Conveyor systems represent a large part of the overall plant cost and as such warrants regular inspections and maintenance to protect this investment. Generally, apart from normal abrasive wear, rubber conveyor belting fails through chemical/thermal attack or mechanical damage in one form or another.
Chemical/Thermal Attack Chemicals such as oil, grease, solvents or animal fats should be removed as soon as detected from belts not purposely designed to handle these materials. Belts that are susceptible to attack should be washed down with detergent immediately.
Thermal attack requires correct belt selection and efficient heat transfer/cooling of the belt and product. Mechanical damage. This is best prevented by correct design and installation. Regular monitoring of the system and prompt correction of any faults found will prolong the life of any belt system. The following items should be regularly inspected:
These items perform a very important role in the performance of the belt. If they are incorrectly adjusted they can cause excessive wear due to friction, allow carry back to build up on idlers or pulleys or in some cases cause mechanical damage to the belt.
Any noisy idlers should be looked at immediately. Any seized or broken idlers should be replaced immediately. A jammed idler causes increased friction resulting in excessive cover wear, higher power consumption and may create sufficient heat to start a fire when the belt stops. Also a worn idler can create a razor sharp edge that can cut a conveyor belt in two and contribute to poor belt tracking.
Material trapped between a pulley and belt may cause belt wander and if hard lumps are present they may rupture the belt. Plough cleaners should be fitted wherever a spill onto the return side can be carried into a pulley. Bearings and lagging should be maintained in good condition to help tracking and maintain good power transmission.
This item can be automatic or manual. The automatic take-up is the most desirable as properly maintained it will ensure correct tension of the belt in all operating conditions including starting, running and braking. If for any reason the automatic travel becomes restricted or jammed, belt slippage at the drive may occur, which may cause extreme damage to the belt. The manual take up has the advantages of compactness and low cost. It is however, unable to maintain optimum tension through normal operating conditions. This includes starting, running stopping and changes in belt length caused by changes in ambient and operating temperature. Manual take-up should therefore only be used on short centre or low-tension conveyors.