Failsafe Manual Valve for Aggregates

Aggregates are a popular media type in the building and construction industry, and consist of different sized, usually hard particles or pieces of material including gravel, sand, recycled concrete, slag, topsoil, ballast, Type 1 MOT, and geosynthetic aggregates.

When travelling through silos, hoppers and pipework, these aggregates often need a valve to stop/start the flow process. Pinch Valves are the ideal valve type for this scenario, with their simple construction and straightforward performance.

Sack Filling with Two Types of Pinch Valves

Here, a company dealing with aggregates are using two different types of Pinch Valves from AKO to aid with a sack filling application.

Both valves are situated on the bottom of the hopper which is holding the aggregates. The orange coloured OV type manual pinch valve with a handwheel is being used as a fail safe valve, with the white coloured VF pinch valve set on a timer. The VF type white pinch valve is the secondary option in case the OV pinch valve sleeve fails.

For this particular system, the white VF valve is held closed at 2.5 BAR, holding the gravity fed aggregate from falling through. Both valves are kept closed until the filling process is started, which is when the manual OV valve is opened up using the handwheel and the VF valve is set on a timer to open up, allowing the aggregate to fill sacks as required for 30 seconds. The timer then closes the VF valve again once the bag/sack is full.

The OV valve is then manually closed using the handwheel to act as the fail safe option.

The OV valve also helps when it comes to maintenance. For example if the rubber sleeve inside the white VF valve needs replacing, then the OV manual valve can keep closed to hold back the aggregate media while the sleeve replacement takes place.

Abrasion Free Pinch Valves

The Natural Rubber Sleeve inside both of the manual and pneumatic pinch valve used within this application are resistant to abrasion. The sleeve material is strong and durable, but still has excellent elasticity to open and close at lightning speeds.

Sleeve replacement for rubber valves is very simple and quick compared to other types of valves on the market, resulting in less downtime. The rubber sleeve is also the only wearable part that needs replacing in AKO Pinch Valves, giving the products an excellent total cost of ownership.