A machine vice as shown in figure below ,has a single start square thread with 28 mm nominal diameter and 3 mm pitch. The outer and inner diameters of the friction collar are 62 and 50mm, respectively. The coefficients of friction for thread and collar are 0.3 and 0.3, respectively. The machinist can comfortably exert a force of 240 N on the handle at a mean radius of L= 217 mm. Assuming uniform wear for the collar, Calculate: a-Mean diameter of the screw d. b-Helix angle a. C- Friction angle o. d-Tightening Torque T in terms of W. e- Friction Torque Tc in terms of W. f-Clamping force developed between the jaws W. g- Overall efficiency of the clamp n. Fixed Moving jaw jaw Screw --- Frame Handle

A machine vice as shown in figure below ,has a single start square thread with 28 mm nominal diameter and 3 mm pitch. The outer and inner diameters of the friction collar are 62 and 50mm, respectively. The coefficients of friction for thread and collar are 0.3 and 0.3, respectively. The machinist can comfortably exert a force of 240 N on the handle at a mean radius of L= 217 mm. Assuming uniform wear for the collar, Calculate: a-Mean diameter of the screw d. b-Helix angle a. C- Friction angle o. d-Tightening Torque T in terms of W. e- Friction Torque Tc in terms of W. f-Clamping force developed between the jaws W. g- Overall efficiency of the clamp n. Fixed Moving jaw jaw Screw --- Frame Handle

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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A single trapezoidal metric thread power screw is to raise a load of 60 kN. The screw has a mean diameter of 34 mm and a pitch of 5 mm. The coefficient of thread friction and collar friction are 0.15 and 0.11, respectively. The collar mean diameter is 90 mm and the screw turns at 150 rpm. Determine the total torque required to raise the load in N-m.
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