Air lines - Under Ground

Are you honestly going to run your regulator at 175 PSI? That sure makes a compressor work hard.

We ran 2 good Ingersolls at 175psi for about 15 years without issue before I found one big compressor at a sale and moved them down to the farm. The big 4 cylinder unit I replaced them with ran like that for 7 years before it started puking some oil out of it, so it's getting rebuilt now. These are both Commercial/Industrial grade units, not the consumer junk they put the name on. Makes a difference in reliability, LOL

Snap on impacts don't like 175psi, but all of our Ingersoll stuff lasts a LONG time even running that high. There is a definite increase in power running 175psi over 150psi.

Chris
 
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Pressure is pressure as long as nothing is moving. The compressibility and viscosity of the fluid becomes relevant when there is flow within the vessel or if the vessel fails suddenly.

Vessel failures under high water pressure are less catastrophic than failures under high air pressure, which is why they hydrotest vessels above working pressures.

You also have "water hammer" type effects in a working liquid system that won't be nearly as pronounced in an air system. Water hoses will have 600 psi pressure ratings despite the working pressure never exceeding 120 psi, because there are pressure spikes when the hose is full and a tractor drives over it, which aren't as violent in a hose full of air.

This. Hydro tests are at much higher pressures because if the vessel fails, the energy release is less due to the incompressibility of a liquid (mostly). Pressure is pressure though, no mater if it is a solid, liquid, or gas.
 
Faulkner, you ran sch 40 or 80 pvc?

My dad has a Sanborn 2 stage 80gal that runs at 160-170psi. It’s at least 25 years old. One or two head gaskets jobs, few oil changes when I get around to it, and runs everyday. Pressure relief valve is finally giving us some trouble.

Where does everyone buy replacement compressor parts and components?
 
I’m thinking to try the 3/4” pex route. Talked to a buddy in central Texas that is running part of his machine shop on pex for the main runs.
Plus I can bury a a straight run in the ground without connections if I use pex.
 
Not sure how that would work out. 3/4 pex is mighty stiff to be fishing in a sleeve.
Almost stiff as an ol bodark fence post you can hang pipe rail gate from.
 
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