Q1) A start square (normal series) power screw of 40 mm nominal diameter is acted upon by an axial load of 50 kN. The outside and inside diameters of the screw collar are 40 mm and 20 mm respectively. The coefficient of friction for both thread and collar are 0.2. The screw rotates at 20 r.p.m. The allowable thread bearing pressure is 15 N/mm and the shear yield strength is 70 N/mm?. By using the uniform wear theory, determine a) the dimensions of the screw and the height of the nut, b) the number of the threads of the nut which are in engagement with screw, c) the stresses in the screw and the nut, d) the power required to drive the screw and state if the design is safe or not.

Q1) A start square (normal series) power screw of 40 mm nominal diameter is acted upon by an axial load of 50 kN. The outside and inside diameters of the screw collar are 40 mm and 20 mm respectively. The coefficient of friction for both thread and collar are 0.2. The screw rotates at 20 r.p.m. The allowable thread bearing pressure is 15 N/mm and the shear yield strength is 70 N/mm?. By using the uniform wear theory, determine a) the dimensions of the screw and the height of the nut, b) the number of the threads of the nut which are in engagement with screw, c) the stresses in the screw and the nut, d) the power required to drive the screw and state if the design is safe or not.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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