A major cause of conveyor system irregularities and unnecessary maintenance cost is failure to train employees on the proper use of the conveyor equipment. Improper use of conveyor contributes to poor performance. This can happen when a need arises and the conveyor system is pressed into service without understanding its capabilities.
One of the most common examples is using the conveyor to transport items that are normally regarded as non-conveyable based on size, weight, and configuration, including damaged containers, and containers that have protruding parts or loose flaps/straps. When this happens, there is excessive stress and wear on the entire conveyor system. The result can cause interruption in flow due to jams, and increased risk of injury.
Another common example of improper use occurs in picking operations. When the pick belt stops, often pickers will continue to pick and place cartons/totes onto the dead conveyor belt. There are at least two major problems with this practice that can potentially damage the conveyor equipment, increase operating cost, and lowering system throughput.
First – pick belts are not designed to be started with a fully loaded belt. Even though the static conveyor bed sections, and floor supports are designed for a fully loaded condition; the practice over time will cause permanent damage to critical components of the drive train contributing to premature failure of the conveyor’s power unit and conveying belt. This is true regardless of whether the conveyor is roller bed or slider bed construction.
Second – when the downstream accumulation conveyor receives a large slug of cases from picking, the slug proceeds past a full line sensor, “blocking” the sensor long enough to cause a false signal to be transmitted to the control system. The control system “thinks” the accumulation conveyor is full, and signals the in-feed conveyors (from picking) to prematurely shutdown. This will then setup an intermittent start/stop sequence. Once in this mode, the system is consuming considerably more power (kilowatts of electricity) as a result of the repeated starting and stopping, and at the same time handling fewer cases per minute.