How Do Pressure Control Valves Work?

A Department of Energy survey found that plant operators cite reliability as their top concern for compressed air systems followed by air quality and operating cost. When it comes to a compressed air system, pressure-flow control is of utmost importance for addressing all three of these top concerns. At the heart of any pressure-flow control system is a pressure flow control valve.

Constant Pressure

In a compressed air system, the goal is to maintain constant pressure throughout the system so that air flow is continuous and steady. However, due to things like changes in load demand or compressor cycling, the pressure in the system can fluctuate significantly. Worst case, if load outpaces compressor capability, the system will start lagging and flow will be diminished.

Stored Pressurized Air

Pressure flow control use a carefully metered supply of stored pressurized air to diminish these fluctuations. Pressure-flow control is a broad term for a system that consists of compressed air fed into a large pressurized storage tank. A pressure drop in the system indicates a decrease in flow.  When that drop is detected, a valve connected to the tank opens to increase the pressure in the line and thus supplement the flow.

That valve is a pressure-flow control valve. It is a precision motor driven valve that is electronically controlled by the output from a pressure sensor. The pressure sensor measures the pressure in main line where flow and pressure fluctuations need to be minimized.

The Benefits of a Pressure Flow Control System

A pressure-flow control system improves system reliability by minimizing flow disruptions and maintaining system pressure. Since the valves are motor driven with a pressure sensor, the critical set point can be very precise, down to 1psi. With less pressure fluctuation, compressor cycling can be optimized to run more efficiently. This save operational and maintenance costs for the compressor and other component in the system.  In addition, air quality is improved because less air flows through filters and dryers.

As part of a compressed air system audit, iZ Systems provides recommendations for pressure-flow control systems to improve the performance of a compressed air system. Our experts provide turnkey pressure-flow control systems that fit a plant’s needs. We offer a variety of pressure-flow control valves including single and dual valve systems, high pressure valves, pneumatic valves, back pressure flow control, as well as custom systems.