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What you need to know about pneumatic valves: the basics

| written by twg

Pneumatic valves do a lot of things – but they’re mostly known for doing four specific things: controlling pressure, controlling flow rate, and controlling both the direction and the amount of air that moves through a pneumatic system at a given point in time. Applications everywhere depend on pneumatic valves to control their systems.

Today, we’re going to discuss some of the basic forms of pneumatic valves and what role they play in the every day function of the systems that they help support. Let’s jump right in!


Pressure relief valves

Whether it’s radiator’s or frankly – anything that deals with the steam that comes from boiling water – we have needed a safe and efficient way to manage it. Pressure relief valves do exactly what their names says they do. They have spring-loaded valves that are designed to open and relieve pressure once that pressure gets to a certain point. You’ll commonly see these valves used in connection with compressible and incompressible fluids in devices ranging from air storage to large, centralized compressors.

Flow control valves

Most pneumatic systems feature what we call flow control valves. These valves help regulate the speed of whatever fluid so happens to be in the system. They’re designed specifically to respond to signals sent from either a control mechanism or a temperature gage. Think of flow control valves as a traffic cop. They can either control flow through variable restriction – which allows the flow of fluid in multiple directions, sometimes simultaneously or; they can limit flow to one direction only. It all depends on the needs of that particular pneumatic system.

Directional Control Valves

Just like with flow control valves, directional control valves are among the most important components of pneumatic systems. Directional Control Valves are actually an exceedingly large class of valve that’s made up of a lot of sub-‘species’ so to speak. There are an endless number of variants to choose from.

Directional control valves allow fluid to flow in different paths from various sources. They normally feature an operator that shifts a valve between positions, but they can be controlled both electrically or mechanically.


When it comes time for you to choose a pneumatic valve, it’s important to do your homework. While the three main families may seem simple enough to understand at first glance – the truth is that there is a lot of variance from component to component and manufacturer to manufacturer. If you’re unsure of where to start, simply give us a call and we’ll gladly assist you in finding a pneumatic valve that works best for your particular system.