Pinch valves are somewhat like diaphragm valves. A pinch valve has an elastomeric liner or sleeve through which media flows. A mechanism, or air or fluid pressure, opens and closes the liner by "pinching" it. Thus, pinch valves work as shut off valves, but they also adjust to a full range of openings, serving as proportional valves. Pinch valves have a wide range of applications, but are most effective for sanitary environments, such as in the medical field, as well as for slurries.

Though the pinch valve does not have a typical shaft actuator, here are three common types of pinch valve actuation:

1. Pneumatic pinch valves open and close via air pressure on the walls of valve sleeve.

2. Hydraulic pinch valves open and close via fluid pressure on the walls of the valve sleeve.

3. Mechanical pinch valves usually close via an electric solenoid that raises and lowers a bar over the valve sleeve.

Action Steps
The best contacts and resources to help you get it done

Search pinch valve suppliers for a flow control pinch valve

Pinch valves control flow well. And, as already mentioned, they work as proportional valves, also known as control valves. These valves control the flow rate or pressure level in industrial systems.

I recommend: ASCO Valve is a good source for solenoid and many other types of pinch valves, including proportional and micro-mini. Elasto Valve Products has several series of high quality pinch valves in a wide range of sizes, including some that are quite large.

Choose a fluid or air pinch valve over more expensive alternatives

The pneumatics and hydraulics of pinch valves are exceedingly simple as compared with other types of power actuated valves. In many cases, hydraulic and pneumatic pressure must turn large shaft actuators, but in the pinch valve, the fluid or air simply enters the valve to apply pressure directly to the valve sleeve. This can save money, as well as installation and maintenance time.

I recommend: Head to Arco Associates for pneumatic pinch valves. They will even custom manufacture valves to fit your specific applications. If you're looking specifically for miniature sizes, also take a look at what's available from Marr Valve.

Use the rubber pinch valve or plastic pinch valves for corrosive media

The main corrosion problem with most valves is contact with metal parts. However, when fluid (or sometimes pellets or powder) pass through a pinch valve, all it touches is a plastic or rubber lining.

I recommend: Thomas Ladisch Associates carries pinch valves with various types of actuation. Many of their valves ensure that the only thing a process fluid touches is the sleeve. Red Valve Company covers the range with hydraulic, air, some mechanical, and even the miniature pinch valve. Many of their products are abrasive and/or acid resistant. As necessary, the company seeks creative solutions for its customers.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  If you're looking for pinch valves independent of electrical, air and fluid systems, you're looking for manual pinch valves. They are readily available. Just make sure to get a quality valve that will turn easily by hand.
• •  Pinch valves often attach to tubing (rather than pipe) in sterile applications. A tubing pinch valve has a number of attachment methods, one of the most sterile being via end flanges.