buried airline

[LutzTD]

I have placed my compressor in an out building and I plan to bring air from there inot my shop and also into the main house. Whats the best line for brying? My first thoughts are 1" copper. I know its expensive but I did pretty good on the compressor cost so I have a little money to play with, and no compressor thump in the shop is worth some expense.

 

[Azmotorhead]

What ever you decide you'll need to run a dryer before the line goes underground.
Otherwise moisture will condense in the line with no way to drain it.

BTW I did that(line underground) in my last house and I used PVC electrical conduit for the underground portion buried 2'

 

[BD1]

I think a little more info would help. Where you located ? climate type ? Frost ? routing, footage length ? tees required underground ? or run individual lines from compressor to each location rather than have joints underground ? Just thinking.

 

[spongerich]

Pex-al-pex might be a good option if it's a long distance. You can get a 320 foot roll for around $200. That's gotta be 1/3 the cost of copper and you can make the run without any joints that might fail underground.

 

[tatra]

just thinking out loud, but could one put in say an oversized pvc conduit and then run a flexible air line [ hose ] that could be seviced / replaced as need be in the future?.......same conduit could also be used for wires / telco and such also?........

 

[ratdoggy]

just thinking out loud, but could one put in say an oversized pvc conduit and then run a flexible air line [ hose ] that could be seviced / replaced as need be in the future?.......same conduit could also be used for wires / telco and such also?........

That's a good idea. Easily access on each end

 

[Zeke]

Whatever you decide, go up on size to account for distance. Otherwise you might see a pressure drop when using an air hungry tool. I like to blow out the shop and blow off parts. That uses a lot of air and I want all of it.

 

[LutzTD]

just thinking out loud, but could one put in say an oversized pvc conduit and then run a flexible air line [ hose ] that could be seviced / replaced as need be in the future?.......same conduit could also be used for wires / telco and such also?........

thats a good idea, whats the biggest rubber line I could use, as the just previous poster said, I want all the air, no pressure drops.

more info.

im in central florida, soil is basically sand, no frost depth at all. distance is about 50ft to the garage and 50 feet to the house. No buried joints

 

[djkeev]

thats a good idea, whats the biggest rubber line I could use, as the just previous poster said, I want all the air, no pressure drops.

more info.

im in central florida, soil is basically sand, no frost depth at all. distance is about 50ft to the garage and 50 feet to the house. No buried joints

It's impossible to "get it all" for any hose, any pipe of any size is going to have friction loss in its run. How far are you piping it (50 feet), at what pressure and at what cfm? As a rule of thumb, a design loss greater than about 3% is unacceptable.

There is a lot more to this than digging a hole and throwing a pipe in it.

Dave

 

[LutzTD]

It's impossible to "get it all" for any hose, any pipe of any size is going to have friction loss in its run. How far are you piping it (50 feet), at what pressure and at what cfm? As a rule of thumb, a design loss greater than about 3% is unacceptable.

There is a lot more to this than digging a hole and throwing a pipe in it.

Dave

I think it depends on the end use. I worked in plants that ran air 300-400 feet with no appreciable pressure drops. I think the biggest user I would have is a pot sand blaster. My building is going to be 60x40 so there would also be the lengths to pipe the building. Im not opposed to 1-1/2 lines if thats waht it takes, just trying to figure out the buried part for now.

 

[casetractorfarmer]

Why not just use black iron should work just fine proubly wont rust out in your life time id go with 1 inch

 

[K'ledgeBldr]

Why not just use black iron should work just fine proubly wont rust out in your life time id go with 1 inch

Though I do like the conduit route- for the ease of adding other "things" if necessary...

I'd go this route.
Eliminate the coupling "joints" by welding them up. Pressure test before you bury.

 

[RVDan]

You could put a small air tank in the shop to buffer any losses.

There is an air plumbing thread somewhere here where someone named Lazerus says copper is illegal for air lines.

 

[SGKent]

I would try to go with something non-metallic designed for air pressure. I've had the experience of seeing both black iron and copper fail in acidic soils. In Ft. Walton Beach FL where my folks used to live we did soil tests to improve the lawn and when we began the ph was close to diluted vinegar. The rain, oak leaves and pine needles etc can make the soil quite acidic.

