DESIGN OF CRANE HOOKS AND OTHER COMPONENTS OF LIFTING GEAR.

[Xekcted for publication, with written discusszon.] Most lifting gear components consist essentially of curved beams of very ductile material, the radius of curvature often being small in cornparison with the dimensions of the beam. In addition, in rings, chain links, etc., the distribution of bending moment is not directly calculable from the values of the applied loads, but is influenced also by the condition that the centre line of the section of the component must remain continuous when under load. The design of lifting gear components requires, therefore, the determination of the bending moments, etc., set up, the calculation of the stresses due to these bending moments, etc., 'and the consideration of the modification to the stress system consequent upon yielding in parts of the components. The effect of the curvature of the centre line of the component on the distribution of stress is first discussed, the method of calculation for differen