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Woodward 9908-209
Product Name: LQ25 Liquid Fuel Metering Valve with Pressurizing Valve (PIV)
Product Overview: 9908-209 adds a Pressurizing Valve (PIV) module to the standard LQ25 metering valve. The PIV raises downstream pressure above bypass pressure by 100 psig (690 kPa) or 200 psig (1,379 kPa), enabling accurate low-flow metering even when downstream manifold pressure is very low—ideal for peak-shaving power plants and vessels with frequent low-load transitions.
Detailed content
Key Technical Specifications:
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Configuration: LQ25 valve with PIV
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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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PIV Boost Setting: 690 kPa (100 psig) or 1,379 kPa (200 psig) above bypass pressure
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Minimum Metered Flow: 80 lb/h (36 kg/h)
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Fuel Filtration: ≤20 µm
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Water Content: ≤0.1% by volume
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Turndown Ratio: >100:1
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Drive Voltage: 18–32 VDC
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Command / Feedback: 4–20 mA
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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: Integrated PIV extends the precise-metering range into very low flows. Maintains metering accuracy despite downstream pressure fluctuations. Fully electric—no external hydraulic or pneumatic source. Self-cleaning self-cleaning shear metering. Factory flow-calibrated.
Application Scenarios: Gas-turbine systems requiring precise fuel control at low loads—peak-shaving power stations, part-load industrial drivers, and marine propulsion with frequent low-power transitions.
Working Principle: Same as the LQ25 baseline, with the PIV automatically regulating bypass flow to maintain elevated downstream pressure, preserving a predictable metering characteristic at low flows.
Installation & Usage: Identical to 9908-202, with particular attention to the PIV bypass line. Confirm the boost setting matches the engine fuel-system design.
