This series of electric - hydraulic slewing cranes can be of various types of marine vessels selected for lifting goods, spare parts, food use; the overall structure of the machine is divided into the base unit, rotary devices and boom three parts. The motor direct drive pump for pressure oil passes through the hydraulic system to the executing agency to complete the cargo lift. Used for lifting, rotation and amplitude movements, all carried automatic protection device, the device and active force control system has nothing to do, if for some reason have lost power or loss of pressure, all the action will automatically stop, to ensure the safety of crane systems and personnel .