Description

The Woodward 9907-995 is a high-precision LQ25 liquid fuel metering valve designed for industrial gas turbine applications. It regulates the delivery of liquid fuel to the turbine combustor, transforming demand signals from the primary engine control system (such as a Woodward MicroNet or 723PLUS platform) into exact physical flow rates. Featuring an integrated dual-resolver feedback assembly, an internal ID module, and a 125 V DC Solenoid Operated Valve (SOV) with limit switch monitoring, this rugged valve assembly ensures deterministic, high-speed fuel orchestration required for demanding power generation and marine propulsion environments.

Commercial and Lifecycle Logistics

+---------------------------+------------------------------------------------------------+
| Parameter                 | Value                                                      |
+---------------------------+------------------------------------------------------------+
| Product Condition         | New Surplus (Original Factory Box) or Factory Remanufactured|
| Warranty                  | 12-Month Comprehensive Warranty                            |
| Availability              | In Stock / Ready for Immediate Global Dispatch             |
| Standard Lead Time        | 1–3 Business Days via DHL Express / FedEx / UPS            |
| Lifecycle Notice          | Product discontinued by OEM; repair, overhaul, and surplus |
|                           | stock remain highly viable for asset life extension       |
| Price Notice              | Price subject to market conditions; contact us for a firm  |
|                           | quote                                                      |
+---------------------------+------------------------------------------------------------+ 

Technical Specifications and Hardware Architecture

The 9907-995 is engineered to operate alongside specialized external digital valve drivers to control high-pressure liquid fuel paths with rapid step-response dynamics.

Valve Core and Flow Metrics

• Base Valve Architecture: Woodward LQ25 Series (Liquid Fuel Valve).
• Port Flow Area: 0.2 in^2 calibrated metering orifice window.
• Feedback Subsystem: Integrated 3-speed electrical resolver providing absolute position tracking of the valve stem.
• Driver Requirements: Requires an external digital actuator driver module to process position feedback loop dynamics and energize the electric motor.

Auxiliary Electrical Safety Interfaces

• Solenoid Operated Valve (SOV): Integrated 125 V DC emergency shutoff or bypass valve circuit.
• Position Feedback Verification: Equipped with a mechanical limit switch to provide hardwired diagnostic verification of fully closed or fully open statuses back to the safety PLC.
• ID Module: Contains an onboard identification chip that holds factory-calibrated flow characteristics and serial parameters, allowing the digital driver to automatically adapt to the specific valve assembly.

Mechanical and Environmental Robustness

• Enclosure Rating: High-grade corrosion-resistant stainless steel casting designed for marine and harsh coastal environment deployments (SST Marine classification).
• Thermal Envelope: Designed to handle severe industrial gas turbine enclosure temperatures; verify fluid thermal limits and ambient pressure profiles against the primary Woodward 35029 reference manual.

Field Integration and Upgrade Constraints

Critical Application Warning:

The Woodward 9907-995 relies on a 125 V DC coil configuration for its integrated Solenoid Operated Valve (SOV). Do not connect 24 V DC auxiliary trip power loops directly to these terminal blocks, as the lower voltage will lack the magnetic flux required to actuate the trip mechanism, rendering the safety interlock inoperable.

• Driver Matching: This specific model requires a matching digital driver core capable of parsing the 3-speed resolver signals and interacting with the onboard ID module. It cannot be driven by legacy analog current-loop valve amplifiers (such as older 4-20 mA servo-driver cards).
• Phasing Verification: During replacement commissioning, performing a comprehensive resolver phasing check is mandatory. Incorrect electrical phasing orientations on the resolver return lines can cause the digital actuator driver to misinterpret valve position, triggering immediate loop instability or overspeed trip blocks.
• Product Sunset Management: Because Woodward transitioned this liquid fuel valve family out of active production, ensure that spare replacement units are kept in an environment free of relative humidity to preserve the internal wound components, seals, and electrical connectors.

Frequently Asked Questions (FAQ)

What is the purpose of the 3-speed resolver inside the 9907-995 assembly?

The 3-speed resolver acts as a heavy-duty, brushless rotary transformer that tracks the mechanical stroke of the valve assembly. By using a multi-speed configuration, it provides exceptional resolution and micro-positioning feedback to the digital controller without the wear-and-tear liabilities of conventional resistive potentiometers.

How does the onboard ID module affect the installation process?

When matching a new or overhauled 9907-995 valve to an existing digital actuator driver, the driver queries the embedded ID module during power-up initialization. It uploads the unique factory calibration curves and port alignment parameters automatically, minimizing the need for extensive field-level flow trimming or manual calibration steps.

Can this unit be used for natural gas metering profiles?

No. The LQ25 series is engineered, sealed, and calibrated exclusively for liquid hydrocarbons (such as Diesel No. 2 or aviation grade kerosene). For gas-fired or dual-fuel turbine systems, a companion gas metering valve assembly—such as the Woodward GS6 or TecJet series—must be utilized in the fuel distribution skid.