Description
MOOG D635-671E
Technical Specifications
Brand: MOOG
Product Model: D635-671E
Product Type: Direct Drive Servo Valve (DDV) with Closed-Loop Spool Position Control
Series: D635 Series
Valve Type: 3-way, 4-way, or 2×2-way throttling control valve
Spool Drive: Permanent magnet linear force motor
Control Type: Closed-loop spool position control with integrated LVDT feedback
Supply Voltage: 24 V DC
Signal Input: 0 to 10 V
Rated Pressure (V-P, A and B ports): 350 bar (5075 psi)
Interface Standard: ISO 4401-03, CETOP 3 (NFPA D03)
Performance Level: S – Standard performance
Spool Type (Neutral Position): 2 – Closed center (all ports blocked) or 33 – P port closed, A and B to T
Spool/Spring Configuration: B – Spring centered, no solenoid; C – Spring centered, dual solenoid; F – Spring biased to port A
Configuration: L – Left-hand configuration (single solenoid) or blank – Standard right-hand configuration
Flow Rating (at Δp = 10 bar across P→A→B→T or P→B→A→T): 08 = 8 L/min (2 US gpm), 15 = 15 L/min (4 US gpm), 19 = 19 L/min (5 US gpm), 22 = 22 L/min (5.8 US gpm)
Throttle Condition: S – Outlet throttling only, A – Inlet throttling only, N – Inlet and outlet throttling
Manual Override: P2 – Standard manual override on both ends of single solenoid type; H – Waterproof manual override on solenoid end only; blank – Standard manual override on solenoid end only
Solenoid Identification: V – Solenoid identification determined by solenoid position; blank – Standard per ANSI B93.9
Electrical Connection: T – Terminal board; PA3 – 3-pin connector; PA5 – 5-pin connector
Coil Type: F – Flying leads and junction box; U – DIN 43650 connector; SP1 – Single 6.3 mm IEC-760 flat connector; SP1 – Dual 6.3 mm IEC-760 flat connector
Coil Voltage Rating: G – 12 V DC; H – 24 V DC; GP – Direct 12 V DC or EM-VP/VT amplifier; HA – Direct 24 V DC or EM-VP/VT amplifier
Amplifier Type: Current control
Tank Pressure Rating: 5 – 100 bar (1450 psi) for EN-427
Material: Stainless steel
Applicable Medium: Hydraulic oil
Operating Temperature: High temperature rated
Pressure Environment: High pressure
Functional Features
Direct Drive Design: Permanent magnet linear force motor directly drives the spool without requiring a pilot stage, eliminating pilot flow requirements
Closed-Loop Spool Control: Integrated LVDT position sensor provides real-time spool position feedback for precise closed-loop control
Pressure-Independent Dynamics: Direct drive design ensures dynamic performance is independent of system pressure variations
High Force Range: Linear force motor provides high output force, overcoming the unidirectional limitation of traditional proportional solenoid valves
Bidirectional Drive: Flexibly drives the spool in both directions from the spring-centered position
Low Current Consumption: Minimal current draw at hydraulic zero position and near-zero conditions
Integrated Electronics: Onboard circuit board with PWM drive circuitry and 24 V DC supply eliminates the need for external amplifiers
SMD Technology: Surface-mount device technology provides compact, reliable electronic integration
Fail-Safe Operation: Spool returns to spring-centered neutral position upon power loss, cable failure, or emergency stop
High Contamination Resistance: Built-in 10 μm filtration allows operation with NAS 6 cleanliness level hydraulic oil, extending maintenance intervals
Application Scenarios
Aircraft Flight Control: Primary flight control surfaces, engine thrust reversers, and landing gear systems
Industrial Machinery: Injection molding machines, metal forming presses, and test rigs requiring precise force and position control
Energy Sector: Wind turbine pitch and yaw control, hydroelectric turbine governors
Marine Applications: Ship steering systems, thruster control, and deck machinery
Automotive Testing: Vehicle suspension test rigs, engine test cells, and component testing
Aerospace Ground Support: Missile guidance actuators, radar positioning systems, and satellite testing equipment
Medical Equipment: Surgical robot actuators and patient positioning systems
Entertainment Industry: Motion simulation platforms and special effects actuators
