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Woodward 9908-202
Product Name: LQ25 Liquid Fuel Metering Valve (Standard Configuration)
Product Overview: 9908-202 is the baseline LQ25-series fully electric liquid fuel metering valve for industrial and aeroderivative gas turbines rated 1,000–42,000 kW. It couples an integrated brushless DC motor with a rotary shear-meter plate and a non-contact resolver feedback to deliver precise, repeatable fuel metering.
Detailed content
Key Technical Specifications:
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Applicable Power Range: 1,000–42,000 kW
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Maximum Fuel Inlet Pressure: 1,200 psig (8,274 kPa)
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Maximum Fuel Bypass Pressure: 100 psig (690 kPa)
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Nominal Metering ΔP: 50 psid (345 kPa)
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Minimum Metered Flow: 80 lb/h (36 kg/h)
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Turndown Ratio: >100:1
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Fuel Filtration: ≤20 µm
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Water Content: ≤0.1% by volume
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Solid Sediment: ≤1.0 mg/L
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Command / Feedback: 4–20 mA
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Drive Voltage: 18–32 VDC
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Full-Stroke Time: <100 ms
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Metering Accuracy: ±5% of nominal flow or ±0.5% of max flow (larger value applies)
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Weight: approx. 35 kg (77 lb)
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Nominal Bore: 29.2 mm (1.15 in)
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Ingress Protection: IP66
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Operating Temperature: –28 °C to +85 °C
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Storage Temperature: –40 °C to +103 °C
Functional Features: Single-moving-part rotary plate design, non-contact resolver (no mechanical wear), rare-earth PM motor for high torque density, remote emergency-shutdown input, valve/driver fault output. Self-cleaning shear metering resists contamination. No field calibration required—flow is factory-characterized.
Materials & Structure: Corrosion-resistant wetted materials, FKM seals, stainless steel internal hardware. Frameless single-speed resolver. Standard SAE threaded fuel ports, terminal-block electrical interface.
Working Principle: The driver converts the 4–20 mA command into motor current. The brushless DC motor rotates the metering sleeve, changing port area. The integral droop-compensated ΔP regulator holds 50 psid, making flow a direct function of port area.
Installation Requirements: Install on the discharge side of a positive-displacement pump. Keep bypass return line unobstructed. Use specified torque on standard fasteners. Ground shielded cable at a single point to prevent EMI. Position for easy inspection and maintenance.
Application Scenarios: Gas-turbine generator sets, industrial mechanical drives, marine propulsion liquid-fuel systems. Compatible with diesel, JP-series aviation fuel, kerosene, gasoline, and naphtha.
Usage Precautions: Maintain ≤20 µm filtration. Inspect electrical connections and cable insulation periodically. Wear hearing protection—the valve generates aerodynamic noise during operation. Avoid impact during transport/storage.
