Hook rotation is often no signal occurred in the equipment hoisting homework, when hoisting machinery to lift heavy weights, hook spin, wear around the hook and boom top pulley block between the wire rope twisted together, the lift heavy weights also spin with hook, at this moment can not inherit lift or let go of have to lift heavy weights.
The lifting hook rotation affects the normal operation of the hoisting work, which seriously threatens the safety of the staff and equipment, so it must be avoided.
The causes of the lifting hook rotation are the internal and external factors of the crane, and the internal causes of the hook rotation are also the root causes.
Any type, specification, or number of wire rope used by the crane will generate torque when it is stressed.
The torque is caused by the way the wire rope is made, and the steel wire is twisted together to form a stock, and then several strands twisted together to form a wire rope.
When stressed, the steel wire and stock will be straightened, but the end of the wire rope is fixed when lifting the work, so the torque is formed inside the wire rope.
Another root formation of torque is wire rope in use after a period of time pitch longer, to make it in the cases, the fixed end of wire rope is not force, the torque and torque of the hook component has a tendency to rotate.
On the other hand, there are many external factors led directly to the hook, such as human or wind force to promote in the process of lifting hook, driver's operation instability that hook rotating hook and heavy swing and unbalanced hook way of wear around the hook to hook rotation, etc.