The power loss of excavator hydraulic system is mainly in the following five forms:
1.The throttling loss
Six-way multi-way valves are mostly used on hydraulic excavators as reversing and flow control components. In the process of adjusting the flow, a large amount of hydraulic oil is returned to the tank in the form of bypass and throttling, which causes the hydraulic system to power loss.
2.Overflow loss
When the pump output pressure exceeds the set pressure of the system safety valve, the system begins to overflow, causing power loss.
3.Overflow loss during the starting and braking of the slewing mechanism
In the hydraulic excavator slewing motor, a double-acting buffer valve (composed of two overflow valves) is usually set, which will open during the starting and braking process, causing overflow loss.
4.Potential energy loss and throttling loss during boom descent
The boom converts hydraulic energy into potential energy during the lifting process. In order to prevent the boom from falling too fast when descending, a one-way throttle valve is usually installed on the boom oil circuit to convert potential energy into heat energy for dissipation.
5.Loss caused by poor power matching between engine and hydraulic system
Due to the variability of the excavator's workload, the engine operating point is often located in an area with a higher fuel consumption rate, which means that the fuel energy is not fully utilized, causing losses.