 

[gorilla]

I ran 50' of air line from my garage to my shop building underground in 3/4" black gas pipe. I chose gas pipe because it's coated for direct burial. It's been in place for about 2 years without any problems

 

[Torque1st]

1/2" Nylon tubing or 1/2-3/4" air hose in buried conduit.

You can construct drip legs for condensation to collect drained by some 1/4" nylon tube at the ends of each run.

Use a receiver tank inside each structure as an accumulator for high demand applications as mentioned by RVDan.

 

[chadman]

CTS water line works great.

 

[LutzTD]

I ran 50' of air line from my garage to my shop building underground in 3/4" black gas pipe. I chose gas pipe because it's coated for direct burial. It's been in place for about 2 years without any problems

Im likeing the black pipe option. The soil here is acidic as mentioned above due to the oak trees. I am not sure about the welding process though, is this just a **** weld? I would be more comfortable using fittings and just wrapping the fitting to protect them. any thoughts on a way to wrap them?

 

[LutzTD]

CTS water line works great.

I have buried water lines here that are shallow buried. As it turns out I have a good data set. They buried PVC and CPVC here. the CPVC being yellowish. Appearenty something in the soil or water here makes these very brittle over time. I have replaced most of those runs with PVC due to constant nuisance leaks.

 

[srmofo]

I plan to run from my shop to my house. 1" pex-al-pex inside of conduit With the cable and ethernet line. Its cheap and I can pull new pex if it ever develops a problem. Moisture is not a concern of mine

 

[Motofixxer]

Another idea is to find a local hose shop and purchase almost any size hose. You could check into some 3/4" hose and just run it through a PVC sleeve. Make sure to dry the air well before the underground line. I believe the air hose is only $1-2/ft + fittings.

 

[BD1]

Im likeing the black pipe option. The soil here is acidic as mentioned above due to the oak trees. I am not sure about the welding process though, is this just a **** weld? I would be more comfortable using fittings and just wrapping the fitting to protect them. any thoughts on a way to wrap them?

Not sure what coated black pipe is called in your area but by me it's tape coat. Pipe is coated with plastic material manufacture applied normally sold in 21' lengths not threaded with about 6" of exposed pipe on each end. The pipe can be threaded or use socket weld fittings. The joints are wrapped with same type of coating in a roll form. If threaded underground you can use extra heavy steel black pipe threaded couplings or a socket weld . In place of a 90 elbow we bent one in a cheap harbor freight pipe hydraulic bender. Worked fine and saved joints.

 

[gorilla]

When I installed the air line to my shop I used threaded fittings and a good teflon pipe dope. I had no leaks that I could find with a bubble test and no pressure drop on a leak down test. I wrapped the fittings with a good quality electrical tape although their is a tape made for this use. I could have welded the pipe but I can see no good reason to do so. It seems to me that if one wished to run an air hose through a PVC pipe that you would need to use electrical conduit with long sweep elbows and SLB's to keep from kinking the hose and to be able to pull it. Has anyone actually done this or is the hose in the pipe speculation?

 

[chadman]

I have buried water lines here that are shallow buried. As it turns out I have a good data set. They buried PVC and CPVC here. the CPVC being yellowish. Appearenty something in the soil or water here makes these very brittle over time. I have replaced most of those runs with PVC due to constant nuisance leaks.

We used the black coiled water line.

 

[LutzTD]

We used the black coiled water line.

can you send link? is this the same stuff they use for geothermal?

 

[Chaz]

I'd run a sleeve of 4"PVC and push the air hose through that. Its a real hassle to dig up **** after slabs and foundations are on top of it. I sleeve under every sidewalk and slab before I pour. Then I mark its location on the slab Its amazing how often those sleeves come in handy

 

[mad57]

If you go with pvc or plastic pex make sure to run a tracer wire closer to the surface that way 10 yrs later you can find it .

 

[chadman]

http://www.wolffbros.com/cgi-bin/la...CATURL)=POLYETHYLENE_CTS_WATER_SERVICE_TUBING

 

[darkk]

just thinking out loud, but could one put in say an oversized pvc conduit and then run a flexible air line [ hose ] that could be seviced / replaced as need be in the future?.......same conduit could also be used for wires / telco and such also?........

