Shop air system...

Thanks,

scott

http://www.oldsmobility.com/air-compressor-piping.htm

I have been planning for an air system for quite some time, I do have a Wilkerson regulator to control the entire system with, it has one inch pipe threads, and as I will be probably be using 3/4 I'll just have to bush it down. It was new, and cheap, so I bought it.

I considered PVC until I read the thousands of items on the internet that tell of horror stories and the state and US OSHAs that have banned it, so plan B is probably copper, doesn't matter if its type L or type M, either one is rated at way more than it needs to be. Nibco also makes Chem-Aire, an ABS type plastic pipe certified for air systems, its glue together and real slick, but actually costs as much or more than copper, just less work to install.

As far as system planning, even for a single user shop, I'd use a loop system, might eliminate unforseen problems down the road. Personally, a single system regulator seems to me better than a system with no regulator and requiring several small ones at each drop.

Charles

--->Paul

That link you provided is one of the better ones that I have seen on the net regarding this subject - at least IMO. A lot depends on your peak air consumption (not necessarily your peak compressor capacity). For instance, are you talking about a typical home shop that only has a single user and that mulitple drops and stations are located for convenience only and not to serve other, simultaneous users? If so, it is hard for me to see where you would need any lines greater than a nominal 3/4", unless you are talking about unusually large air flows. It is not uncommon - in fact it is quite common - for regulating valves to be at least one nominal size, and sometimes more, smaller than the main piping. A 1/2" regulating valve seems large to me for a home shop. You should be able to find out the flow capacity of the regulator. My 3/8" regulator by Watts is rated at up to 90 cfm - a rate way in excess of what I ever use, even for sandblasting from my 17cfm compressor. A similar regulator from the same company that has 1/2" ports carries a rating of up to 200 cfm. It's hard to go just by port size though - regulating valves should be selected on maximum required flow, not port size. The larger regulator will work, but it may not have as good regulation at the low end as one that is better sized for the anticipated load. BTW, each station, if you are planning on having mulitple stations, should have it's own regulator. Best practice is to place regulators as close to the end use as is practical. Your largest pressure-drop issues generally occur downstream of the wall stations where hoses and quick couplers are used. If it were me, I'd run a 3/4" header with 1/2" drops and 3/8" regulators, nothing smaller than 3/8" ID hose (except for a short leader) and a minimum of quick couplers of 3/8" body size. Any filters you add to the system should be sized for pressure drop at maximum cfm (no more than 3-5 psig) and installed upstream of the regulator(s). This is applicable for my use with a 17 cfm, 175 psig, 80 gallon compressor arrangement but it should also be satisfactory for most DIY home-shop use.

Rod

If your threads are good, try Megalok or Gasoila, both available at plumber's or pipe supply houses.

Regards,

Phil Crome