Plumbing a shop for air compressor

[D60]

I did a rapid air kit, pricey but my shop isn’t as big as yours. It’s easy to use thou.

That's the Grey Poupon of approaches But if it works, it works!!

 

[Chris142]

You're screaming into the wind. I've given up, figuring one of two things:
1) natural selection will occur
if not, proceed to
2) God watches over children and fools

It's not my choice for pipe or my doing. Just seems to be the way it's done here

 

[clinebarger]

Worked in many shops that used Schedule 40 PVC, Failures were on older systems & never actually hurt anyone.....What's weird is trying to patch an old system didn't seem to work, It would blow apart where a new coupler was glued onto the old pipe??

Have a mixture of 3/4" Rapid-Air & 3/4" Hydraulic Hose for all main branches & drops.

 

[Hohn]

That is because atmospheric compressed air systems are not typically inspectable by a inspection dept...........trust me I know.

Just because they did not say anything, does not make it ok.

https://www.charlottepipe.com/uploads/documents/technical/ISI.pdf

an excerpt:
Testing with or using compressed air or gas in ABS / CPVC / PVC pipe or fittings can result in explosive failures and cause severe injury or death1. NEVER test with or transport/store compressed air or gas in ABS / CPVC / PVC pipe or fittings1. Similarly, testing with or using compressed air or gas in Cast Iron pipe or fittings can also result in explosive failures and severe injury or death2. NEVER test Cast Iron pipe or fittings with compressed air or gas2.

Above in #4, I advise against CPVC and PVC for this application, but also advised for safety concerns what could be done to help lessen the danger.

It's worth clarifying that "black iron" pipe is actually steel and not cast iron.

Cast iron is discouraged because it is brittle and can fracture explosively similarly to how the plastics do.

But black pipe is steel and much more ductile and is perfectly safe for compressed air. It will rust and spring pinhole leaks eventually, but it won't explode or fracture.

 

[burbguy82]

It's worth clarifying that "black iron" pipe is actually steel and not cast iron.

Cast iron is discouraged because it is brittle and can fracture explosively similarly to how the plastics do.

But black pipe is steel and much more ductile and is perfectly safe for compressed air. It will rust and spring pinhole leaks eventually, but it won't explode or fracture.

Sure. But that is not why it is dangerous. It is the air pressure within the system that creates the danger. Pinholes in systems are very dangerous, espeically in steam systems. Will cut a broom handle right in half.

The link I posted was having to do with pressurizing a system, and its dangers with plastic pipe and cast iron......obviously, cast iron does not apply here.

Edit: it is common for drainage systems to have 30-40psi while being tested.........with water under head pressure......it is not the pressure that is the danger, in this case it is what the system is being pressurized with. 5psi in a 4'' pipe will kill......30 psi with water will be annoying.

 

[walterjay]

Plumber here like Burbguy82. Never never never use Sch 40 plastic pipe for compressed air. Trust us.

 

[Hohn]

Sure. But that is not why it is dangerous. It is the air pressure within the system that creates the danger. Pinholes in systems are very dangerous, espeically in steam systems. Will cut a broom handle right in half.

The link I posted was having to do with pressurizing a system, and its dangers with plastic pipe and cast iron......obviously, cast iron does not apply here.

Edit: it is common for drainage systems to have 30-40psi while being tested.........with water under head pressure......it is not the pressure that is the danger, in this case it is what the system is being pressurized with. 5psi in a 4'' pipe will kill......30 psi with water will be annoying.

A pinhole in a shop air system at <175psi isn't as big a safety issue as the industrial setting you describe with steam, IMO.
Yes the pressurizing media matters, because it determines how much energy is stored by that compression. (Bulk modulus is the term that comes to mind).

IN a home shop, it will take decades to get anywhere near rusting through reg sch40 black pipe. More if it's galvanized.

 

[burbguy82]

A pinhole in a shop air system at <175psi isn't as big a safety issue as the industrial setting you describe with steam, IMO.
Yes the pressurizing media matters, because it determines how much energy is stored by that compression. (Bulk modulus is the term that comes to mind).

IN a home shop, it will take decades to get anywhere near rusting through reg sch40 black pipe. More if it's galvanized.

well it sounds like you know more than me.