1. Basic Information (G631-3806B = D631-266C)

Structure: Dry torque motor + dual nozzle baffle pilot + four-way main valve core + mechanical feedback rod Moog China

Function: 4-way, zero opening, flow control (position / force / pressure closed loop) Moog China

Installation surface: ISO 4401-05 (Size 05) Moog China

Electrical interface: MS3106 aviation plug, single coil ±100 mA

Weight: Approximately 2.4 kg Moog Inc.

Material: Aluminum alloy valve body, nickel-based alloy valve core (corrosion-resistant / anti-corrosion)

2. Core Parameters (Δp = 35 bar / per side, standard condition)

Rated flow: 100 L/min

Maximum working pressure: 315 bar (4,500 psi)

Frequency response (−3 dB, 90° phase angle): ≈ 65 Hz Moog Inc.

Step response (100%): ≈ 22 ms Moog Inc.

Hysteresis: ≤ 3% (mechanical feedback) Moog Inc.

Resolution: ≤ 0.5% Moog Inc.

Internal leakage (zero position): < 4 L/min @ 315 bar Moog Inc.

Temperature range: Ambient -20 ℃ ~ +60 ℃; Oil -20 ℃ ~ +80 ℃ Moog Inc.

Filter requirements: NAS 6–7 grade (pilot small hole, medium anti-pollution) Moog Inc.

3. Model Meaning D631-266C

D631: 631 Series Two-stage Mechanical Feedback Servo Valve Mug China

266: Flow Code → 100 L/min @ 35 bar

C: Standard configuration, FKM seal G631-3806B

G631: MOOG Global Unified 631 Series Number

3806: Complete Specification Code (including flow / pressure / electrical / materials)

B: Version / Configuration (Steam Turbine / Power Generation Industry Standards)

IV. Key Features (G631-3806B Focus)

Heavy Machinery Feedback (MFB): Robust structure, long lifespan, heavy load stability, suitable for 24-hour continuous operation

High Flow + High Pressure: 100 L/min, 315 bar, covering heavy industry / power generation conditions

Steam Turbine Adaptation Enhancement: Valve Core Corrosion Resistant Alloy, Pilot Stage Anti-Vibration Optimization, Minimal Zero-Position Drift

Dry Torque Motor: Good insulation, resistant to oil interference, high reliability. MOOG China

External Amplifier: Standard ±100 mA, compatible with MOOG 100 Point or Third-Party Servo Amplifier

V. Typical Applications

Steam Turbine / Power Generation: Main Steam Valve, Control Valve, DEH Electro-Hydraulic Control (G631-3806B Main Model)

Heavy Materials Testing Machine, Large Fatigue Test Bench

Metallurgy: Large Rolling Mills, Roll Gap / Tension Control

Large Injection Molding / Blow Molding: Locking Force, Wall Thickness Control

Construction Machinery: Large Servo Actuator, Synchronous Lifting