1. A D-section V-belt is to be used to drive the main power shaft of an agricultural combine (an agricultural combine may be regarded as a combination of conveyors, elevators, beaters, and blowers). The power source is a 6-cylinder, 30-hp internal combustion engine which delivers full-rated power to a 12-inch-diameter drive sheave at 1800 rpm. The driven sheave is 26 inches in diameter, and the center distance between sheaves is 33.0 inches. During the harvest season, combines typically operate continuously 24 hours per day.

a. If a D-section V-belt were specified for use in this application, how often would you predict that the belt would require replacement?

b. Based on the knowledge that it takes about five hours to change out the main drive belt, would you consider the replacement interval estimate in (a) to be acceptable?