As the core component of hydraulic control system, servo valve is widely used in industrial equipment with high precision and high response. Especially in the fields of large mechanical equipment, aerospace, heavy construction machinery, etc., the flow demand of hydraulic system is extremely high, so the application of “large flow servo valve” becomes particularly important. However, how to realize the effective flow of large-flow servo valve is a key issue in the design and application.
First, the basic principle of large flow servo valve
Servo valve is a kind of valve which can accurately control the flow and pressure in hydraulic system according to the input electrical signal. Its basic working principle is to control the electromagnetic torque motor through electrical signals, and then drive the valve core to move and change the opening of the throttle, so as to adjust the output flow and direction. On this basis, the large flow servo valve realizes the precise control of larger flow through structural optimization and material strengthening.
Second, the key technology to realize large flow.
1. Multi-stage amplification structure design
Most large-flow servo valves adopt “multi-stage” structure, that is, the combination of main valve and pilot valve. The pilot valve is responsible for receiving the control signal and driving the main spool, and the main spool controls the on-off and flow of the main oil circuit. This structure can effectively reduce the control force and realize the rapid response of large flow.
2. Optimize the flow channel design to reduce the pressure loss.
In order to improve the flow capacity, the flow channel inside the valve body must be optimized. Through CFD analysis, the local resistance and eddy current loss of the flow channel are reduced, thus improving the flow efficiency and reducing heat generation and energy consumption.
3. High performance materials and manufacturing technology
Under the condition of large flow, the valve core and valve body are subjected to great impact and wear, so it is necessary to use high-strength, wear-resistant and high-temperature resistant materials, and improve the service life and stability through precision machining and surface treatment.
4. Dynamic response and anti-interference ability are enhanced.
Large-flow servo valve is easily affected by hydraulic shock and load change in the process of flow passage, so it needs to be equipped with high-precision feedback device (such as LVDT displacement sensor) and adjust the position of the valve core in real time through closed-loop control algorithm to ensure stable flow output.
Iii. Matters needing attention in practical application
1. Reasonable selection
According to the maximum flow demand of the system, the servo valve with appropriate size is selected to avoid performance degradation or overload operation due to insufficient flow.
2. Matching of supporting systems
Large-flow servo valve often needs to be used in conjunction with high-pressure large-displacement pump, large-capacity oil tank and efficient cooling system to ensure the overall stability and reliability of the system.
3. Regular maintenance and monitoring
High-flow operation will aggravate the pollution of hydraulic oil and the wear of components, so the filter element should be replaced regularly, the wear of the valve core should be detected, and the condition monitoring technology should be used to warn the fault in advance.
IV. Conclusion
With the continuous improvement of industrial automation level, higher requirements are put forward for the response speed and power density of hydraulic system. As a key actuator in hydraulic system, the large flow servo valve has a direct impact on the overall performance of the system. Only through scientific design, advanced manufacturing technology and reasonable system matching can we truly realize the safe and efficient flow of large-flow servo valves and provide strong technical support for modern high-end equipment.