The energy-saving link of hydraulic excavator mainly lies in the hydraulic pump. Based on the different circuits of hydraulic pump, this paper discusses the energy-saving technology with quantitative and variable pumps.
1. Multi pump drive circuit. Single ration pump is the most basic pump in hydraulic system, and its application range is also greatly limited. If the operation requires multiple speeds and loads, its efficiency will be less than 35%. Therefore, compared with the hydraulic excavator with multi load and multi hydraulic, the drive circuit can save 50% power consumption.
2. Pressure matching hydraulic circuit. Compared with the ordinary circuit, the relief valve in the pressure matching hydraulic circuit can be used as a pressure compensation method in addition to eliminating the excess oil, which ensures that when the load changes, the inlet and outlet pressure difference of the throttle valve is a constant. From the perspective of energy saving, the working pressure of the hydraulic pump can automatically adapt to the load pressure. Moreover, it is higher than the load pressure from the beginning to the end, so as to improve the efficiency and reduce the loss.
3. Electro hydraulic load sensing system. The system can have a certain load sensing, the effect is to provide a good pressure to meet the load pressure, in order to effectively prevent excess pressure. Its principle is to transfer the fluctuating load pressure to the pressure compensation equipment.
4. Energy saving of accumulator. In the actual work, a large amount of oil will be needed suddenly. If a high-power engine is used to provide this demand, it will cause great waste. At the same time, the size of pipes, joints, hydraulic valves and oil tanks should be increased. The accumulator can effectively meet this demand and reduce energy consumption.
