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Woodward 9904-665
Product Name: 3171 Gas Valve with TM-55 Electrohydraulic Actuator Assembly
Product Introduction: This assembly combines the 3171 rotary sleeve gas metering valve with the TM-55 actuator’s high-response electrohydraulic servo system, achieving fast and precise control of gas flow. The assembly is suitable for gas turbines and engine applications with high control accuracy requirements.
Detailed content
Technical Specifications:
- Valve Type: Rotary sleeve gas metering valve
- Maximum Travel: 45°
- Gas Working Pressure: 0 to 600 psia (0 to 4,137 kPa) standard; 0 to 900 psia (0 to 6,206 kPa) optional
- Gas Flow Range: 25 to 20,000 lb/h (11 to 9,072 kg/h)
- Hydraulic Supply Pressure: 400 to 1,000 psig (2,758 to 6,895 kPa)
- Design Pressure: 750 psig (5,171 kPa)
- Burst Pressure: 2,500 psig (17,238 kPa)
- Actuator Type: TM-55 electrohydraulic actuator
- Output Shaft: 0.750″-48 serrated shaft, 0.875″ length
- Torque Motor: Dual-coil nozzle-type servo valve
- Null Current: 20 mA (10 mA per coil when parallel)
- Full Scale Current: ±140 mA (±70 mA per coil when parallel)
- Position Accuracy: 600°/second (bidirectional)
- Bandwidth: >5 Hz
- Operating Temperature: -40°C to +149°C
- Vibration: 10G max, 0 to 2,000 Hz
- Shock: 20G max
- Weight: Approximately 42 kg (assembly)
- Hazardous Area Certification: Class I, Division 1, Groups C & D
Functional Features: High-precision resolver position feedback directly coupled to the valve metering shaft; adjustable minimum/maximum mechanical limits to prevent overtravel; internal mechanical feedback delivering excellent open-loop accuracy; dual-coil design supports redundant or parallel operation; valve and actuator are calibrated as an integrated assembly, with characterization curve data file provided from the factory.
Application Scenarios: Dry Low Emission (DLE) combustion control; industrial gas turbine fuel metering; aeroderivative gas turbines; power generation and mechanical drive units.
Material Composition: Valve body in stainless steel; actuator housing in anodized aluminum; internal parts in hardened stainless steel; static seals in Viton (fluoroelastomer); dynamic seals in unfilled PTFE (Teflon).
Structural Features: Rotary sleeve gas metering valve with TM-55 electrohydraulic actuator; high-precision resolver directly coupled to the metering shaft; adjustable mechanical limits; dual-coil torque motor servo valve.
Working Principle: The electronic control system outputs current to the torque motor, driving the nozzle deflection to generate a differential pressure, which pushes the second-stage spool to control the flow direction of high-pressure oil to the double-acting servo piston. The piston’s linear motion is converted through internal linkage into output shaft rotation, which in turn rotates the valve sleeve to regulate gas flow. The resolver provides real-time valve position feedback, forming a closed-loop control.
Installation Requirements: Hydraulic oil filtration precision of 10 μm (nominal); the supply system must be equipped with an accumulator to handle transient flow demands; pipeline connection via 1″ 600 lb ANSI B16.5 flange; electrical interface 0.75 NPT (for resolver).
Usage Precautions: Maintain hydraulic oil cleanliness to the specified 10 μm nominal filtration; ensure supply pressure stays within 400 to 1,000 psig; avoid impact loads on the output shaft; regularly inspect the hydraulic oil and filter status.
