What Are Pneumatic Pinch Valves?

Functionality Of Pneumatic Pinch Valves

Air operated valves or pneumatic valves are known to use compressed air to generate opening/closing movement. But pinch valves don’t work the same way. When left alone, the pinch valve is open. And under no pressure, the valves allow fluids to pass through. Closing the valve is where valve automation starts.

As mentioned, compressed air systems utilize compressed air to generate motion. The motion then opens the valve. In case of pinch valves, the compressed air is used to generate force on the center of the valve. This pinches the valve from the center, closing it and blocking fluid flow. It’ll help to understand that pinch valves have an internal elastomeric sleeve. So when air is used to generate the force, this sleeve is pushed/pinched to close the valve.

Advantages Of Pneumatic Pinch Valves

Pneumatic pinch valves offer the following benefits:

• Precise flow control
• Suited for corrosive/grainy fluids
• Internal elastomeric sleeve reduces risks of wear and tear
• Replacing the internal sleeve is easy
• Internal sleeve is suited to prevent valve blockages

Pinch Valve Actuation Uses

• Chemical Solution Factory: Pinch valves are suited to handle corrosive chemical fluids.
• Cement Factories: Internal elastomeric sleeve is apt for handling grainy cement fluids.
• Pharmaceutical Industries: Pinch valves prevent contamination and are resistant to medicinal media.

The Fail-Safe Valve Operation

Pneumatic valve automation comes with the risk of system failures. To prevent these system failures from causing large scale operational damage, pneumatic pinch valves come with a protection circuit. If the compressed air, which closes the valve, runs out of power, the circuit continues to keep the valve closed. And once that happens, the valve cannot be reopened automatically. The valve can only be reopened manually. 

This fail safe prevents any large scale damage to industrial pipes. For example, if the valves are closed to prevent the movement of fluids, the pneumatic actuation’s system failure will cause damage or unwanted fluid movement.   

Comparing Types Of Valve Automation

Pneumatic Control Systems	Hydraulic Control Systems	Electric Control Systems	Manual Control Systems
Use compressed air to open/close valves.	Use hydraulic fluid to open/close valves	Use electricity to open/close valves	Use manual labor to open/close valves
Offer precise flow control	Can generate a lot of force	Offer great accuracy and response times	Difficult to achieve precise flow conditions
Generate a lot of force	Much heavier than other actuators	Can be difficult to integrate into working systems	Require no extra installations
Can be noisy	Very noisy	Little to no noise	No Noise
Require frequent Maintenance	Require routine maintenance	Doesn’t require frequent maintenance	Everyday use leads to frequent inspections

FAQs

Where Are Pneumatic Pinch Valves Used?

Pneumatic pinch valves are used in chemical factories, pharmaceutical pipelines, food & beverage factories and the cement industry. This is because they are apt for carrying grainy/corrosive fluids and offering precise flow control.

What Is The Fail Safe Valve Operation In Pneumatic Pinch Valves?

Each actuated valve comes with fail safes to prevent large scale damage. If the external compressed air provider runs out of power, the pinch valves will remain closed with the help of a protection circuit. This circuit takes the place of compressed air and generates a force to close the valve.

Resources:

What is a Pinch Valve? Working, Types, Selection, and Advantages of a Pinch Valve – What Is Piping

Pinch Valve – How They Work | Tameson.com

The Different Types of Actuation – JHFOSTER

Air Operated Pinch Valves: Red Valve |