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Selection of a Directional Control Valve

Directional Control Valve

In any heavy industrial application, the reliability of a directional control valve is of utmost importance. Choosing the right valve could be the most crucial decision you make regarding failure, downtime, or breakdowns. It is possible to avoid business interruptions, environmental catastrophes, or even loss of life by selecting the right valve.

It is impossible to generalize about heavy industry applications and operating environments. With more than 30 years of creating the most reliable valves in the industry, our engineers at Airmax Valves have compiled the following considerations as part of our recommended valve selection process:

Application Environment for Directional Control Valve

In addition, take into account all applicable environmental considerations. Including the presence of dust, dirt, and insects. The weather and temperature, and the mobility and accessibility of the location. Where the valve will be installed.


It is important to determine what media the valve will control. Which could be compressed air, hydraulic oil, water, natural gas, or inert gases.

Operating and Available Pressure

How much pressure is necessary at the minimum and maximum? Can the valve be pilot-operated, manually operated, or solenoid-operated? If so, will it be internally piloted (InPilot) or externally piloted (ExPilot)?

Flow/Port Size of Directional Control Valve and Location

Valve size should be based on the flow factor (Cv) rather than the application. Different types of valves can have vastly different flow factors for the same port size. The port size method of sizing valves is not the most accurate, as it leads to oversized valves, additional material, unnecessary expense, and higher installation costs. With fully ported internal flow areas, the corresponding port (pipe) connection will have maximum flow.


Are you looking for a 2- or 3-position valve? A 2-position valve, for example, commonly uses to pressurize or depressurize a fluid power circuit. The 3-position valve performs the same function as a 2-position valve but adds a third function to an un-actuated valve. When the directional control valve is in the center position, it performs the third function. For fail-last applications, the most common center positions are all ports barred(APB). The cylinder ports open to exhaust, inlet open to both cylinder ports, and all ports open (APO).

Type of Operators

Understand the required voltage, current, area classification, and ingress protection. Identify the type of electrical connection required. The most common connectors are flying leads, DIN connectors (Hirschman style), and junction boxes. Coil insulation Class F is standard, while Class H is available for high-temperature applications. Power consumption is also considerable. 1.8W, 0.85W, and 0.5W low-power solenoid coils are available.

Regulation or Speed Control of Directional Control Valve

Depending on the application, you may need pressure regulators, speed controls, flow control valves, and/or check valves.

Also read: Water Pressure Reducing Valve for your Apartments

Enhanced Functionality for Safety and Redundancy

There are many ways to enhance reliability and safety with Airmax. Add the Latching/Manual reset and the Shut Off Valve (SOV) for extra safety. Typically, latching manual reset valves use in applications where it is necessary or desirable to manually reset a system. Shut-off Valves provide a pilot control circuit for processes with a variety of control signals in one valve. The valve will shift to the idle position if either signal fails. You can add redundancy by using a Redundant Valve (RS).  By providing parallel control circuits in a single valve, redundant valves prevent process interruptions caused by a single control circuit failure or maintenance. In order to shift to the idle position, both coils must be de-active.

All of these considerations may not be applicable to your particular application. But going through the entire process ensures that none skip. Furthermore, by following this process. You can ensure that you are considering all relevant environmental factors to select a durable, proven, and reliable valve for your specific application.

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