Every minute of every day, millions of cubic feet of air are distributed throughout the buildings on the School of Medicine campus to provide necessary heating, cooling, and ventilation. All of this air is circulated by large fans. The fans are driven by electric motors via pulleys and belts.
Because of the friction between the pulleys and belts, the belts heat up and stretch. To keep the stretched belts from slipping, which generates even more heat, they need to be periodically tightened. Even with this periodic maintenance, over time, the constant friction, heat, and stretching deteriorates the belts to a point when they need to be replaced, much like the belts under the hood of your car.
Fairly recently, WUSM’s Facilities Management Department embarked on a pilot program whereby conventional pulleys and belts were replaced with specialized pulleys and belts. The specialized belts are manufactured with cogs along their entire length that mesh with matching cogged pulleys. This cogged design significantly reduces belt slippage. Reduced slippage results in less heat, and less heat results in longer belt life. In addition to labor savings, the cogged belts transmit energy more efficiently from the motor to the fan, thereby reducing the consumption of electricity.
A conventional belt will last approximately one year, whereas a cogged belt can last up to three years. The pilot program has already saved WUSM thousands of dollars in operating costs.