Product Details:

MOOG D631-333C two-stage servo valve belongs to MOOG D631 series, it is a precision flow control valve complying with ISO4401 size 05 mounting standard, designed for high precision closed-loop hydraulic motion control systems. This servo valve adopts polarized dry torque motor, double nozzle-flapper pilot stage and cantilever mechanical spool feedback structure. The torque motor converts analog electrical command signals into flapper deflection, forming pressure difference to drive the main spool, adjusting hydraulic oil flow rate and direction to precisely control the position, speed and force of hydraulic cylinders and actuators. The spool and sleeve assembly is processed by ultra-precision grinding, featuring low hysteresis, good linearity and excellent repeatability. The cantilever mechanical feedback stabilizes spool position and delivers fast dynamic response for fatigue test and simulation applications.

This high dynamic flow component maintains stable working performance under high rated pressure, continuous mechanical vibration and fluctuating ambient temperature. It responds rapidly to incoming control signals and keeps minimal control deviation. MOOG D631-333C two-stage servo valve is widely used in static and dynamic material fatigue testing machines, aerospace hydraulic simulation test benches, heavy metal forming presses, metallurgical rolling production lines and automated hydraulic manufacturing machinery.

The nozzle-flapper pilot stage is sensitive to hydraulic fluid contamination. Regular hydraulic oil inspection and filter replacement are essential. Fine solid particles suspended in hydraulic fluid will scratch the nozzle and precision matching surfaces of spool and sleeve, leading to internal leakage and control drift. Every MOOG D631-333C flow regulator undergoes complete factory performance tests before shipment, including flow characteristic curve test, frequency response test and internal leakage inspection. Strict quality control ensures stable and repeatable precision for closed-loop hydraulic control applications.

Specifications:

Brand: MOOG

Model: D631-333C

Product category: Two-stage electro-hydraulic servo valve

Drive principle: Polarized dry torque motor, double nozzle flapper with cantilever mechanical feedback

Mounting standard: ISO4401 size 05

Feature: Fast dynamic response, low hysteresis, high resolution, precise flow regulation

Application: High precision closed-loop hydraulic system, material test machine, metal forming press, aerospace test bench

Working medium: Fully filtered industrial hydraulic oil

Working environment: Industrial site with vibration and temperature variation