Model Code Definition

D664 = D660 high-flow subseries, NG25 ISO4401 installation dimension, patented ServoJet jet-pipe pilot + onboard amplifier + full-range LVDT spool closed-loop feedback

4039 = Factory-calibrated zero-overlap four-way metering spool with centering spring, fixed amplifier gain and null offset pre-set at original factory

No extended suffix = Standard NBR seal, split T/Y separate drain configuration, standard 11-pin circular aviation connectorMoog Inc..

Technical Specifications

Hydraulic Parameters

Rated Flow:360 L/min @35bar single-land differential pressure; peak instantaneous flow 1320 L/min @70bar supply differential pressure

Max Working Pressure:P/A/B main control ports rated 350bar; internal T drain ≤210bar; external Y drain full 350bar working pressure

Full Stroke Step Response:≤37ms under nominal 210bar supply hydraulic pressure

Control Precision:Hysteresis＜0.35%FS, Resolution＜0.095%FS, total thermal drift(-20~+80℃)＜3.0%FS

Null Leakage:0.40~2.15 L/min subject to factory spool machining tolerance

Working Medium:Mineral anti-wear hydraulic oil, fluid cleanliness NAS6~7 / ISO4406 17/14/11, working fluid temperature -20℃~+80℃

Net Weight:5.48kg

Electrical Parameters

Input Power Supply:24VDC wide input range(18~32VDC), static standby current ≤930mA

Default Control Command:Factory standard ±10VDC differential analog input; ±10mA /4~20mA current signal available via factory customized modificationMoog Inc.

Connector:11-pin circular aviation receptacle, IP65 protection after complete cable wiring assembly

EMC Compliance:Conforms to EN55011 industrial electromagnetic compatibility specification

Port & Connection Configuration

Hydraulic Interface:ISO4401 NG25 standard hole layout including P supply port, A/B actuator control ports, separated built-in T internal drain and dedicated Y external drain; pre-installed original NBR mounting gasket from factory, standard X pilot port sealed with factory plug for non-external pilot oil setup

Electrical Interface:11-pin circular socket integrates 24V power supply, ±10V command signal and full-range LVDT feedback wiring; double-shielded control cable required with single-point cabinet grounding, no fieldbus communication function.

Core Functions

1.Patented ServoJet jet-pipe pilot delivers better anti-pollution performance versus conventional nozzle-flapper pilot, enabling long-term steady continuous operation under moderately contaminated hydraulic fluid environment.

2.Medium-flow customized four-way zero-lap spool achieves high-precision closed-loop regulation for position, speed and force control on heavy-duty hydraulic systems; onboard LVDT closed-loop dynamically offsets spool dimension drift induced by wide-range ambient temperature variation.

3.Spring-centered fail-safe neutral design: main spool automatically returns to middle position upon power loss to isolate A/B oil passages and lock hydraulic cylinder for mechanical safety protection.

4.Factory optimized fixed amplifier gain matched for medium-load continuous running condition; ±10VDC analog input owns outstanding anti-interference for long-distance wiring precision closed-loop control.

Typical Application

Medium-tonnage hydraulic forging press master cylinder servo control, metallurgical cold rolling mill roller fine positioning system, medium-size aluminum die-casting machine clamping & injection closed-loop regulation, hydraulic component durability fatigue test bench flow adjustment, offshore auxiliary hydraulic loading test equipment.

Installation & Maintenance Instructions

1.Install 3μm high-pressure inline precision filter on upstream P supply pipeline; replace filter cartridge after first 15 working days of equipment commissioning startup.

2.Arrange power cable and shielded control wire inside separated wiring ducts to avoid inverter harmonic interference to analog command signal; mount valve with factory specified bolt tightening torque and standard flat washers.

3.Flow gain and null offset parameters are fully pre-calibrated at MOOG factory; only minor on-site potentiometer fine-tuning permitted; complete disassembly of ServoJet pilot unit and main spool assembly is strictly prohibited.

4.Block unused spare T/Y drain ports with original factory blank plugs during spare part storage; store valve in dry dustproof warehouse to prevent NBR rubber seal ageing and subsequent oil leakage.