A double-thread trapezoidal-metric-thread-form screw, which is driven by a motor, raises a nut and the attached load of 16 KN at a speed rate of 12 m/min. The screw has a pitch of 6mm and a mean diameter of 38 mm. The collar (with worn-out surface) has diameters of D = 70mm and d = 40mm. The coefficients of thread and collar friction are both 0.1. Determine the power in kW required to raise the load. Round your answer to 4 significant figures.

A double-thread trapezoidal-metric-thread-form screw, which is driven by a motor, raises a nut and the attached load of 16 KN at a speed rate of 12 m/min. The screw has a pitch of 6mm and a mean diameter of 38 mm. The collar (with worn-out surface) has diameters of D = 70mm and d = 40mm. The coefficients of thread and collar friction are both 0.1. Determine the power in kW required to raise the load. Round your answer to 4 significant figures.

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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