Winches
Effort force to raise a load.
A winch is a mechanical device that is used to wind up or wind out a rope or wire rope.
Velocity Ratio
The velocity ratio can be calculated as
VR = R / r (1)
where
VR = velocity ratio
R = effort force radius (m)
r = load radius (m)
Effort Force
The force to raise a load can be calculated as
F = W / (μ V R)
= W r / (μ R)
= m ag r / (μ R) (2)
where
F = force (N)
μ = mechanical efficiency of the system (equal to one for an ideal friction-less system, a fraction less than one for real-world systems with energy losses due to friction)
m = mass (kg)
ag = acceleration of gravity (9.81 m/s2)
W = weight (N)
Example - Winch Effort Force
The effort force for a winch with small radius 5 mm and large radius 10 mm, efficiency 0.95 and load 1000 kg - can be calculated as
F = (1000 kg) (9.81 m/s2) (5 mm) / ((0.95) (10 mm))
= 5163 N
Winch Calculator
