Semi-automatic spreaders are fixed to the hooks of gantry, bridge
and portal cranes. Twist lock control is carried out mechanically
by means of wire rope pulling. Hooking/unhooking is carried out
without help of crane workers. Simplicity and convenience of
spreader installation allow converting from hook crane into
container crane in a short time. There is no necessity to arrange
power supply for the spreader and to update the crane control
circuit.