Lifting a One Tonne Load

The crane will need to be able to lift a 1000kg load and move it 4m, with no guaranteed source of electricity the only source of power will be manual. For a small group of people, the one tonne load can be easily managed using a pulley system as mentioned under ‘Pulley Design’. Even with a 6 to 1 pulley system a two person team will need to each move the equivalent of 83.3kg by 6m to raise the load just 1m off the ground, that’s almost the same as carrying a person up a single flight of stairs. Using a winch, the turning force generated can be multiplied to reduce the effort a 5th of the original work needed.

The winches available on the market will vary from the design shown so the force that will need to be applied will also vary. The calculations are based in an ideal situation and in reality they will be much greater. Factors such as friction, temperature, humidity, strength of the individuals and the elasticity of the cable will need to be accounted during the second design phase.