SX4 Servovalves Series

Introduction

Vickers SX4 servovalves provide closed loop control with exact positional accuracy,repeatable velocity profiles, and predictable force or torque regulation.Compared to Vickers SM4 servovalves,the SX4 offers extended frequency response and improved stability in closed loop systems.

Typical applications include plastic injection molding and blow molding systems,test  and  simulation equipment,die casting machines, hydrauic  press  brakes,animation  and    entertainment equipment,oil exploration vehicles,and lumber machinery.

The four models in the extended frequency response SX4 series offer a wide range of rated flows from 3,8 to 761/min(1.0 to 20 USgpm)at △p of 70 bar(1000  psi).

The SX4 is a two-stage,modular design,flow control valve which can be manifold or subplate mounted.The symmetrical,dual coil,quad air gap torque motor mounts to the first stage   nozzle flapper valve with six screws for better stability in high shock environments.An integral 35 micron absolute filter reduces sensitivity to contamination of the first stage.The second stage utilizes a four-way sliding spool and sleeve arangement with a mechanical null adjust.Spool position is  fed back to the first stage by means of a mechanical spring. 

An SX4 servovalve can be used with a hydraulic cylinder,position transducer, and electronics for infinite cylinder position control to within 0,025 mm (0.001 in)or better,depending on component selection,length of stroke,and load characteristics.When applied with servo hydraulic motors, tachometers,and electronics,the  SX4 provides infinite proportional flow control for real-time velocity/acceleration profiles that can be closed loop error corrected to within one-tenth of a revolution per minute.With appropriate pressure transducers or load cells, cylinders,and electronics in force control applications, the SX4 offers exact load pressure/force contro and excellent system stability with pressure to±0,07   bar(±1   psi)and   load   to±1% full scale.

The field-proven design of the SX4   servovalve,combined with Vickers   precision manufacturing techniques, provides you with the optimum in system control.

Features and Benefits

● The extended frequency response of the Vickers SX4 servovalve makes it the best competitive choice across a full range of applications.

●Each size of the extended frequency response SX4 is available in both standard response and high response models.The high response models offers enhanced system bandwidth for critical performance requirements.

● The wide range of SX4 fow capabilities allows selection of the valve size best suited for an application.

● The high strength aluminum alloy of the second stage valve body means lighter weight with rugged durability.

● The SX4-20 is also available with a special stainless steel body and end caps for operating pressures up to 350  bar (5000psi).

● The symmetrical,dual-coil,quad air gap,dry torque motor in Vickers servovalves,with its extremely fast  response to input signals,results in highly accurate control profiles.

● The SX4's exclusive jeweled feedback ballreceiver virtually eliminates the wear that can lead to loss of control across nullin other servovalves.

●An improved null adjust provides smoother,more precise adjustment.

●Jeweled orifices greatly extend the life of the valve.

●An integral 35 micron filter provides extrafirst stage contamination protection.

● The spool and sleeve are hardened stainless steel to minimize wear and erosion.The sleeve is mounted with O-rings to eliminate spool binding and ensure smooth operation.

●Customized spool lap and sleeve   porting are available to provide the specific flow control required for special applications.

● The SX4's symmetrical design provides inherenly dependable metering of control flow and minimum null shifts.The result is more consistent machine operation.

●Viton*seals  are standard.

● The flexibility of standardized port circles,mounting   patterns,and adapter manifolds makes Vickers servovalves a cost effective choice for replacing existing servovalves and enhancing existing systems

● The SX4-20 is available with an optional pilot pressure port that allows either additional first stage filtration or the use of externa pilot pressure for freedom   from supply pressure fluctuations.

● The SX4 features a simple interface to an available dual filter module that provides extra protection against system contamination.

Operating Data

Flow and Leakage

All data is typical, based on actual tests at 70 bar (1000 psi) ∆p, 30 cST (141 SUS), and 49°C (120°F).