When should operators use polyurethane screening media?

The material a quarry processes and the procedures it employs to do so largely determine the kind of screens it should install. Polyurethane, wire and rubber each accommodate different operations.
This article specifically focuses on poly screens, weighing the advantages and disadvantages associated with using it.

Operating in wet conditions

To supply manufacturers with clean aggregates to make concrete, bituminous mixes and roadbases, quarries are obliged to wash their materials. It’s a key part of the classification process and removes clay, silt, shale, soft stone, roots, twigs and other debris that tarnish the final product's integrity.

Depending on the type of screens a quarry uses, unwanted material may clog apertures and decrease operational efficiency.

Polyurethane resolves this issue, as it becomes slippery when it comes into contact with water. Sediment is easily separated from the final product, creating a more effective washing process. On a side note, authorities across the globe are developing guidelines to assist quarries in either reducing the amount of water they use or implementing more efficient washing methods. For example, Holcim created a water management plan for its Lynwood Quarry in the Illawarra region of New South Wales to capture run-off and reduce its dependence on external water supplies.

Reduced pegging, blinding

Poly ripple screens also reduce pegging and blinding. While the latter occurs when screening media encounters sticky, fine material, the former transpires when irregular products enter the screen apertures but are unable to pass through.

Quarries are always going to encounter pegging and blinding, although there are ways to reduce the frequency of these issues. The key lies in the nature of the poly material.Due to the substance’s flexibility, the screens bend slightly when exposed to vibrations. This allows any gravel or stone to pass through the apertures. Think of an hourglass shape. When material gets stuck in the centre, vibrations expand it so products are expelled.

Ease on wear, tear

One advantage poly screens have over their wire counterparts is they can sustain operations for a longer period of time. This durability is due, in part, to the nature of the material, as well as its light weight, which decreases the amount of maintenance required of the operators.

Although it’s not the solution for every application, poly screening media has a role to play in certain situations, and to the benefit of quarries.  

Source: Locker Group

Leave a Reply

Send this to a friend