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Woodward 8915-712
- Product Name: 3103 Gas Fuel Metering Valve complete with TM55 Electro-Hydraulic Actuator
- Product Introduction: The Woodward 8915-712 is a factory-configured package consisting of a 3103 rotary sleeve-and-shoe gas fuel metering valve driven by a TM55 electro-hydraulic actuator. This combination is designed for industrial gas turbines in the 5000–50,000 hp (3730–37,300 kW) range, delivering precise fuel flow scheduling for acceleration, deceleration, and closed-loop control of shaft speed, torque, and gas temperatures/pressures.
Detailed content
- Technical Specifications:
- Maximum natural gas flow: 7,500–50,000 lb/hr (3,405–22,700 kg/hr)
- Minimum flow setting: as low as 50 lb/hr (22 kg/hr)
- Flow turndown ratio: up to 500:1
- Maximum inlet pressure: 45 bar (650 psig)
- Operating temperature: –40 to +250 °F (–40 to +121 °C)
- TM55 minimum valve slew time: 100 ms; time constant: 25 ms
- TM55 shearing force at sleeve OD: >300 lbf (1,334 N)
- Functional Features: Self-cleaning metering sleeve and seal shoe; through-hardened stainless steel shoe scrapes deposits off the sleeve as it rotates; high working force levels for contaminant resistance; actuator rate limiting available in the increase-flow direction.
- Application Scenarios: Heavy-duty industrial gas turbines; oilfield generator and compressor drives running on contaminated or sour gas; gas turbine fuel control systems requiring high-reliability fuel metering.
- Performance Parameters: Maintains accuracy and dynamic response through a 30,000-hour overhaul interval; operates reliably in sour gas environments with hydrogen sulfide, organic acids, sand, rust, and water contamination.
- Material Composition: Stainless steel valve housing; through-hardened stainless steel metering sleeve and seal shoe with hard surface coatings; corrosion-resistant design throughout.
- Structural Characteristics: Rotating metering sleeve with a cut-through metering port; spring- and pressure-loaded seal shoe against the sleeve; guide tube provides smooth flow path directing heavy contaminants through the metering port; converging flow path with no dead space or corners.
- Working Principle: Gas enters through the guide tube, passes through the metering port whose open area is determined by the sleeve position. The TM55 actuator rotates the sleeve based on demand signals from the electronic control system, adjusting the effective port area to regulate fuel flow. The self-cleaning action occurs as the shoe scrapes deposits from the sleeve during rotation.
- Installation Requirements: Read the entire 3103 Installation and Operation Manual before installation; mount the valve and actuator as a complete assembly; ensure hydraulic power unit supply meets TM55 requirements; orient the actuator per Woodward’s outline drawings; connect resolver feedback wiring per manual; install a 25-micron absolute inline gas filter upstream; verify flow direction matches system design.
- Usage Precautions: Do not operate outside the specified mechanical, electrical, or hydraulic limits — unauthorized modification constitutes misuse and voids warranty. Maintain gas cleanliness: solid particles <10 µm at ≤30 ppm, >10 µm at ≤0.3 ppm. Regularly inspect hydraulic pressure and oil condition. Avoid overpressure, overtemperature, or rapid thermal shock. Inspect electrical connectors for sealing integrity and resolver feedback signal stability. Follow Woodward OEM-recommended maintenance intervals; return the actuator to Woodward for overhaul at the prescribed interval.
