Managing Screen Undersize Chute Buildup

Screen underflow chutes are required in order to capture the fine or undersized material that passes through the screening media of a process screen.

Material received from the apertures of a screen deck is distributed across a large surface area, with kinetic energy being distributed across that large surface area. In comparison, a conveyor transfer chute transfers a concentrated and dense stream of material with high kinetic energy following a common trajectory.

With less kinetic energy present, less force is required to bring material to a complete stop or become becoming static, also known as ‘building up’.

As a result, screen underflow chutes experience frequent build up, blockages and can often result in belt drift.

To prevent chronic blockages from occurring beneath screen decks, modern undersize chutes are often lined with rubber, and plastic anti-stick or flexible liners.

Despite the use of these products that promote flow and mitigate build up, screen undersize chutes still require regular intervention from operations teams. The interventions are often required on a daily basis in order to clean microwave blocked chute sensors, dislodge build up and maintain conveyor belt tracking.

Automated hosing can clean microwave blocked chute sensors at regular intervals eliminating bridged protection devices at site.  Preventative hosing of propagation points can dislodge build up before it has the opportunity to propagate. This hosing prevents blockages, ensuring a consistent flow surface that enables consistent conveyor loading and prevention of belt drift on the receiving conveyor.

Most importantly, autonomous management of screen undersize chutes eliminates the need for operators to attend to underflow chutes, removing personnel from the line of fire.