Challenged by a customer who needs to drive a slow moving conveyor beneath a surge hopper handling hot material, Rulmeca alpha and beta tested a Motorized Pulley which uses pressurized air to help dissipate heat. Click here to watch video.
Photo shows hot material moving toward the viewer on a conveyor belt at 2 fpm. That slow conveyor speed, combined with the hot material to be handled, caused Rulmeca engineers to suggest a pneumatic heat dissipation system. It consisted of a series of nozzles which directed “factory air” onto the inner face of the Motorized Pulley. To see video, click here.
The air distribution system was successfully alpha-tested at the Rulmeca facility in June 2018. Click here to see the announcement. Normally, each Rulmeca Motorized Pulley relies on the conveyor belt it is driving to continuously pull heat from the face of the pulley. The increase in belt temperature at steady state, when comparing outbound and incoming belt to the pulley, is 3° F +/- 1° F. Since the belt speed is so slow in this application, as alternative means of pulling heat from the pulley face was required.
Photo shows the surface of the Motorized Pulley as it was being cooled by pressurized air. Infrared thermography of pertinent external surfaces combined with the measurement of the internal stator temperature were essential in verifying the validity of the heat dissipation system. Note that the temperature drop at the pulley surface was approximately 5° F.
Graph shows that internal stator temperature peaked at +112° F and cycled +/- 2° F each hour as material was charged onto and discharged from the conveyor. It also shows that ambient temperature remained between 70 and 80° F. Since maximum internal temperature < +250° F, the test was a success.