As energy prices continue to rise, food manufacturers are paying more attention to reducing the power required to transport materials. Within plants, the motors required to transport large volumes of food materials can vary greatly in power consumption. At the high end are pneumatic conveyors that use air to move product at high speed through an enclosed line creating air pressure above or below atmospheric level. High volume pneumatic conveyors typically require larger power hungry motors up to 20-50hp or more that drive fans, blowers and rotary valves.
In the middle range of energy consumption are conveyor belts and bucket elevators. In a typical conveyor belt system, a belt forms a closed loop and runs along two or more pulleys with a drive pulley that allows it to rotate continuously. Bucket elevators move material using buckets attached to a rotating belt or chain. Buckets pick up material, move it to an end point, unload material, and return to the starting point to pick up a new load. To transport a similar amount of high-volume material, belt conveyors and bucket elevators typically use motors of about 25 hp, says Bob Owen (Director of Product Performance at Cablevey).
At the lower end of power consumption are 8-inch tubular drag wire conveyors, which would normally use a 7.5-hp motor to move a comparable bulky amount of material. “The drag cable pulls the solid circular discs (pins) attached to the cable at low speed through a loop, which requires less energy than conventional methods. The large size and number of discs in the 8-inch drives allow a similar amount of material to be transported as traditional belt, bucket or pneumatic drives,” says Owen.