Vickers SM4-20 Servo Valve | SM4-20(15)57-80/40-10-S182 | Two-Stage High Response

Vickers Type SM4-20 Series High-Performance Electro-Hydraulic Servo Valves

Product Overview: The Vickers SM4-20 Series is a benchmark in industrial precision control, featuring an advanced two-stage electro-hydraulic design. This series utilizes a highly sensitive nozzle-flapper pilot stage to drive a four-way sliding main spool. Through an internal mechanical feedback mechanism, the SM4-20 enables high-precision, high-dynamic closed-loop control of hydraulic flow. Its superior frequency response and low hysteresis make it the ideal choice for flight simulators, material testing machines, precision injection molding control, and high-performance hydraulic servo systems.

The featured model on this page is the SM4-20(15)57-80/40-10-S182, specially calibrated for stringent industrial feedback accuracy.

Key Technical Advantages:

• Superior Dynamic Performance: Features high-bandwidth frequency response, allowing for real-time tracking of microsecond-level command signal changes.

• Ultra-Low Hysteresis & High Resolution: Precision-ground spool and sleeve assemblies ensure minimal mechanical friction, keeping hysteresis at an extremely low level to significantly enhance positioning accuracy.

• Integrated Mechanical Feedback: The main spool position is linked back to the pilot stage via a feedback wire, ensuring exceptional null stability across varying pressure and temperature conditions.

• Rugged Reliability: Built with a robust valve body and contamination-resistant design (optimized for servo-grade performance) to ensure long service life in complex industrial environments.

Detailed Specifications & Parameters:

• Core Series: Vickers SM4 / SM4-20 Series.

• Full Model Code: SM4-20(15)57-80/40-10-S182.

• Core Performance Specs:

  • Nominal Size: Size 20 (Two-stage servo architecture).

  • Rated Flow: Range covering 57 L/min to 80 L/min (at standard pressure drops).

  • Operating Pressure: Rated up to 210 Bar (3000 PSI), with peaks reaching 315 Bar.

  • Control Command: Low-current servo drive signals (typically ±10mA, ±40mA, or ±200mA depending on coil configuration).

  • Feedback Type: Mechanical Feedback.

  • Design Sequence: 10 Series.