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.

Pressure Control Valves

Proportion-Air, Inc. is the pneumatic industry leader in manufacturing electronic air pressure control valves. Whether you need a high pressure regulator for bottled gasses, a low pressure regulator for inches of water column, a precision pressure regulator for lab or medical grade applications, or even an oxygen regulator cleaned and compatible for oxygen service. Proportion-Air has a family of air pressure regulators right for you.

Flow Monitors

The Proportion-Air, Inc. F-series is a line of flow transducers designed specially to provide real time flow measurement of compressed gasses for many demanding applications. The Proportion-Air, Inc. F-Series design utilizes differential pressure technology to sense the pressure change across an internal venturi. This differential pressure (DP) measurement is fed into an onboard electronic circuit that converts the DP signal into a linear analog output signal which represents the flow through the F-series. The DP sensor and circuit are completely analog to offer the fastest possible response time and eliminate digital stepping often seen in flow transducers of other technologies.
The Proportion-Air, Inc. F-series product is available in flow ranges from as low as 1 to 20scfh and as high as 25 to 250scfm. Pipe sizes range from 1/4" to 1 1/2". Both NPT and BSP threads are available. The differential pressure technology incorporated in the Proportion-Air, Inc. F-series flow transducer is ideally suited for rugged commercial and industrial applications. This technology allows measurements of flows from 10% to 100% of the maximum calibrated range. The benefits of real time measurement make the F-series a must in many rapid sequence applications.
Proportion-Air's "Real Time" Flow Control
Proportion-Air, Inc. F-series flow monitors are the heart of Proportion-Air's new "Real Time" flow control system Proportion-Air's electro-pneumatic controls, which have been a staple of the industry for over 20 years, can be electronically reconfigured to accept feedback from out F-series flow monitors. This combination of components provides a complete flow control package for flow ranges as low as 2 to 20scfh (0.016 to 0.16 L/Sec) to 250scfm (118 L/Sec). Because the feedback is "Real Time" the results are a series of flow controllers that respond instantly to change in command or system fluctuations. This fast response allows manufacturers and machine builders to use flow control in applications using high cycle rates "Real Time" response can even allow for increased cycle rates thus higher productivity.

Flow Control Valves

The FCV is a proportional flow control valve. The FCV consists of an electronic pneumatic positioner, a pneumatic valve actuator, a LVDT position sensor to continuously monitor the valve position, a robust angle seat valve, and a parabolic shaped linear valve trim all in one complete package

Why choose the FCV proportional control valve?

  • The FCV is electronically closed loop.  The internal LVDT position sensor is used to continuously monitor the valve position.  The FCV electronics drive and hold the desired position regardless of pressures, viscosities, or age and wear.  The LVDT output also provides you an electronic valve position indicator signal
  • The FCV flow control valve is a complete package.  With other technologies, like actuated ball valves, the valve, pneumatic positioner, the electronic control valve, and the electronic valve position indicator has to be purchased from different sources to be assembled and calibrated by the user.
  • The FCV proportional flow control valve is flexible. It can be used as a pneumatic flow control valve in large cylinders for pneumatic cylinder speed control, as a water flow control valve the FCV can control cooling water for temperature control of molds (casting), and as a pneumatic steam valve the FCV can act as a flow rate control valve for mold heating applications.

Special Regulators

An industry leader in the manufacture of air volume boosters, pressure reducing regulators, air relays, vacuum regulators, pneumatic relays, and high pressure regulators. From low to high flow regulators and many body materials such as brass air regulators compatible with oxygen cleaning. Specializing in precision air regulators we can cover all your pressure control valve needs.

Ultra High Resolution Pressure Controls Valves


The QPV is a high resolution proportional pressure regulator or servo valve designed to precisely hold the set pressure under flow or in the presence of leaks. The control circuit affords precision pneumatic control by only opening the proportional solenoid valve the required amount to maintain precise pressure control under flow.