Moog Servo Valve Electro-Hydraulic Proportional Flow Control Valve with 290*180mm Size 1A Rated Current and 24V 220V Voltage

A MOOG Electro-Hydraulic Servo Valve is an electro-hydraulic conversion and power amplification component. Its primary function is to receive analog electrical control signals and then proportionally adjust the output flow and pressure of hydraulic fluid based on these signals, thereby achieving precise control of hydraulic actuators.

Most MOOG servo valves are two-stage valves. In the first stage, an electrical signal is sent to a torque motor, which moves a flapper between two nozzles, creating a pressure differential. This pressure difference acts on a spool (the second stage), moving it to control the main hydraulic flow to the load.

• High-Precision Control: They offer exceptional control accuracy, which can reach about 0.1%
• High Dynamic Performance: They feature fast response times, often in the millisecond range
• High Reliability and Stability: Designed with advanced technology and materials
• Variety of Designs: Available in various series to meet different performance needs
• Fail-Safe Functionality: Some models include a fail-safe feature

MOOG offers a comprehensive range of servo valves including:

• G761 Series: Two-stage flow control valve with mechanical feedback
• D630 Series (e.g., D634, D636, D637): Feature direct drive by a linear force motor
• D660, D661, D662 Series: Classic two-stage servo valves
• 72 Series: Standard response two-stage valves

• Maximum Operating Pressure: Up to 4000-4500 psi (approx. 31.5 MPa)
• Flow Control Range: From a few liters/minute to very high flows
• Input Signal: Typically a current signal (e.g., ±40 mA) or a voltage signal
• Coil Resistance: Typically in the range of 72-88 Ω
• Operating Temperature: -20°C to 80°C

• Industrial Machinery: Metal forming equipment, wood presses, plastic machinery
• Power Generation: Control of steam turbine valves, gas turbine fuel systems
• Test and Simulation: Automotive and aerospace test rigs, flight simulators
• Other Fields: Robotics, material handling

Common failures include:

• Torque Motor Issues: Broken coils, contamination in air gap
• Nozzle/Flapper Stage Issues: Clogged nozzles or orifices
• Spool Amplifier Stage Issues: Spool sticking, cutting edge wear

• Oil Filtration: Use high-quality filters and adhere to oil analysis schedule
• System Design: Minimize dead spots where contaminants can accumulate
• Regular Inspection: Check for leaks, unusual noises, or performance changes
• Preventive Maintenance: Follow manufacturer's recommended intervals