's a low spot in the line water will accumulate there and eventually start coming out at the point of use. When you run a air line all lines should run uphill a little awy from the compressor so that all the water runs back to the compressor. All drops should have a drip leg below the outlet with a drain valve. This allows you drain any water and debris that is there. This sounds like alot of work but if you do it this way you'll always have clean dry air running through your tools.

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I did a search to find some information to back up what I said about running air lines and this diagram is the best one I found.
http://www.tptools.com/StaticText/airline-piping-diagram.pdf
There's nothing worse than to be using a air tool and have it suddenly start spitting water out the exhaust.

OldMachinist said:

I did a search to find some information to back up what I said about running air lines and this diagram is the best one I found.
http://www.tptools.com/StaticText/airline-piping-diagram.pdf
There's nothing worse than to be using a air tool and have it suddenly start spitting water out the exhaust.

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Had that happen before..... Thats why you are supposed to oil them every time you use them, just a few drops of sewing machine oil in the air inlet, don't give it a massive squirt though.

Tazza said:

Had that happen before..... Thats why you are supposed to oil them every time you use them, just a few drops of sewing machine oil in the air inlet, don't give it a massive squirt though.

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Well actually the oil is just to lubricate the tool. If you have the water coming out of the tool it means somewhere in your system water is acumulating instead of being drained off.
I forgot to mention that you should also have a flexible connector between your compreesor tank and the plumbing to reduce the vibrations transmitted to the plumbing. Here's a picture of mine.
http://i245.photobucket.com/albums/gg49/calfranch/Machine Shop/DSCF0545.jpg

OldMachinist said:

Well actually the oil is just to lubricate the tool. If you have the water coming out of the tool it means somewhere in your system water is acumulating instead of being drained off.
I forgot to mention that you should also have a flexible connector between your compreesor tank and the plumbing to reduce the vibrations transmitted to the plumbing. Here's a picture of mine.
http://i245.photobucket.com/albums/gg49/calfranch/Machine%20Shop/DSCF0545.jpg

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Over here we always have pretty high humidity, you simply can't keep the air all dry. You do the usual things like drain the tank but there is always some. Especially when running air tools that gobble air and the air is hot so the water will not condensate and naturally ends up in the lines. You do what you can, but water is always there unless you buy a proper water separator. I use a water trap for spray painting but the small amount of water i get in other air tools doesn't seem to cause any harm, well not so far.
I agree on the flexible hose to the air line, i simply have plastic/rubber air hose connecting the compressor to the hard air line.

Tazza said:

Over here we always have pretty high humidity, you simply can't keep the air all dry. You do the usual things like drain the tank but there is always some. Especially when running air tools that gobble air and the air is hot so the water will not condensate and naturally ends up in the lines. You do what you can, but water is always there unless you buy a proper water separator. I use a water trap for spray painting but the small amount of water i get in other air tools doesn't seem to cause any harm, well not so far.
I agree on the flexible hose to the air line, i simply have plastic/rubber air hose connecting the compressor to the hard air line.

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What actually is causing the condensate. when the air moves fast through the line it chills the air and then condences? I need to look into some condensate cans for each of my drops. A nice 1.5" sweat copper can would be nice at the bottom of each drop.

Skiddy said:

What actually is causing the condensate. when the air moves fast through the line it chills the air and then condences? I need to look into some condensate cans for each of my drops. A nice 1.5" sweat copper can would be nice at the bottom of each drop.

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Here in the mid USA it gets pretty humid in the summer and I really don't have a problem with moisture in the lines. I get a lot of water out of the tank when I drain it but I've never had problem with it at the point of use. I only use a dryer on the one outlet that I use for painting.

OldMachinist said:

Here in the mid USA it gets pretty humid in the summer and I really don't have a problem with moisture in the lines. I get a lot of water out of the tank when I drain it but I've never had problem with it at the point of use. I only use a dryer on the one outlet that I use for painting.

