The group crane electric hoist loss accident refers to the sudden drop of goods during the lifting operation, and the heavy objects are dropped from high altitude so as to have a significant impact on the construction safety. Therefore, we should make good management and preparations to prevent dangers in advance. Mechanical accidents are more common and mostly more serious. We need to prevent it in advance. There are mainly the following types of group hoist fall accidents: the first chain breaking accident, the main reason for the hoisting and breaking of the chain is mostly due to overload lifting; the failure of the hoisting limit switch causes over-breaking Chain; due to long-term use and lack of maintenance caused by rust or deformation, wear and tear, etc. to meet or exceed the scrap standard, not to be replaced and continue to use and other reasons caused breakage accidents. The second category is broken hook accidents, which are usually caused by the loss of heavy objects caused by broken hooks. The cause of the broken hook accident is basically the defective material of the hook. The hook has reached the end of the scrap limit due to long-term wear and tear, but it is still used or often overloaded, causing fatigue damage and fracture damage. Most of the lost accidents of group hoist electric hoist machines also occur in the reel winding system of the lifting mechanism. In addition to decoupling, chain breaking and hook breaking, the fixing of both ends of each lifting chain is also very important. Is the fixing and wedge fixing structure safe? reasonable. In addition, the accident of chain grooving and wheel chucking will also lead to accidents of loss. The third category is the rope-off accidents, which are accidents in which heavy objects fall off the bundled hoisting ropes, resulting in accidental casualties and destruction. The main reason for the rope-off accident is that the operator's binding method and method of the heavy object are improper, causing the heavy object to slip off; secondly, the operator's lifting center of gravity is not properly selected, the partial load lifting occurs or the heavy object falls off due to the instability of the lifting center; Being swayed by collision, impact, vibration, etc., causing heavy objects to be lost. The fourth category is decoupling accidents. Uncoupling accidents are accidents caused by heavy objects, lifting ropes or special spreaders coming out of hook hooks and dropping objects. Most of the reasons for the decoupling accidents are the lack of hook protection devices for the hooks; the failure of the protection function of the hook protection devices; the improper lifting method and the excessive opening caused by the deformation of the hook hooks

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