An overhung cast iron pulley transmits 7.5 kW at 400 r.p.m. The belt drive is vertical and the angle of wrap may be taken as 180°. Find: (a) Diameter of the pulley. The density of cast iron is 7200 kg/m3. (b) Width of the belt, if the coefficient of friction between the belt and the pulley is 0.25. (c) Diameter of the shaft, if the distance of the pulley centre line from the nearest bearing is 300 mm (d) Dimensions of the key for securing the pulley on to the shaft. (e) Size of the arms six in number. The section of the ams may be taken as elliptical, the major axis being twice the minor axis. The following stresses may be taken for design purposes: Shaft and key: Tension- 80 MPa Shear – 50 MPa : Tension - 2.5 MPa : Tension - 4.5 MPa : Tension - 15 MPa Belt Pulley rim Pulley arms

An overhung cast iron pulley transmits 7.5 kW at 400 r.p.m. The belt drive is vertical and the angle of wrap may be taken as 180°. Find: (a) Diameter of the pulley. The density of cast iron is 7200 kg/m3. (b) Width of the belt, if the coefficient of friction between the belt and the pulley is 0.25. (c) Diameter of the shaft, if the distance of the pulley centre line from the nearest bearing is 300 mm (d) Dimensions of the key for securing the pulley on to the shaft. (e) Size of the arms six in number. The section of the ams may be taken as elliptical, the major axis being twice the minor axis. The following stresses may be taken for design purposes: Shaft and key: Tension- 80 MPa Shear – 50 MPa : Tension - 2.5 MPa : Tension - 4.5 MPa : Tension - 15 MPa Belt Pulley rim Pulley arms

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.77P: The cone clutch transmits the torque C through a conical friction surface with cone angle . The...

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