The corediameter of the double start square threaded screw having a pitch of 12mm is 50 mm. A load of 18kN is lifted through a distance of 180mm. Find the work done(in Joule)in lifting the loadand the efficiency of the screw, when 1. The load rotates with the screw, and 2. The load rests on the loose head which does not rotate with the screw. The external and internal diameter of the bearing surface of the loose head are 60 mm and 10 mmrespectively. The coefficient of friction for the screw is 0.11,whilefor the bearing surface is 0.13.

The corediameter of the double start square threaded screw having a pitch of 12mm is 50 mm. A load of 18kN is lifted through a distance of 180mm. Find the work done(in Joule)in lifting the loadand the efficiency of the screw, when 1. The load rotates with the screw, and 2. The load rests on the loose head which does not rotate with the screw. The external and internal diameter of the bearing surface of the loose head are 60 mm and 10 mmrespectively. The coefficient of friction for the screw is 0.11,whilefor the bearing surface is 0.13.

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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