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What are the advantages and features of grab cranes? During operation, the function of the traveling mechanism of a grab crane is to guide the vehicle along its tracks; it allows the entire weight of the vehicle to be transferred to the rails. The grab mechanism ensures that the vehicle moves along the tracks with minimal resistance, thereby enabling it to pass through curves smoothly. When a grab crane is operating continuously, the temperature of its hydraulic oil does not rise too high. The reason for this is that, during the process of grabbing cargo, the grab may become stuck, or the grab cylinder may reach its intended position; in the case of a fixed-displacement pump, the displacement of the oil pump remains constant. When a grab crane experiences a situation where the load gets trapped during lifting, the hydraulic oil will effectively flow out through the relief valve. Prolonged leakage of oil in this manner results in a rapid increase in the temperature of the hydraulic oil, which keeps rising further. In the hydraulic system of a grab crane, if the oil temperature is too high, it accelerates the aging of seals and oil hoses. If the oil temperature in the equipment is extremely high, the grab will operate unstably. If the pressure cannot be maintained, the equipment will fail to hold onto the cargo. The system-set working pressure of the grab crane is higher than that set for the variable displacement pump system, which thereby increases the gripping force of the grab. The bearing used in the grab’s shaft is a maintenance-free type, making the maintenance of the grab more convenient. When the grab crane’s motor starts, its system is in a unloaded state; therefore, the motor starts under no load. As a result, the starting current of the motor is much lower than that of a motor operating under load, which provides some protection for the electrical components during use.