Vacuum Loader Handling Polymers with Valves

A market leading company working with performance polymers in the UK and beyond, excel at producing bespoke compounds that match their customers specific applications. This company can introduce a variety of additive systems into compounds to refine their performance for different applications.

Specific loading machinery is used to move the polypropylene granules, and an all important valve is required to help with this process. In this case, the company are using AKO pneumatically operated Pinch Valves from the VF range to convey polymers from one point to another in a closed state, and then they are dropping the polymer via another valve in an open state.

Vacuum Loader in detail

The piece of equipment is an air vacuum driven loader, powdered by an integral multi-stage injector vacuum using factory compressed air.

There is a Pinch Valve fitted to the side of the equipment which sucks the polymers into the vessel onto a weighing flap. Once the self-operating counter balance flap measures the correct amount of weight, the flap releases, allowing the polymers to drop down. A normally closed Pinch Valve hovers over a bin, and opens to release the polymers.

Pinch Valve used within this application – VF100.03X.31.30LA

VF model, air operated, aluminium body, aluminium flanges PN10/16 with mild steel bushing contact parts, natural rubber sleeve.

A quick exhaust valve is fitted to the Pinch Valve. A quick exhaust valve allows the compressed air within the valve to escape quickly and the sleeve opens faster as a result.

The polymer passing through the valves on the vacuum loader is ambient in temperature. The valves are normally closed, and operate more than 1000 cycles per day. 3 bar compressed air pressure is used to fully shut off the pinch valves.

The Maintenance & Electrical Engineer on site at this company told us:

Preventative Performance Maintenance with Valves for Polymers

The internal rubber sleeve is replaced annually, but this is done on a scheduled maintenance plan. The sleeves would no doubt last longer if left to carry out further performance. However, some companies like to replace all spare parts at once to try to save unnecessary and unexpected failures, in turn preventing disruptive downtime of the application.

As an additional bonus, the maintenance of re-sleeving a Pinch Valve from AKO UK is extremely simple. The internal rubber sleeve is the only wearable part that needs replacing. In this case, the sleeve could become partially deformed due to the venturi vacuum system being used, which would not give a fully open bore at 100%. A new sleeve is easy to replace and is also low cost, in comparison to other valve types which need multiple spare parts.