A 12 hp motor is used to raise and lower a load W = 5000 lbf using a single threaded Acme screw(Course series-UNF) with a nominal major diameter of 1.5 inches that rotates during actuation asshown below. The coefficient of friction for the screw is f = 0.06 and friction due to the collar isnegligible f≈ 0.(a) The lead (1), the lead angle (2) and the mean diameter (dm)(b) Determine the rate in inches per second that the load can be raised and the torque required(T[lb-ft]) (rpm)to prevent overhauling of the screw. Note: hp=5252(c) Assuming a collar diameter of d = 1.75 in., what coefficient of collar friction (fc) wouldbe required to prevent overhauling and how much would this reduce the efficiency ofraising the load?(d) Determine the von Mises's stress at the thread root critical location during lifting of theload.W = 5000 lbfMotor

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shown below. The coefficient of friction for the screw is f = 0.06 and friction du negligible f≈ 0. (a) The lead (1), the lead angle (2) and the mean diameter (dm) (b) Determine the rate in inches per second that the load can be raised and the (T[lb-ft]) (rpm) to prevent overhauling of the screw. Note: hp = 5252 (c) Assuming a collar diameter of de = 1.75 in., what coefficient of collar fric be required to prevent overhauling and how much would this reduce th raising the load? (d) Determine the von Mises's stress at the thread root critical location durin load.

shown below. The coefficient of friction for the screw is f = 0.06 and friction du negligible f≈ 0. (a) The lead (1), the lead angle (2) and the mean diameter (dm) (b) Determine the rate in inches per second that the load can be raised and the (T[lb-ft]) (rpm) to prevent overhauling of the screw. Note: hp = 5252 (c) Assuming a collar diameter of de = 1.75 in., what coefficient of collar fric be required to prevent overhauling and how much would this reduce th raising the load? (d) Determine the von Mises's stress at the thread root critical location durin load.

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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