Mechanical Four-Ropes Clamshell Grab (MC4RC)

The advantages of a Two Rope Grab or Four Rope Grab hoisting mechanism with two ropes and two electric motors coupled by the planetary reduction gear adopted mechanism are multiple: (1) control of the mechanism is simple and synoptic and possibility of false engagement of the mechanism is practically excluded (2) possibility to close or open the grab in full speed of lowering, without previous stopping (3) smaller dimensions and smaller mass with respect to a mechanism with two independent electric motors and (4) avoidance of overload of grab carrying ropes.