Conveyors are used when material is to be moved frequently between particular points over a fixed path and when there exists a sufficient flow quantity to justify the fixed conveyor expense.[4] Various kinds of conveyors can be planetary gearbox characterized by the type of product being managed: unit load or bulk load; the conveyor’s location: in-floor, on-ground, or overhead, and whether or not loads can accumulate on the conveyor. Accumulation enables intermittent movement of each unit of material transported along the conveyor, while all systems move concurrently on conveyors without accumulation ability.[5] For example, while both roller and flat-belt are unit-load on-floor conveyors, the roller provides accumulation capability as the flat-belt does not; similarly, both power-and-free and trolley are unit-load overhead conveyors, with the power-and-free made to include a supplementary track in order to provide the accumulation capability without the trolley conveyor. Examples of bulk-handling conveyors are the magnetic-belt, troughed-belt, bucket, and screw conveyors. A sortation conveyor system is utilized for merging, identifying, inducting, and separating items to be conveyed to particular destinations, and typically consists of flat-belt, roller, and chute conveyor segments together with various moveable arms and/or pop-up wheels and chains that deflect, push, or pull items to different destinations.[6]