Exactly what we are doing. We have a 3" electrical conduit buried from our old garage to our new garage for the electrical between the two. We are also sliding a 1/2" ID rubber air hose into the same piping. We want the compressor, noise and all to be away from us because the new garage is attached to the house. I don't think I'm worried about the air pressure loss over say 50'-75' from the compressor to the farthest outlet. I've worked in body shops with 3/4" black pipe and 150 psi at the compressor with over 150'+ run lengths and no noticeable pressure loss. This is with 5-7 guys working.

 

[LutzTD]

http://www.wolffbros.com/cgi-bin/la...CATURL)=POLYETHYLENE_CTS_WATER_SERVICE_TUBING

wow thats cheap, thanx maybe ill look at this stuff

http://www.homedepot.com/h_d1/N-5yc...Id=-1&keyword=polyethylene+pipe&storeId=10051


home depot has it for $23 1"x100feet but its only 100PSI. how is it terminated?

3/4" x 100 feet is 160PSI rated its $41

http://www.homedepot.com/h_d1/N-5yc...Id=-1&keyword=polyethylene+pipe&storeId=10051


oops two ratings this 1x100 is $46 and 160PSI



http://www.homedepot.com/h_d1/N-5yc...Id=-1&keyword=polyethylene+pipe&storeId=10051

 

[chadman]

They have compression fittings to adapt it to threaded pipe or copper just like you would if used as a water line entering your basement.

 

[68rustang]

From your link:

73-degree Fahrenheit maximum working temperature

 

[LutzTD]

From your link:

73-degree Fahrenheit maximum working temperature

ouch, I see that now. Maybe Im back to the black iron pipe, 160PSI seems too close, I will likely run the compressor to 150PSI. Im thinking 1" to the shop and I only need 1/2 to the house, so in the end its not too much. Ill lay a condiut in the same trench for hard wired cable

 

[chadman]

Buried underground 73 deg. won't be a problem. My neighbor has had his in for 10 yrs. now with no issues.

 

[chadman]

The stuff I linked to is rated at 200psi.

 

[LutzTD]

The stuff I linked to is rated at 200psi.

OH OK, Im just not happy with the 30% safety factor, the black iron has a 300% safety factor and I only need to go 50 feet, it would be more questionable for a longer run. Its only $150 to go 1-1/2. I know, overkill, but that my middle name. then I save the cost and space of a second tank inside as someone suggested.

http://www.homedepot.com/h_d1/N-5yc...53&langId=-1&keyword=black+pipe&storeId=10051

I also like things to be available locally. If I order something then Im at the mercy of the mail later if something breaks.

 

[mad57]

I ran galvinized pipe underground from my shed to shop about 30 ft, when i came up and into the shop i went with copper from there on out. i do get water in lines but nothing the reg dont catch, i have a boiler drain right about 4inchs from the main stalk going up to feed the shop , every once in a while i open it full bore with hose on it to outside clears the under ground pipe fast. I did find that the homedepot pipe was garbage, out of round and didnt cut right even with a new ridgid cutter. There for i went with copper inside.

 

[srmofo]

I'd run a sleeve of 4"PVC and push the air hose through that. Its a real hassle to dig up **** after slabs and foundations are on top of it. I sleeve under every sidewalk and slab before I pour. Then I mark its location on the slab Its amazing how often those sleeves come in handy

beating my head against the wall right now for not doing that when I had 2 different utility walks poured last year.....next time for sure....as big as I can get too....like 12" pipe

 

[Torque1st]

Several people here have used air hose inside PVC conduit. Galvanized pipe will also work well. Wrap the joints with pipe tape after painting them with cold galvanizing paint.

 

[LutzTD]

I ran galvinized pipe underground from my shed to shop about 30 ft, when i came up and into the shop i went with copper from there on out. i do get water in lines but nothing the reg dont catch, i have a boiler drain right about 4inchs from the main stalk going up to feed the shop , every once in a while i open it full bore with hose on it to outside clears the under ground pipe fast. I did find that the homedepot pipe was garbage, out of round and didnt cut right even with a new ridgid cutter. There for i went with copper inside.

is it better to put the dryer right after the compressor, or to let the ground cool the air and then dry it on the shop side? I dont really need dry air at the house as I would mostly be blowing things off, maybe an occasional air tool.