1. Product Brief

2. Basic Information

• Brand: MOOG

• Model: D634-517

• Type: Pilotless electro‑hydraulic direct‑drive servo valve (DDV)

• Mounting: ISO 4401-05 (NG10)

• Drive: Permanent magnet linear force motor; no pilot oil

• Power Supply: 24 VDC (18–32 VDC); max 2.2 A

• Feedback: Integrated LVDT spool position closed‑loop

• Reset: Spring centering; failsafe to neutral on power loss

• Protection: IP65

• Weight: ~6.3 kg

• Connector: M18 6‑pin + PEMoog Inc.

3. Function & Positioning

• Core Function: Precision flow & direction control via analog signals; closed‑loop position/velocity/pressure/force control. Delivers ultra-low hysteresis, exceptional repeatability, and pressure-stable response.

• Positioning: High-flow, high-accuracy flagship model in the standard D634 series, for demanding industrial closed-loop hydraulics.

4. Core Performance Parameters

Hydraulic

• Max working pressure (P/A/B): 350 barMoog Inc.

• T‑port pressure: ≤50 bar (without Y); ≤350 bar (with Y)Moog Inc.

• Rated flow (Δp = 35 bar): 120 L/min

• Peak flow: ~220 L/min

• Null leakage: 0.2–1.8 L/min

• Fluid: ISO 11158 mineral oil

• Fluid temp: −20 °C to 80 °C

• Cleanliness: ISO 4406 17/14/11

Dynamic

• Full‑stroke step response: ≤10 ms

• −3 dB bandwidth: 80–100 Hz

• Hysteresis: <0.18% FS

• Resolution: <0.08% FS

• Temp drift (ΔT=55K): <1.2% FS

Electrical

• Standard control signal: ±10 VDCMoog Inc.

• Optional signals: ±10 mA, 4–20 mAMoog Inc.

• Spool feedback signal: 0–10 VDC

• Ambient temp: −20 °C to 60 °C

• Certification: CE compliant

5. Matching Accessories

• Shielded twisted‑pair signal cable; M18 waterproof connector

• ISO 4401-05 standard mounting manifold

• High‑precision hydraulic filter (≥10 μm)

• 24 VDC low‑ripple power supply (≥2.5 A slow fuse)

• Servo controller; displacement/pressure sensors

6. Application Fields

• Large‑scale hydraulic presses & forging machines

• High‑speed, high‑force injection molding & die‑casting

• Material fatigue & high‑frequency vibration test benches (heavy‑duty)

• Industrial closed‑loop motion control (high flow/power)

• Hydraulic simulation & load test systems (high‑capacity)