Pinch Valve

 Pinch Valves:

• Pinch valve uses a round elastomeric sleeve connected to the valve body from inlet to outlet that completely isolates the liquid passing through the valve from all internal valve components.
• Closure is made by a movable closure element outside the sleeve that pinches the sleeve between the element and the valve body.
• This type of valve is used for slurry and other liquids with highly corrosive properties.

Working Principle:

Having the simplest valve design, pinch valves comprise of a flexible elastomer body that obstructs the flow of media through the pinching mechanism of the rubber sleeve, which is the main working element. The rubber sleeve is pinched closed either by the application of fluid pressure or mechanically in the body. It is squeezed at the valve’s mid-section, clamping or pinching its walls together to tightly close the flow path.

Pinch valves are controlled through a linear motion method. In its simplest form, the valve may comprise of a length of elastomer tube equipped with a mechanism of pinch bar, providing a closure in order to stop and prevent from over-pinching of the tube. The pinching mechanism is typically carried out by a molded rubber tube that is placed inside a body. This can be done through a simple screw operated working principle, where the pinching action is achieved from only one side of the tube. It may also be possible that a differential screw is used for controlling two pinching mechanisms that are working in vertical opposition to one another.

Advantages:

• In pinch valves fluids are not come in contact with its metal parts.
• Low maintenance
• Low operating cost
• Leakage proof
• Ideally corrosion resistance
• Easily operated, user friendly valve
• Smooth flow
• Perfect throttling
• Seat less and glandless valves
• Preferably handle abrasive and corrosive media
• Easy replacements of the sleeves

Disadvantages:

• It cannot be used in high temperature-pressure applications and gas media.