Model Code Decoding

• D638: Base series, NG06 (ISO 4401-03) pressure/flow (p/Q) control servo valve。

• 216:

  • 2: Rated flow 20 L/min (Δp=35 bar/land)Moog Inc.。

  • 1: Max pressure 210 bar (P/A/B ports)Moog Inc.。

  • 6: 4-way spool, linear, zero overlap, spring-centered, p/Q control (pressure + flow limiting)。

• 0001: Standard analog interface (±10 V), no fieldbus, firmware revision 1。

Technical Specifications

• Part Number: D638-216-0001

• Valve Size: NG06 (ISO 4401-03, Cetop 3)。

• Control Function: 4-way p/Q (pressure + flow) control, spring-centered (fail-safe: P→A, B→T on power loss)。

• Rated Flow (Δp=35 bar/land): 20 L/min (±10%)Moog Inc.。

• Max Flow: 40 L/minMoog Inc.。

• Operating Pressure:

  • P/A/B ports: 210 barMoog Inc.。

  • T port: 50 bar (std) / 350 bar (Y-port option)。

• Step Response (0→100%): ≤10 ms (210 bar)Moog Inc.。

• Hysteresis: <0.2% (pressure control)。

• Linearity: <0.5%。

• Electrical:

  • Supply: 24 VDC (18–32 VDC), 1.2 A max。

  • Command: ±10 V (std); ±10 mA / 4–20 mA optional。

  • Feedback: LVDT (spool position, internal) + integrated A-port pressure transducerMoog Inc.。

  • Protection: IP65 (mated connector)。

• Fluid: Mineral oil (DIN 51524), viscosity 5–400 mm²/s。

• Temperature:

  • Ambient: −20°C to +60°C。

  • Fluid: −20°C to +80°C。

• Mass: ~2.7 kg。

• Seals: FPM (Viton, high-pressure std) / NBR (option)。

Interface & Communication Configuration

• Electrical Interface: Analog ±10 V command + 24 VDC; no fieldbus (0001)。

• Feedback: Integrated LVDT (spool position) + A-port pressure sensor (closed-loop p/Q control)Moog Inc.。

• Mounting: 4-hole NG06 (ISO 4401-03), M5 bolts, 8–10 Nm。

• Porting: P, A, B, T; Y-port available (high backpressure)。

Core Functions

1. 210 Bar Medium Pressure: For standard industrial hydraulic systemsMoog Inc.。

2. 20 L/min Precise p/Q: Balanced flow + closed-loop pressure regulation for medium actuators。

3. Direct-Drive Design: No pilot oil, pressure-independent dynamics。

4. Integrated Digital Electronics: Onboard p/Q controller, no external PLC requiredMoog Inc.。

5. Fast Response: ≤10 ms step response, low hysteresis/non-linearityMoog Inc.。

6. Fail-Safe Spring Center: Safe position on power loss。

Application Scenarios

• Medium-Pressure Force/Pressure Control: Hydraulic presses, clamping systems。

• Test Benches: Fatigue, vibration, and component durability testing (force-controlled)。

• Machine Tools: High-speed, accurate hydraulic actuators with pressure limiting。

• Plastics Machinery: Injection molding (clamp force control)。

• General Hydraulics: Medium-pressure, dynamic pressure + flow control systems。

Compatibility & Differences

• Base Model: D638-216-0001 = analog 20 L/min/210 bar 4-way p/Q valve。

• vs D638-206-0001: 206 = 350 bar; 216 = 210 bar (lower pressure rating)Moog Inc.。

• vs D636-213-0001: D636 = flow-only; D638 = p/Q (pressure + flow) control。

• vs D639-216-0001: D639 = NG10 (Size 05), higher flow (40–100 L/min)。