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Composition of a crane: A crane consists of a drive mechanism, a working mechanism, a lifting device, a control system, and a metal structure. By manipulating the control system, the driving device converts power energy into mechanical energy, transmitting force and motion speed to the gripping device. The gripping device connects the material to be handled with the crane, and through the separate or combined movements of its working mechanisms, it carries out the task of transporting the material. Movable metal structures connect the various components into a single unit, and bear the weight of the crane itself as well as the load it lifts. 1. Drive device: The drive device is the power equipment used to operate the working mechanism. Almost all track cranes, elevators, lifts, etc. are powered by electricity. Mobile cranes that can move over long distances (truck cranes, wheel cranes, and crawler cranes) are mostly powered by internal combustion engines. Human power drive is suitable for some small lifting equipment, and it is also used as an auxiliary drive for certain devices as well as for temporary power in case of accidents. 2. Working mechanisms: The lifting mechanism, running mechanism, luffing mechanism, and rotating mechanism are known as the four main mechanisms of a crane. Cranes achieve the purpose of moving materials through the independent movement of a certain mechanism or the combined movement of multiple mechanisms. The lifting mechanism is a device used for the vertical lifting of materials, and it is the most important and fundamental mechanism in a crane. As long as there is a lifting mechanism, that mechanism can be called a lifting equipment. The running mechanism is used to achieve horizontal transportation of materials. Some operating mechanisms are used solely to adjust the working position of the crane. The luffing mechanism is a device that changes the working range by adjusting the length and elevation angle of the boom. The rotating mechanism allows the boom to rotate around the crane’s vertical axis, enabling the crane to transport materials within a circular space. The luffing mechanism and the rotating mechanism are specialized working mechanisms unique to boom cranes. 3. Loading device: Different types of loading devices are used depending on the type, shape, and size of the materials to be lifted. Finished items are often lifted using hooks and eyelets ； For example, bulk materials such as grain, ores, and fertilizers are commonly picked up using grabs or hoppers ； Liquid materials are stored in containers such as cylinders and tanks. For special materials, special lifting devices are often used; for example, crane beams are employed to lift long-shaped materials, electromagnetic cups to lift ferromagnetic materials, rotating hooks to lift steel coils, as well as lifting devices designed specifically for containers. Preventing the dropped load from falling and ensuring the safety of the operators as well as protecting the load from damage are the basic safety requirements for lifting devices. 4. Control System: The control system includes various controllers, displays, as well as related components and wiring; it is the interface through which the human-machine safety requirements of cranes are manifested. Through electrical and hydraulic systems, the crane operator can control the movement of the crane, ensuring the smooth progress of lifting operations and preventing accidents. 5. Metal structure: The metal structure is an important component of cranes. It is the framework of the entire crane, combining its various components into a cohesive unit and creating a certain working space; it also bears the various loads acting on the crane as well as its own weight. The collapse and failure of metal structures can have extremely severe, even catastrophic, consequences for cranes. The significant difference between cranes and other ordinary machines is that cranes have a large, movable metal structure, with multiple mechanisms working together. Cranes are characterized by periodic intermittent operation cycles, uneven lifting loads, inconsistencies in the movement cycles of their various components, and asynchronous loading on these components. Moreover, crane operations require the participation and coordinated effort of multiple people, all of which increase the complexity of such tasks. Even when operating under normal conditions, the crane and its surrounding area can become hazardous zones, posing significant challenges for safety measures.