question archive A screw jack with a 1-in
A screw jack with a 1-in
Subject:Electrical EngineeringPrice: Bought3
A screw jack with a 1-in. double-thread Acme screw is used to raise a load of 10,000 lb. A plain thrust collar of 2.0 in. mean diameter is used. Coefficients of running friction are estimated as 0.13 and 0.10 for f and fc, respectively. (See Figure P10.6.)
(a) Determine the screw pitch, lead, thread depth, mean pitch diameter, and helix angle.
(b) Estimate the starting torque for raising and for lowering the load.
(c) Estimate the efficiency of the jack when raising the load.
