Question

A double square treaded power screw has the following specification:
Major diameter, 3 in.
Pitch, 0.2 in.
Coeffi cient of friction for collar, 0.16
Coeffi cient of friction for thread, 0.12
Frictional radius of the collar, 2.5 in
Input power, 3.5 hp
Velocity of the nut, 2.5 in/s
Calculate the overall efficiency of the power screw for raising the load?

(A) 0.05
(B) 0.10
(C) 0.15
(D) 0.20​

Answer 1

Answer:

double square treaded power screw has the following specification:

Major diameter, 3 in.

Pitch, 0.2 in.

Coeffi cient of friction for collar, 0.16

Coeffi cient of friction for thread, 0.12

Frictional radius of the collar, 2.5 in

Input power, 3.5 hp

Velocity of the nut, 2.5 in/s

Calculate the overall efficiency of the power screw for raising the load?

answer is 0.15