Model Code Decoding

• D634: Series, ISO 4401‑05 (NG10) size

• Z: High‑flow 4‑way configuration (enhanced flow paths)

• 10: Rated flow 100 L/min (Δp=35 bar/land)

• 38: Special revision 38 (customized firmware, enhanced diagnostics, extended temperature range)

Technical Specifications

• Part Number: D634Z1038

• Valve Size: ISO 4401‑05 (Size 05 / NG10)

• Control Function: 4‑way flow control, spring‑centeredMoog Inc.

• Rated Flow (Δp=35 bar/land): 100 L/min (±10% tolerance)

• Max Flow: 180 L/min

• Operating Pressure:

  • P/A/B ports: 350 bar (5,000 psi)

  • T port (without Y): 50 bar; (with Y): 210 barMoog Inc.

• Response Time (0→100% step): ≤20 ms

• Hysteresis: <0.2%

• Null Shift (ΔT=55 K): <1.0% (improved vs standard 20/22 versions)

• Electrical:

  • Supply: 24 VDC (18–32 VDC), 3.0 A max

  • Signal: ±10 V, ±10 mA, or 4–20 mAMoog Inc.

  • Connector: 6+PE (EN 175201), IP65 (mated)

• Fluid: Mineral oil (DIN 51524), viscosity 15–100 mm²/sMoog Inc.

• Temperature:

  • Ambient: −30°C to +70°C (extended range)

  • Fluid: −20°C to +85°C

• Mass: ~7.9 kgMoog Inc.

• Seals: FPM (standard for high‑temp compatibility)Moog Inc.

Interface & Communication Configuration

• Electrical Interface: Analog command (±10 V / ±10 mA / 4–20 mA) + 24 VDC powerMoog Inc.

• Feedback: Integrated spool position sensor (closed‑loop control); enhanced diagnostics output (fault codes via analog signal)

• Mounting: 4‑bolt ISO 4401‑05 pattern (M6 screws, 11–13 Nm torque)Moog Inc.

• Porting: P, A, B, T; optional drain Y (for T > 50 bar)Moog Inc.

Core Functions

1. High‑Flow 4‑way Design: Optimized for 100 L/min rated flow, suitable for large‑bore actuators

2. Direct‑Drive Linear Motor: No pilot flow, high force, pressure‑independent dynamicsMoog Inc.

3. Integrated Closed‑Loop Control: Onboard electronics for spool position feedback, high accuracyMoog Inc.

4. High Dynamic Response: ≤20 ms step response, ideal for fast high‑flow positioning/force control

5. Enhanced Diagnostics: Revision 38 adds fault detection (overtemp, short circuit, null drift) with analog output alerts

6. Extended Temperature Performance: Wider ambient/fluid temperature range for harsh industrial environments

7. Low Null Shift: Improved thermal stability (<1.0% null shift) for precision applications

Application Scenarios

• Industrial Machinery: Large injection molding, die‑casting, heavy‑duty metal forming pressesMoog Inc.

• Test & Simulation: Large‑scale flight simulators, high‑force vibration test benchesMoog Inc.

• Hydraulic Actuation: High‑precision control of large‑bore hydraulic cylindersMoog Inc.

• Harsh Environment Systems: Outdoor/extreme‑temperature industrial hydraulic systems

Compatibility Note

• Series Compatibility: Interchangeable with D634Z 60/80/100 L/min models and standard D634 4‑way valves

• Key Difference (38 vs 20/21/22 Version):

  • Version 20: Standard null performance

  • Version 21: Improved thermal stability, lower null shift

  • Version 22: Enhanced EMC, better noise immunityMoog Inc.

  • Version 38: Extended temperature, enhanced diagnostics, FPM seals, ultra‑low null shift

• Replacement: Drop‑in upgrade for lower‑flow D634K series or pilot‑operated high‑flow servo valves