When using vacuum on a product passing through a Pinch Valve, the suction from the inside can pull the sleeve partially closed. The way to solve this problem is by piping the same vacuum pressure to the inlet of the Pinch Valve. This will then allow the vacuum to suck from the inside as well as the outside, equalising the pressure.
Sometimes, the Pinch Valve is operated by a solenoid valve. The vacuum can be piped to the exhaust point on the solenoid valve and the method above works in the same way.
We offer an accessory to help further with this problem. Our AKO-VAC System effectively pulls the sleeve open if required, or prevents the sleeve from closing under vacuum.