Model Code Decoding

• D643: Base series, NG05 (ISO 4401-05) flow-only (Q) control DDV, high-flow industrial variant。

• 344:

  • 3: Rated flow 30 L/min (Δp=35 bar/land)

  • 4: Max pressure 350 bar (P/A/B ports)

  • 4: 4-way spool, linear, zero overlap, spring-centered, flow-only control

• (suffix omitted): Standard analog interface (±10 V), no fieldbus, firmware rev 1。

Technical Specifications

• Part Number: D643-344

• Valve Size: NG05 (ISO 4401-05, Cetop 5)

• Control Function: 4-way flow-only (Q) control, spring-centered (fail-safe: P→A, B→T on power loss)穆格中国。

• Rated Flow (Δp=35 bar/land): 30 L/min (±10%)

• Max Flow: 60 L/min

• Operating Pressure:

  • P/A/B ports: 350 bar

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

• Step Response (0→100%): ≤14 ms (210 bar

• Hysteresis: <0.2% (flow control)

• Linearity: <0.5%

• Electrical:

  • Supply: 24 VDC (18–32 VDC), 2.3 A ma

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

  • Feedback: LVDT (spool position, internal, closed-loop flow control)。

  • Protection: IP65 (mated connector)

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

• Temperature:

  • Ambient: −20°C to +60°C

  • Fluid: −20°C to +80°C

• Mass: ~7.9 kg

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

Interface & Communication Configuration

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

• Feedback: Integrated LVDT (spool position, closed-loop flow regulation)。

• Mounting: 4-hole NG05 (ISO 4401-05), M6 bolts, 12–14 Nm

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

Core Functions

1. 350 Bar High Pressure: For heavy-duty industrial hydraulic systems

2. 30 L/min Precise Flow: High-flow, low-hysteresis flow regulation for large actuators

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

4. Integrated Digital Electronics: Onboard flow controller, no external PLC required。

5. Fast Response: ≤14 ms step response, ideal for high-speed cyclic applications

6. Fail-Safe Spring Center: Safe position on power loss, ensuring system safety

Application Scenarios

• High-Pressure Flow Control: Hydraulic presses, metal forming, heavy machinery。

• Test Benches: Durability, vibration, and load testing (flow-controlled)。

• Plastics Machinery: Injection molding (high-flow, precise speed control)。

• Wood Processing: Sawmills, veneer presses (high vibration, contamination-prone environments)。

• General Hydraulics: High-pressure, high-flow dynamic flow control systems。

Compatibility & Differences

• Base Model: D643-344 = analog 30 L/min/350 bar 4-way flow-only DDV。

• vs D638-344: D638 = NG06 (smaller), p/Q control; D643 = NG05 (larger), flow-only穆格中国。

• vs D643-244: 244 = 20 L/min; 344 = 30 L/min (same pressure/flow function)

• vs D644-344: D644 = 210 bar (medium pressure); D643 = 350 bar (high pressure