Air Pressure Supply Help - PeachParts Mercedes-Benz Forum

BrierS · #1 07-10-2006, 05:23 AM

In order to run compressed air, with a maximum psi of 120, to three work stations, I need to attach pipe/tube to the ceiling. In all, I will need to use approximately 300'. If I try to use hose, it will sag. What are the most reasonable, light weight pvc pipe schedule(s) to use? I will be using elbows to get it rounted correctly to the three specific locations.

Thanks.
Steve

Breckman99 · #2 07-10-2006, 06:01 AM

Don't know if I would use PVC on that application - Iron would probally be your best bet...

BrierS · #3 07-10-2006, 06:22 AM

I should have added another factor we have to deal with at one workstation. Moisture/rust. We build insulating glass units for historical preservation/replication. With a moisture trap at the source, we are able to keep things under control. My lack of experience with this type of system makes me wonder if there would be a greater chance of moisture and/or rust accumulating in the iron pipe. For years they have just run air hose along the floor to the stations and in the 1.5 years I have been there I have seen that as a safety hazard. The owner is willing to spend (some) money on getting the hoses off from the floor but I don't want to get too expensive. Additionally, the ceiling is about twenty + feet high and I will most likely be doing this project solo on a weekend.

Thank you for the suggestion and I am certainly not ruling it out I just need more assurance on the condensation/rust issue. Handling PVC and attaching it seemed so easy . . . but if it won't work it won't work.
Steve

t walgamuth · #4 07-10-2006, 07:49 AM

how many psi?

i think pvc is rated for at least 100 psi.

if you put a lot of pressure in it you will need to be very careful in prepping the joints. otherwise they will come unglued under pressure. check the rating by the mfgr dont take my word for it.

i think the air compressors have a device that removes moisture from the air so internal rusting shouldnt be a problem. galvanized is usually used, i believe. i have never noted air running through plastic, so there may be a reason you cannot do it. i would check carefully with the pipe mfgr and with the air compressor suppliers. they will know if it will work or not.

tom w

Eskimo · #5 07-10-2006, 08:42 AM

I've seen lots of advice about using PVC for compressed air systems - all of it along the lines of, "DON'T DO IT!".

If I were doing a small installation myself, I'd be doing a little research to make sure that I were using an appropriate grade of copper pipe and fittings. The same research might turn up some suggestions for how best to run the pipe (sloping some runs to help direct the flow of any condensation, installation of low point drains, etc.) and how to appropriately size the pipe.

t walgamuth · #6 07-10-2006, 08:51 AM

i think you will find iron pipe cheaper than copper.

the other points mentioned above sound excellent.

tom w

Eskimo · #7 07-10-2006, 09:09 AM

Quote:

Originally Posted by t walgamuth

i think you will find iron pipe cheaper than copper.

the other points mentioned above sound excellent.

tom w

Please note that I specified, "if I were doing a small installation myself". I find it very convenient to handle copper, and would just as soon not mess about with threading steel pipe for such a job.

BrierS has also expressed some concerns about rust.

He can run the numbers, if he likes, to see how the materials cost would play out against the convenience and desirability of said materials. Horses for courses, and all that.

John Doe · #8 07-10-2006, 10:21 AM

Why not use a $.05 bracket every foot on the tubing or run it through the cheapest sch. pvc conduit you can buy so that it won't sag. I went to a frame shop recently and they had the yellow tubing run through conduit.

OMEGAMAN · #9 07-10-2006, 02:19 PM

according to my pocket ref PVC max usable temp is 140 deg f but pressure is up to 200psi.
I used pvc in a shop once. I had to go to multiple locations and run long distances. I had no trouble at all. Be sure to run large diameter pipe for long distance runs so you dont wind up dropping your volume at the end.

Dee8go · #10 07-10-2006, 02:28 PM

I believe that iron pipe is what I see spec'd most frequently. My company designs and installs photographic facilities which typically include compressed air systems. Unlike those for pneumatic tools, ours are for dust removal and cleaning and have to be free of moisture, oil, and debris.

Iron pipe from the compressor to each work station with quick release fittings at the end seems like the best way to go.

John Doe · #11 07-10-2006, 04:27 PM

Guys--I believe the original poster is installing this in an environment with a high corrosion factor. Iron oxidizes fairly easily, I believe, hence the reason for the original post.

t walgamuth · #12 07-10-2006, 08:34 PM

Quote:

Originally Posted by OMEGAMAN

according to my pocket ref PVC max usable temp is 140 deg f but pressure is up to 200psi.
I used pvc in a shop once. I had to go to multiple locations and run long distances. I had no trouble at all. Be sure to run large diameter pipe for long distance runs so you dont wind up dropping your volume at the end.

this sounds like the way to go. but i would ask around a bit. there could be code issues.

tom w