Proportion-Air built our reputation on electronically controlled high flow valves capable of very high flow rates. Whether using one of our compact, single-unit devices with integrated volume boosters or our assemblies with industry-leading downstream pressure transducer technology, Proportion-Air has a solution for your biggest high-flow challenges.

Understanding the flow required for your application is critical to implementing the correct product in your process. If you are unsure of your flow rates, no problem! Our application engineers are great at asking the right questions and gathering the required information to calculate the flow you require and recommend the best high flow valves to meet your needs. Over-sizing flow rates is (generally) not a problem. But under-sizing the flow rates can mean the difference between success and failure. If your high flow valves do not flow enough for your process, speed and pressure is lost downstream. At Proportion-Air, we have a multitude of products and methods for achieving a broad range of flows and pressures – even more than you see on our website. So please give us a call and let us help you with your application.

The QB2, Volume Booster & Transducer

An assembly produces a high flow electronically controlled pressure package. By adding the transducer, the mechanical inaccuracies & hysteresis of the volume booster is compensated for and accuracy of ±0.5% is achieved.


The downstream pressure transducer feeds an electronic control signal back to the electronic high flow valve (pilot) so that the control loop is closed around your actual output pressure. This allows us to overcome any mechanical inaccuracies and hysteresis issues inherit in the mechanical regulator we are piloting.

Three distinct components

1 – QB2X Electronic Pressure Regulator provides an air pilot signal to the dome of the air volume booster. By controlling pressure to the top of the diaphragm, we control pressure out of the volume booster.

2 – An Air Volume Booster, also known as a dome-loaded or pilot-operated pressure regulator. This can be a pressure reducing valve or a back pressure valve. We have many volume boosters available that can handle different pressures, medias and flow rates. Understanding the application is critical to specifying the best fit.

3 – A DSB or DST Pressure Transducer measures output pressure of the volume booster and provides this feedback signal to the QB2. The QB2 adjusts dome pressure (based on this feedback) to achieve the commanded pressure in the process.

QB2 & Volume Air Booster