The 6 machines in service [which show 'drift'] have regular proof tests and rope examinations. Torque from ropes is minimise by left hand and right hand lays. Tension meters are also used to ensure equal loading and grapple level . The Techs are very skilled at rope replacement / adjustment...
I am dealing with a waste container handling crane. Waste container is 12000kg. It is lifted by a grapple by twist locks at each corner. Height of lift is 14m. The contents of the container leads to an offset c of g which cannot be avoided. The containers are to be stacked 6 high.
The crane...