Hard line air supply for shop

[reckedracing]

A friend I know has a commercial building with a comprerssor in the basement and then black iron lines running to 3 looms. Not really huge air volume demand. The black iron is getting pretty rusted inside and the line at the far end of the building furtherest from the compressor has had a severe drop in pressure. If the machine operates at 100psi, use it once and it will drop to 50psi, the lower end range of the machines demand, and it will take 3-4 seconds to return to 100psi.

We took the line apart at the very end and blew out some liquid and a lot of debris, rusted pipe from the inside out. I've been looking into ways to replace the black iron with something that will not rust. My first question is what size piping do you need for a run of that length. I believe the black iron is inch or inch and a half line reduced to 1/2" at the machine. Does the main runner need to be a specific diameter to feed 3 offshoots?

I was considering using DOT airline, or possibly PEX type line.
Believe it or not we ran a bagged minitruck on 150psi using nothing but pex lines and fittings.

 

[DarkHand]

I loves me some Garage-Pak. I have just a few feet on a small 60 gallon compressor but it was stupidly easy to do almost 10 years ago and is still like new.

 

[BigJ]

A friend I know has a commercial building with a comprerssor in the basement and then black iron lines running to 3 looms. Not really huge air volume demand. The black iron is getting pretty rusted inside and the line at the far end of the building furtherest from the compressor has had a severe drop in pressure. If the machine operates at 100psi, use it once and it will drop to 50psi, the lower end range of the machines demand, and it will take 3-4 seconds to return to 100psi.

We took the line apart at the very end and blew out some liquid and a lot of debris, rusted pipe from the inside out. I've been looking into ways to replace the black iron with something that will not rust. My first question is what size piping do you need for a run of that length. I believe the black iron is inch or inch and a half line reduced to 1/2" at the machine. Does the main runner need to be a specific diameter to feed 3 offshoots?

I was considering using DOT airline, or possibly PEX type line.
Believe it or not we ran a bagged minitruck on 150psi using nothing but pex lines and fittings.

Most houses use pex for water now. That'd be my suggestion. Very servicable if you have a "crimper/expander" tool set for the joints, etc.

 

[Jeef]

With PEX don't get the 25 dollar crimper tool that you need vice grips to use it with.

Can't you use regular pvc pipe?

 

[reckedracing]

regular pvc is just about the worst possible idea ever unless you like shit blowing up in your face
for every person thats had it for 20 years there's also some chump who had it in his shop for 6 months before it shrapnel'ed everywhere

i've already got the legit tools for pex
black iron still seems to be a big winner in the corp/business environment so I might just replace the existing and tell them to keep a better eye on their moisture and dumping the tank water once a day

i'm seeing a diameter requirment of 3/4" over a 75 foot run, so if i do get involved with the pex i might have a hell of a time securing the footage i need of 3/4 without going all in on a full roll

 

[awptickes]

Why not suggest an air dryer and replace the black iron pipe?

You could even just install the dryer now and replace the black pipe when there's a lull in workload.

 

[reckedracing]

thats a good idea but i don't know if they'll go for the additional cost

 

[awptickes]

It will save their tools too, not just the air lines.

 

[EGProject]

Theres a company that gets plugged in all the DIY auto shows on Spike that makes a modular aluminum shop air line that uses aluminum piping coated inside and out with a plastic coating.

My shop uses copper pipe.

 

[DarkHand]

Theres a company that gets plugged in all the DIY auto shows on Spike that makes a modular aluminum shop air line that uses aluminum piping coated inside and out with a plastic coating.

I loves me some Garage-Pak. I have just a few feet on a small 60 gallon compressor but it was stupidly easy to do almost 10 years ago and is still like new.

 

[newb]

Copper pipe. 3/4" will flow more then youll ever need. My shop has a run over 100 yards long that feeds 10 CNC's, a handful of manual machines and a few dozen drops for air guns.