Description
Woodward A8516-040
Technical Specifications
- Speed Setting Range: Fully adjustable across the operating range.
- Drive Rotation: Counterclockwise.
- Output Torque: High-torque rotary output for direct valve actuation.
- Safety Device: Integrated Overspeed Test Device (OTSD) for ATEX environments.
Functional Features
- Independent Operation: Generates its own hydraulic pressure via an integrated shaft-driven oil pump.
- Mechanical Speed Sensing: Uses a centrifugal ball head assembly to directly measure turbine speed.
- Steam Flow Modulation: Translates mechanical speed errors into precise rotary valve movements.
- Fail-Safe Design: Purely mechanical operation ensures control during power loss.
Application Scenarios
Widely deployed in industrial steam turbine applications driving centrifugal pumps, air compressors, and standalone electrical generators.
Performance Parameters
- Control Type: Mechanical-hydraulic speed droop control.
- Response: Direct mechanical linkage ensures rapid, fail-safe response.
- Safety Compliance: OTSD mechanism allows reliable overspeed testing in classified environments.
Material Composition
Durable TG-17 die-cast aluminum housing with precision-machined steel internal hydraulic components.
Structural Characteristics
- Form Factor: Compact, self-contained mechanical module.
- Mounting: Flange-mounted directly to the turbine gearbox or casing.
- Interfaces: Mechanical input drive shaft and rotary output terminal shaft.
Working Principle
The governor is driven by the turbine’s input shaft, spinning the internal ball head assembly. Centrifugal force alters the ball head position, shifting the hydraulic pilot valve to direct oil pressure to the rotary output shaft, adjusting the steam control valve to restore target speed.
Installation Requirements
- Securely bolt to the turbine with precise shaft alignment.
- Correctly couple the rotary output shaft to the turbine’s steam valve linkage.
- Ensure drive shaft rotation matches the counterclockwise specification.
Usage Precautions
- Regularly test the integrated OTSD for overspeed protection functionality.
- Maintain clean hydraulic oil to prevent pilot valve sticking.
- Inspect mechanical linkages for wear or looseness during maintenance.
