• speeding train banner
  • Untitled-23
  • pro-air-slider-4
  • Pro-air-slider-3
  • pro-air-slider-2
  • pro-air-slider-5
  • pro-air-slider-1

Proportion-Air, Inc. is a manufacturer of electronic air pressure regulators and air flow control valves. Founded in 1985 by corporate President Daniel E. Cook Proportion-Air offers a large family of electronic air pressure regulators and air flow control valves that allow you to select the best product to match your exact application requirements.

Low Flow Control

By matching the correct model and flow rate of air flow transducer to the appropriate size of Proportion-Air control valve, a complete closed loop mass air flow control package is realized. For flow rates below one standard cubic foot per minute (scfm), an F-series flow transducer can be used as electronic feedback to an FQPV control valve. The FQPV has an internal analog proportional/integral/derivative (PID) control circuit which matches the user provided electronic command signal to the electronic flow rate feedback signal from the F-series flow transducer. The circuit achieve this by modulating the drive current to a linearly variable proportional solenoid valve inside the FQPV control valve. Because direct proportional solenoid control is limited to low flow rates, this complete flow control package is limited to 1 scfm. However, direct control with a proportional solenoid does allow for extremely high resolution flow control.



The QB4 closed loop electronic pressure regulator can handle flow rates as high as 200 scfm forward flow and 300 scfm exhaust flow.  It works with pressures from vacuum to 150 psig.  The unit is made up of two solenoid valves, an internal pressure transducer and an electronic control circuit mounted to an integral volume booster. Output pressure is proportional to an electrical input (command signal).  Command signals come in a choice of either a differential 0-10 Vdc or 4-20mA.

QL3 High Resolution Pressure Control Valve


The QL3 allows high volumes of air to move quickly and precisely at pressures up to 150 psig using proportional solenoid valves with a unique analog PID circuit.  Ideal for use with flow meters, it provides high resolution and smooth pressure control at high and low flow rates and avoids the “steps” prevalent in most feed and bleed I/P’s. The output is proportional to the electrical input or command signal.

Proportion Air also has product distributors all over the world.

Here is a complete list of our International Distributors.

Call Us from Indianapolis : 317-335-2602

Let's Talk: 877-331-1738