What is the top of the crane hook
That is, the limit switch is not working. The hook has been raised to the top of the reel.
Top: lifting hook over the winch. It is not entirely correct to say that it is not the right thing to bump into a boom or pulley, because your problem is a crane, not a bridge or a car tireCause: upper limit position limiter (upper limit) failure or damage.Hazard: may break the wire rope, hook head down, may also crush the pulley. Equipment accident or personal injury accident. Most of the top is a single beam electric hoist
That is, the hook rises, the travel switch fails, the hook has been to the upper body, the single beam is hit the drum, and the double beam is hit the pulley block
The lifting of the crane hook means that the hook rises over the limit and hits the suspension arm pulley block. There are two reasons: 1. from the lifting end, the limit switch failed, 2. from zero to zero, the brake failed, and one of the reasons will cause the impact.
[top] crane hook level of tower crane jib truck trolley for collision with the trolley bottom to prevent the lifting hook up to the highest position, lifting height limiter is arranged on the lifting mechanism, GB5031 tower crane "5.6.1.2" provisions of tower crane trolley, hook up to the top of the device the minimum distance of the lower end of the small frame of 800mm, should be able to immediately stop the lifting movement, but due to falling movement. In the actual operation process of tower crane, lifting height limiter is failure, the driver failed to timely stop hook upward movement, it will form at the top of the lower part of the frame hook device with small collision (also called top), lifting wire rope for hoisting and often pulled off the hook with lifting weights from falling, the consequences are very serious, because the hook hoisting hoisting wire breakage caused by hook falling accidents have occurred in the construction site. There are several reasons for the top:1, crane after a long period of operation of internal parts will occur, such as the relaxation of the upper limit of the screw. When the limiter is loose, the screws on it cannot touch the retainer better.2, because each device has its own service life. If you do not check it on time, the long-term accumulation of the device to limit the potential for more hidden, leading to the occurrence of roof.3, if the joint limiter without sticking occurred lax. Once the limiter fails, it will lead to the top of the hook.4, due to the installation of the crane, the staff did not modulate the order of the controller. At this time, the contacts of the limiter will be hidden, and the top of the case will be produced.5, even if there is no problem in the installation, in the use of still have to pay special attention to. Some of the wrong operation will cause the top.
