View Full Version : How do you attach filters/regulators to your plumbed compressed air network?

09-05-2010, 11:04 PM
How do you arrange and connect filters and regulators in your system?

Do you attach them to the wall at each outlet and connect to it with a hose? Any quick disconnects? Do make the short hoses yourself?

Or do you tend to locate them at the devices that use air? Hard connection, hose or quick disconnects?

Do you use splitters on the outlets to feed multiple devices? What kind do you prefer? How do you manage filters/ regulators in this case (install them before the splitter and feed all devices by the same pressure or assign a different regulator per device)?

I have a few devices that require different pressure: tools are at about 90psi, engine hoist- 110-120 psi, sandblaster will, probably, need from 60 to 100 psi, blow guns- 40 psi., etc. Since I have a 2-stage compressor, I may keep up to 175 psi in the tank and pipes. Initially, I thought about keeping full pressure in the tank and aftercooler, and then install a central 3/4" filter regulator to drop the pressure to, let's say 120-125 psi in the central line, but now I don't see how it'll help me avoid multiple regulators at the point of use.

Anyway, could you please share with us your approach? If your have photos, please post them.

09-05-2010, 11:11 PM
I use one main filter/regulator at the source to my distribution line. It is a MotorGuard brand and works really well. It stays at 80-85psi unless I need higher for impact tools, and then I simply turn it up. That unit feeds the dehydrator which then goes to the shop lines. When I paint, I drop the pressure at the gun. I don't use splitters but I do have 9 outlets in a small 24' X 36' shop so there's always one handy. I don't auto-oil any of my lines as my use of air tools is minimal. I oil the tools directly.

09-06-2010, 11:42 AM
I did what chipmaker said, but added extra at points where I need them. A low pressure regulator for the plasma cutter and another for a dedicated spray gun.
it just all depends on what applications you have and if it's worth the extra money for extra filters and regulators. The plasma cutter and spray gun have their own dessicant air dryers as well.

Paul Alciatore
09-06-2010, 01:45 PM
I have designed and installed air systems for operations that had to operate 24/7/365.25. Any down time would cost $s, almost immediately. One of the first things I learned was that EVERY item installed in an air system WILL require maintenance sooner or later so my installations were focused on this fact.

A shop installation is not this critical. It is used on a more intermittent basis and there is usually time for maintenance without incurring great costs due to down time. But some of the principles are the same.

If you need different pressures for different uses, I do not see any way around having regulators. If several of the devices use the same pressure, it becomes a question of the cost for separate regulators vs. the cost of plumbing to the different devices from a single regulator. Only you can answer this using the specifics of your shop.

One of my major concerns was vibration. Vibration can cause failures in things like copper pipe. Or brass fittings! I like galvanized, steel pipe for connections to the compressor. I say galvanized to prevent rust from the ever-present moisture. At the user end, vibration may or may not be a concern. A flexible hose is probably the best solution here. You talk about attachment to a wall or other hard point. Here, vibration as well as the need for connection and disconnection (quick disconnects) is a consideration. A hard line should be firmly anchored at the point of use. An exception to this may be a line hanging from the ceiling, perhaps 10 or 15 feet above. But some kind of restraint should still be employed or you may develop leaks.

Quick disconnects are more complex than simple threaded connections so they will fail more often. I would only use them in places where they are clearly needed. If a filter or regulator needs to be installed for servicing, I would use unions or flare fittings or some other means of disconnecting without completely disassembling the entire line. If there is no vibration at this point, soft copper line could be used to make disassembly easier. But hard fittings (with angles) would be better.

I liked to use a lot of valves to allow servicing of the various components while the system was still in service. A typical configuration for a component (filter, regulator, etc.) would have a valve on each side of the component and a bypass valve to allow continued operation while the component was being serviced. This allowed continuous operation at all times. In a shop it would allow you to operate while waiting for a replacement to arrive. It may or may not be a requirement and the cost of the valves may exceed the cost of the device they surround.

In making your runs, do consider moisture. Unless you go to extreme measures, like refrigeration type dryers, you will have moisture accumulate in the lines over time. You will need a means of bleeding it out. Do put bleed valves at all low points. Do design the horizontal runs with a bit of a slope to allow drainage at one point for that run. If you are interested, I have posted a description of a completely condensation free system I have installed. And I mean not one single drop of water over years of use in the deep, humid South. It also had zero down time over years of use. But it wasn't cheap. Do a search on this board if you are interested.

09-06-2010, 03:37 PM
Thank you guys. Please keep the suggestions coming.

P.S. Paul, I installed a 3/4" copper network with a 40" zigzagged cooling run, inclined main lines, drained (drip leg with valve) dropdowns fed from the top of the mains, terminal drip leg, etc. So I gave a lot of thought to the moisture management aspect of the network. Naturally, some of the outlets will have additional moisture control as needed (plasma, sandblasting, painting...). Now I'm trying to find a better way to manage pressure and attach regulators.