Vickers Type SM4 Servo Valve | SM4-20(15)57-80/40-10 | SM4-12 | High Dynamic Control

Vickers Type SM4 Series Two-Stage High-Response Servo Valves

Product Overview: The Vickers SM4 Series is recognized as a premier solution for high-performance electro-hydraulic control in industrial and aerospace simulation sectors. Utilizing a sophisticated two-stage design—a sensitive nozzle-flapper pilot stage and a four-way sliding spool output stage—this series converts micro-electrical signals into high-power, precise hydraulic commands. It is specifically engineered for closed-loop systems requiring exceptional frequency response, low hysteresis, and stringent linearity, such as flight simulators, precision machine tools, and hydraulic test rigs.

Featured prominently are the precision models SM4-20(15)57-80/40-10 and the compact high-frequency variant SM4-12(2.5)9-80/40 10-S72.

Key Technical Advantages:

• Superior Dynamic Bandwidth: Offers industry-leading frequency response, tracking control signals within milliseconds to ensure fluid and instantaneous actuator movements.

• High Resolution & Low Hysteresis: Precision-ground spool and sleeve assemblies minimize mechanical friction, keeping hysteresis typically below 3% for micron-level positioning.

• Integrated Mechanical Feedback: The spool position is linked back to the pilot stage via a mechanical feedback wire, providing a robust physical closed-loop that enhances null stability and disturbance rejection.

• Rugged Reliability: The valve body is built to withstand extreme mechanical vibration and high-temperature conditions, compatible with both aircraft hydraulic fluids and standard industrial mineral oils.

Detailed Specifications & Parameters:

• Core Series: Vickers SM4 High-Response Servo Series.

• Featured Model Matrix:

  • SM4-20(15)57-80/40-10 (Size 20, Rated flow approx. 57-80 L/min)

  • SM4-12(2.5)9-80/40 10-S72 (Size 12, Specific sequence for customized flow/feedback characteristics)

• Core Performance Specs:

  • Nominal Sizes: SM4-10, SM4-12, SM4-20 (from compact precision to medium power output).

  • Max Operating Pressure: Rated up to 210 Bar – 315 Bar (3,000 – 4,500 PSI).

  • Control Command: Low-current input signals (typically ±8mA, ±10mA, or ±40mA).

  • Filtration Requirement: Critical; system cleanliness must meet NAS 5 / ISO 16/13 or better.

  • Design Sequence: 10 Series, 30 Series.