Oil supplementing and flushing hydraulic system for closed hydraulic driving loop of multi-shaft engineering machinery

The invention provides an oil supplementing and flushing hydraulic system for a closed hydraulic driving loop of a multi-shaft engineering machinery, which comprises a closed hydraulic motor, first and second throttling orifices, first, second, third, fourth, fifth, sixth, seventh, eighth, ninth and tenth oil ways, a one-way replenishing valve, a pressure alarm switch, an electric fan cooler, first, second and third one-way valves, a gear pump, an energy accumulator, a closed hydraulic pump, a prime motor, a filter and an overflow valve. Compared with a conventional structure, the system ensures that the pressure on the low pressure side is still not lower than the value of a reversing spring of the one-way replenishing valve when the low pressure side in the closed loop is under the limited condition of excessive leakage through the reversing spring of the one-way replenishing valve, the energy accumulator and the one-way valve and can performing flushing and cooling on the pump and the motor by using cold hydraulic oil and control the maximum flushing flow of the pump and the motor by the throttling orifices so as to improve the working efficiency and fault tolerance and safety of the system.