A rack and pinion gate consists of a gate frame, blade, rack(s), pinion gear(s), pinion shaft, shaft bearings and a manual or powered shaft drive. Some larger manual drives may incorporate v-belts and/or gear boxes for mechanical advantage. Most powered rack and pinion gates will incorporate some type of mechanical advantage between the driver and pinion shaft.
Rack and pinion gates are used generally as maintenance gates ahead of feeders and other equipment. Due to their simple construction, rack and pinion gates can be relied on to operate after months of inactivity. This is especially important in= powerhouse and industrial applications.
Due to their limited actuating speed, rack and pinion gates are rarely used to regulate flow into a process or onto a conveyor; however, they are sometimes used to discharge small hoppers that always discharge completely. For example, a rock bin that has a maximum capacity of one truckload may use a rack and pinion gate to shut off flow when a truck is not being loaded.
Rack and pinion gates larger than 1500mm are seldom economical due to high operating forces and the resulting expensive drive hardware.
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