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Skiddy - from what i have read, the water in the air after its compressed is hot (of course) the water is in vapor form when its like this. The compressed air needs to cool for the water vapor to become water again, if you are using lots of air, it doesn't have time to cool as its being used up as fast as its being generated. This is where you have problems with moisture, if you can allow the water to cool off before use its pretty dry.
From what i was told by a guy that gave me a long length of 1 1/4" bore hose said its shouldn't be used for sand blasting (which i'm using it for....) because this style hose when air is passing through gets hot due to friction, friction generates heat and any moisture in the line us kept in vapor form. For sand blasting you really need dry air or the sand clogs the nozzle, so its a big concern.
For general use, simply draining the reserve tank is enough and installing a drier/water seperator at the end of the line when painting.

OldMachinist said:

Here in the mid USA it gets pretty humid in the summer and I really don't have a problem with moisture in the lines. I get a lot of water out of the tank when I drain it but I've never had problem with it at the point of use. I only use a dryer on the one outlet that I use for painting.

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Sorry... double post

Tazza said:

Sorry... double post

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OK taz so if we made some sort of chiller between the compressor and the tank it should collect a good share of the moisture..... correct? By the way if anyone has been looking for a really good hose reel, I just bought one at lowes for 59.99. It comes with 50' of hose and it works real well. It is the retractable style.

Skiddy said:

OK taz so if we made some sort of chiller between the compressor and the tank it should collect a good share of the moisture..... correct? By the way if anyone has been looking for a really good hose reel, I just bought one at lowes for 59.99. It comes with 50' of hose and it works real well. It is the retractable style.

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Skiddy - thats exactly what the proper units do. They actually chill it to get the water to form, then after it passes through there it uses the heat generated to warm the air back up. You don't want to have cold air passing through your lines, you just want it cool and dry. For general shop use its not needed, they aren't cheap and you need to feed them power to run as well.

Tazza said:

Skiddy - thats exactly what the proper units do. They actually chill it to get the water to form, then after it passes through there it uses the heat generated to warm the air back up. You don't want to have cold air passing through your lines, you just want it cool and dry. For general shop use its not needed, they aren't cheap and you need to feed them power to run as well.

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I think trapping moisture is the best reason to plumb air around the shop, then you build a few traps in and it has plenty of time to cool.
I used all 3/4 plastic, not sure if its pvc, but its been good except buy the stove required more clearance then I thought. I clamped the couplers down to prevent breaking the pastic when coupling hoses though. Fairly cheap and a bit flexible.
Ken

skidsteer.ca said:

I think trapping moisture is the best reason to plumb air around the shop, then you build a few traps in and it has plenty of time to cool.
I used all 3/4 plastic, not sure if its pvc, but its been good except buy the stove required more clearance then I thought. I clamped the couplers down to prevent breaking the pastic when coupling hoses though. Fairly cheap and a bit flexible.
Ken

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I have a 10 hp compressor 3/4 black pipe and use a air chiller to remove the water .When air is compressed it heats up and heated air holds more moisture. with a chiller it removes all the moisture,chillers can be bought at auctions from 100.00 up .I run all kinds of equipment and need dry air Id never go with out one.

renopker said:

I have a 10 hp compressor 3/4 black pipe and use a air chiller to remove the water .When air is compressed it heats up and heated air holds more moisture. with a chiller it removes all the moisture,chillers can be bought at auctions from 100.00 up .I run all kinds of equipment and need dry air Id never go with out one.

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Ok I was just looking at the new Northern tools catalog and they now sell Airline kits that use a push to connect fitting. Very nice looking set up.

Skiddy said:

Ok I was just looking at the new Northern tools catalog and they now sell Airline kits that use a push to connect fitting. Very nice looking set up.

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Ken PVC is very dangerous to use as airline. It explodes like shattering glass and an xray will not show pvc when they are trying to pick all the shards out of you.