Description
Woodward 8516-039
Technical Specifications
- Brand: Woodward
- Part Number: 8516-039
- Product Type: Electro-Hydraulic Linear Actuator
- Control Signal: Typically 4-20mA or servo valve drive signal
Functional Features
- High Force Output: Generates substantial mechanical force to overcome high fluid pressures and valve friction.
- Precise Positioning: Provides highly accurate, linear stroke control with minimal hysteresis.
- Fail-Safe Design: Incorporates internal spring-return mechanisms to drive the valve to a safe position upon loss of hydraulic pressure or power.
Application Scenarios
Deployed in steam turbine stop valves, gas turbine fuel control valves, and critical pressure regulation systems.
Performance Parameters
- Dynamic Response: Fast step-response to accommodate rapid load changes or emergency trips.
- Positioning Accuracy: Exceptional repeatability for stable process control.
Material Composition
Housed in a rugged cast iron or steel cylinder with precision-machined internal spools, high-performance seals, and corrosion-resistant coatings.
Structural Characteristics
Features a cylindrical industrial profile with integrated LVDT (Linear Variable Differential Transformer) for position feedback and high-pressure hydraulic ports.
Working Principle
An electrical command signal directs a pilot servo valve to route high-pressure oil into the actuator cylinder. The resulting piston movement is continuously monitored by the LVDT and fed back to the controller for closed-loop regulation.
Installation Requirements
Mechanically link to the control valve with precise alignment to prevent binding. Ensure hydraulic supply lines are properly filtered.
Usage Precautions
Never exceed the rated hydraulic supply pressure. Bleed all air from the hydraulic lines before commissioning to prevent spongy operation.
