MOOG D633-308B Servo Valve
Product Overview
| Model |
D633-308B |
| Valve Type |
Direct-acting electro-hydraulic servo valve (DDV) |
| Valve Configuration |
4/3-way throttling type |
| Mounting Surface |
ISO 4401 Size 03 (NG6 / D03) standard |
Key Features
- Directly driven by linear force motor with built-in electronic amplifier
- Valve core position closed-loop feedback system
- Spring auto-centering for smooth actuator stop during power failure
- No pilot stage required - reduces leakage and system complexity
- Built-in PWM drive and position closed-loop electronic circuitry
Hydraulic Specifications
| Maximum Working Pressure |
350 bar (5000 psi) at P/A/B ports; T port ≤50 bar (up to 350 bar with Y-type connection) |
| Flow Rate |
Maximum flow rate: 75 L/min (19.8 gpm) at Δp = 35 bar |
| Response Time |
0–100% step response time ≤12 ms |
| Operating Temperature |
-20°C to +80°C (Standard FKM seal) |
| Compatible Media |
Mineral hydraulic oil, phosphate ester oil (Skydrol, etc.) |
| Recommended Cleanliness |
NAS 7/ISO 18/15 |
Electrical Specifications
| Power Supply |
24 VDC (18–32 VDC wide voltage compatibility) |
| Control Signal Options |
±10 V / ±10 mA / 4–20 mA |
| Electrical Interface |
Standard 6+PE pin connector (plug ordered separately) |
| Protection Rating |
IP65 (after installation and plug sealing) |
Performance Characteristics
- Extremely low hysteresis for precise control
- Excellent linearity across operating range
- Low threshold current requirements
- High repeatability for consistent performance
Physical Specifications
| Net Weight |
Approximately 0.9 kg |
| Gross Weight (standard carton) |
Approximately 1.2 kg |
| Dimensions |
Approximately 82 × 65 × 80 mm |
| Construction Materials |
Cast iron body / Cast aluminum, high-precision stainless steel valve core |
| Standard Seal |
FKM (fluororubber) - EPDM/FFKM upgrades available |