A compressor is to run at 250 rpm and requires 75 kW. The driveis provided by V-belts from an electric motor running at 750 rpm.The pitch diameter of the pulley on the compressor is 750 mm andthe centre distance between the motor shaft and compressor shaft is1500 mm. Determine the number of V-belts required to transmit thispower if each belt has a cross-sectional area of 375 mm2, densityof 1000 kg/m3 and an allowable stress of 2.5 MPa. The groove angleof the pulley is 35° and the coefficient of friction between thebelt and pulley is 0.25.
