What are the classifications of electro-hydraulic servo valves? How should I choose the right one?
Do you know what classification of electro-hydraulic servo valves? Dalan Motor tells you that you can distinguish according to the following six categories: 1. According to the classification of electromechanical converters: moving iron type and moving coil type; 2. Classification by hydraulic amplifier amplification series: single stage valve, two poles Valve and three-stage valve; 3. According to the structure of the pilot-stage valve, it is divided into: slide valve type, nozzle baffle type and jet tube type; 4. According to the power level main valve classification: zero position and main oil line port number ; 1 zero opening is divided into: positive opening (negative covering or negative overlapping) valve, zero opening (zero cover or zero overlap) valve and negative opening (positive covering or overlapping) valve. 2 The number of main oil passage ports is divided into three-way valve and four-way valve. 5. According to the feedback form, it is divided into: displacement feedback, force feedback, pressure feedback and electric feedback; 6. According to the output quantity classification, it is divided into: flow servo valve, pressure servo valve and pressure flow servo valve. After understanding the classification of electro-hydraulic servo valves, how should we choose the right valve? For details, refer to the following operations: 1. Electro-hydraulic servo valves are divided into single-stage, second-class and third-level. 1 Single-stage electro-hydraulic servo valve directly drives the spool valve spool by force motor or torque motor for systems with pressure less than 6.3MPa, flow less than 4L/min and small load change; 2 two-stage electro-hydraulic servo valve has two stages Hydraulic amplifier for systems with flow rates less than 200L/mm; 3 three-stage electro-hydraulic servo valves for greater flow and power output. 2. The servo valve should be selected according to the characteristics of the servo valve and the system performance requirements. 1 The biggest weakness of the servo valve is its poor anti-pollution ability. The particle size of the filter must be less than 3Î¼m. 2 Servo valve is used in closed-loop systems with high dynamic precision, high control precision and strong anti-interference ability. Proportional valves can be used for systems with dynamic accuracy requirements. 3. Considering the principle of response speed priority, the front stage of the servo valve preferentially selects the nozzle flapper valve, followed by the jet tube valve, and finally the slide valve. 4. From the power considerations, the jet tube valve pressure efficiency and volumetric efficiency are above 70%, should be selected first, then select the slide valve and nozzle flapper valve. 5. From the perspective of anti-pollution and reliability, the jet pipe valve has large diameter and strong anti-pollution ability, which can prolong the trouble-free working time of the system. 6. From the perspective of performance stability, the erosion of the jet tube valve is symmetrical, does not cause zero drift, stable performance and long life. 7. The opening form of the spool valve generally has a zero opening structure. 8. Servo valve specifications are determined by the power and flow of the system, and leave a flow margin of 15% to 30%. 9. The bandwidth of the servo valve is selected according to the bandwidth of the servo system 5 times to reduce the influence on the response characteristics of the system, but not too wide, otherwise the anti-interference ability of the system is reduced. ----- Responsible Editor: Dalan Oil Pump Motor 02- Purchasing Consultant Copyright http:/(Dalan Motor) Reprint, please indicate the source http://news.chinawj.com.cn