A vertical power screw with double start square threads of 50 mm mean diameter and 11mm pitch is raised against a load of 10 kN by means of a hand wheel, the boss of which is threaded to act as a nut. A thrust collar, taking up the axial load,supports the wheel boss and has a mean diameter of 60mm. The coefficient of friction is 0.18for the screw and 0.16for the collar. If the tangential force applied by each hand to the wheel is 200 N, find suitable diameter of the hand wheel.

A vertical power screw with double start square threads of 50 mm mean diameter and 11mm pitch is raised against a load of 10 kN by means of a hand wheel, the boss of which is threaded to act as a nut. A thrust collar, taking up the axial load,supports the wheel boss and has a mean diameter of 60mm. The coefficient of friction is 0.18for the screw and 0.16for the collar. If the tangential force applied by each hand to the wheel is 200 N, find suitable diameter of the hand wheel.

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 7.57P: The square-threaded screw with a pitch of 10 mm and a mean radius of 18 mm drives a gear that has a...

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