Pneumatic Pinch Valve (Air-Actuated Sleeve Valve)

The Pneumatic Pinch Valve is an advanced flow control solution developed from the manual pinch valve, designed for automated and reliable operation in challenging media services (slurries, powders, corrosive chemicals). It uses compressed air to squeeze an internal rubber sleeve shut, completely isolating the working medium from the mechanical parts.

⭐ Structure and Operating Principle

This valve is an automated version of the manual pinch valve, with the closing mechanism driven by an external pneumatic device.

1. Components

The valve consists of:

Upper and lower Cast Iron or Cast Steel body halves.
An internal, reinforced Rubber Sleeve (the only part contacting the medium).
Closing mechanisms (valve stem, gate, guide posts).
A Pneumatic Actuator or other optional drive devices.

2. Working Principle

The valve operates using control media (compressed air) acting on the rubber sleeve:

Open State: When no control medium is input, the cavity between the rubber sleeve and the valve body is connected to the atmosphere. The sleeve remains open and tensioned by the internal fluid pressure. The reinforced layers within the sleeve ensure axial and radial pressure balance, keeping the sleeve’s dimensions stable.
Closing Action: When the control medium (compressed air) is introduced into the cavity between the sleeve and the valve body, the compressed air pressure deforms and squeezes the sleeve, completely cutting off the flow.
Isolation: The complete sealing action is achieved entirely by the deformation of the rubber sleeve, ensuring no physical contact between the actuation mechanism and the transported fluid.

📋 Technical Data Summary

Parameter	Details
Valve Type	Pneumatic Pinch Valve (Flow control via rubber sleeve compression)
Body Material Options	Cast Iron, Aluminum Alloy, Carbon Steel
Sleeve Material	Rubber (Enhanced with reinforcing fabric layers)
Actuation	Pneumatic (Air-Actuated) or other customized drives (Electric)
Design/Manufacture Standard	$\text{Q}/\text{JBGN}02$
Flange Standard	$\text{JB}78$ ( $\text{PN}1.0\,\text{MPa}$ )
Maximum Pressure	$\text{0.6}\,\text{MPa}$ (for $\text{DN}25$ – $\text{DN}150$ ) / $\text{0.4}\,\text{MPa}$ (for $\text{DN}200$ – $\text{DN}300$ )

Nominal Size and Pressure Data (Selection)

Nominal Diameter (DN)	Nominal Pressure (MPa)	Working Pressure (MPa)
$\text{25 - 150}\,\text{mm}$ ( $\text{1}''$ to $\text{6}''$ )	$\text{0.6}$	$\text{0.6}$
$\text{200 - 300}\,\text{mm}$ ( $\text{8}''$ to $\text{12}''$ )	$\text{0.4}$	$\text{0.4}$

🚀 Key Advantages

In-Line Flow: The inner diameter of the rubber sleeve matches the pipe diameter when fully open, resulting in minimal local resistance and flow loss.
Zero Leakage: The medium space and the control medium space are completely isolated by the sleeve, preventing both internal and external leakage.
Handles Contaminants: The closing action relies on the sleeve deforming to encompass the media. Even fluids containing solid particles or fibrous impurities will be tightly enclosed and shut off without blockage.
High Efficiency & Long Life: The specially enhanced rubber sleeve can withstand high-frequency opening and closing cycles and resists acids, alkalis, and chemical media, providing a very long service life.
Simple Maintenance: The valve is installed without directionality. If the rubber sleeve is damaged, it can be replaced quickly and simply.
Control Flexibility: Allows for local or remote automated control as required.

🏭 Typical Applications

Pneumatic Pinch Valves are widely used where conventional valves fail due to harsh media:

Chemical and Petroleum Industry (Corrosive chemicals)
Metallurgy and Mining (Slurries and abrasives)
Power Sector (Ash handling, flue gas desulfurization)
Sewage and Water Treatment (Sludge and contaminated water)

⚠️ Important Usage Notes

Air Quality: Impurities and moisture in the compressed air can affect the sleeve’s lifespan. An air filter/dryer must be installed in the air line.
Pipe Cleanliness: Ensure pipes and joints are thoroughly cleaned of impurities and cuttings before assembly.
Maintenance Safety: Always close the air supply valve and vent all compressed air from the actuation circuit before performing any sleeve maintenance.
Low Temperature: To prevent the sleeve from freezing, use dry air (treated with a dryer) when operating the valve below $\text{5}^\circ\text{C}$ .