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Woodward 6945-673
Product Identification: Electro-Hydraulic Power Cylinder (EHPC) actuator, part of Woodward’s integrated linear actuator family configured for steam turbine control valve or valve rack positioning.
Product Overview: The 6945-673 belongs to Woodward’s EHPC series of application-specific, integrator-configured electro-hydraulic actuators. These units are custom-designed and built for each application, intended for driving steam turbine control valves or valve racks in industrial turbine systems.
Detailed content
Working Principle: The EHPC uses a low-pressure hydraulic oil source (typically 80–250 psi / 552–1724 kPa) and amplifies it through three amplification stages to produce the required output shaft force. It accepts an integrating input signal and converts it into precise linear shaft motion.
Technical Specifications:
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Supply Pressure: 80 to 250 psi (552 to 1724 kPa)
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Input Power: 24 Vdc ±10% @ 2 A
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Input Signal: 0–200 mA integrating input signal (100 mA null)
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Position Feedback: 4–20 mA, 20–4 mA, 0–10 Vdc, or 10–0 Vdc (minimum to maximum cylinder position)
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Output Shaft Diameter: 1.750 in (44.45 mm)
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Shaft Material: Hardened 17-4 PH stainless steel
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Thread Size: 1.250 in –12 UNF-2A
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Pressure Sensitivity: Not less than 2%
Application Scenarios: Steam turbine control valves, valve rack positioning, large industrial prime mover fuel/speed control linkages.
Installation Requirements:
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Must be mounted rigidly to the valve or valve rack assembly
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Hydraulic supply must be filtered and maintained within specified pressure range
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Electrical connections must be made per Woodward wiring diagrams for the specific configuration
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Static-sensitive; observe ESD precautions during handling and installation
Usage Precautions:
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Do not remove PCB from control cabinet unless absolutely necessary
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Avoid synthetic clothing to prevent static buildup; wear cotton or cotton-blend materials
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Do not touch PCB components or conductors except at edges
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Keep replacement PCBs in anti-static bags until installation
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Any unauthorized modification outside specified limits constitutes misuse and voids warranty
