2. A square threaded power screw is used for a machine tool. The screw has 75 mm external diameter and 12 mm pitch. The operating nut takes the axial load of 550 N on a flat surface of 70 mm and 1...
A single-square threaded 35-mm power screw is 35 mm in diameter with a pitch of 5 mm. A vertical load on the screw reaches a maximum of 5 kN. The coefficients of friction are 0.06 for the collar and 0.09 for the threads. The frictional diameter of the collar is 45 mm. Find the overall efficiency and the torque to "raise" and "lower" the load Repeat this problem if ACME screw is used in this design. A single-square threaded 35-mm...
4. A single-start, square-threaded power screw has the following baseline character- istics: Outside diameter pitch, p Load, W 25.4 mm 5.08 mm 1500 N thread friction coefficient 0.08 collar friction coefficient collar diameter 0.04 28 mm (a) What torque, TR, total, is required to raise the load? Include units. (b) What torque, TL, total, is required to lower the load? Include units (c) Suppose the screw runs at 100 rpm for ten seconds, raising the load. How much energy is...