This page lists compressors rated roughly 168 to 192 CFM, in two groups. Jobsite machines: the Chicago Pneumatic CPS 185 and CPS 175 diesel towables, the Atlas Copco X-Air 185 cold weather towable at 189 CFM, and the Chicago Pneumatic CPS 185 KDU utility mount for a service truck. Plant machines: the Atlas Copco GA30 40 HP at 174 to 186 CFM, the GA26 VSD 35 HP at 183 CFM, the GA22 and GA26 VSD+ at 179 CFM and 175 PSI, the Chicago Pneumatic CPCG 40 HP gear driven screw at 180 CFM, and the CPVSM 40 HP variable speed at 187 CFM.

What 185 CFM supports

185 CFM is the standard rental yard towable because it runs two 90 pound paving breakers at once, or one breaker and a rock drill, or a 3/8 inch sandblast nozzle at 100 PSI. In a plant, 185 CFM covers 50 to 60 air stations, a foundry shakeout line, a large paint and blast facility, or a bottling line with pneumatic fillers and cappers.

Towable or stationary

The diesel towables are built for dust, weather and being dragged between jobs, with their own fuel tank, aftercooler and running gear. The stationary 40 HP screws need 460 volt three phase service and a room, but cost far less per CFM to run. Buy the towable for construction, blasting and utility work; buy the stationary screw for anything with a roof and a power drop.

Fixed speed or variable speed in the plant

The CPCG 40 and GA30 are fixed speed machines for plants that run near full load. The CPVSM 40, GA26 VSD and the VSD+ units slow the airend to match demand and usually save 20 to 30 percent at half load. The VSD+ units also hold 175 PSI for high pressure tooling and long pipe runs.

Power and installation

A 40 HP motor draws about 52 amps at 460 volt or 104 amps at 230 volt. Plan on a dedicated feeder, a compressor room with ducted cooling air, and a receiver of 200 gallons or more.

Dryer sizing

Pair a stationary 185 CFM compressor with a 200 to 250 CFM refrigerated air dryer, or a desiccant dryer for blasting and instrument air. Towables run without a dryer on breaker work; add an aftercooler and filter for blasting or painting.

Related pages

• 150 CFM air compressors
• Towable air compressors
• 20 to 50 HP rotary screw air compressors
• Shop all sizes by CFM