MOOG D664-4714 Servo Valve
June 05, 2026

MOOG D664-4714 Servo Valve

Product Overview D664-4714 belongs to MOOG D660 ServoJet two-stage high-flow servo proportional valve series, complying with ISO4401-08 NG25 standard installation dimension, equipped with built-in analog drive amplifier plus full-stroke LVDT spool closed-loop displacement feedback without external driver module. Model 4714 is factory pre-calibrated zero-lap four-way spring-centered spool configuration with customized flow gain tuning; standard NBR rubber sealing structure, separated internal T drain and independent external Y drain layout, adopting proprietary ServoJet jet-pipe pilot mechanism featuring superior anti-contamination performance to operate steadily under slightly contaminated hydraulic oil for metallurgical rolling and heavy-duty hydraulic test equipment.

Description

Model Code Definition

D664 = NG25 ISO4401 mounting footprint, ServoJet jet-pipe pilot, integrated onboard amplifier + full-range LVDT spool closed-loop feedback, large-flow D660 subfamily

4714 = Factory preset zero-overlap four-way spring-centered metering spool with exclusive optimized flow gain, null position fully calibrated at OEM workshop, standard amplifier circuit without customized K modification

Technical Specifications

Hydraulic Parameters

Rated Flow:478 L/min @35bar single-side differential pressure; peak instantaneous flow 1620 L/min @70bar supply differential pressure

Max Working Pressure:P/A/B main control ports up to 350bar; built-in T drain ≤210bar; external Y drain supports full 350bar working pressure

100% Full Stroke Step Response:≤27ms under rated 210bar supply hydraulic pressure

Control Precision:Hysteresis<0.24%FS, Resolution<0.068%FS, total thermal drift(-20~+80℃)<2.05%FS after factory gain fine-tuning

Null Leakage:0.26~1.82 L/min determined by original spool machining tolerance

Working Medium:Anti-wear mineral hydraulic oil, fluid cleanliness NAS6~7 / ISO4406 17/14/11, operating fluid temperature -20℃~+80℃

Net Weight:5.71kg

Electrical Parameters

Input Power Supply:24VDC wide voltage range(18~32VDC), static standby current ≤870mA

Default Control Signal:Factory standard ±10VDC differential analog input; ±10mA /4~20mA current signal optional via factory custom modification

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

EMC Standard:Conforms to EN55011 industrial electromagnetic compatibility regulation

Port & Connection Configuration

Hydraulic Interface:ISO4401 NG25 standard hole arrangement 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, unused X pilot port blocked with factory blank plug for non-external pilot oil application

Electrical Interface:11-pin circular receptacle integrates 24V power supply, ±10V command signal and full-travel 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 owns far stronger dirt resistance than traditional nozzle-flapper pilot, ensuring long-term continuous stable running under medium-impurity hydraulic fluid in metallurgical production workshops and test laboratories.

2.Optimized fixed flow gain of 4714 spool matches high-precision large-flow closed-loop control requirement; four-way zero-lap spool realizes accurate position/speed/force closed-loop adjustment for hot/cold rolling mill and heavy forging hydraulic cylinder; onboard LVDT automatically compensates spool drift induced by ambient temperature variation.

3.Spring-centered fail-safe neutral structure: main spool automatically returns to middle position upon power failure to cut off A/B oil circuit and lock hydraulic actuator, avoiding accidental equipment runaway damage.

4.Factory pre-calibrated built-in amplifier possesses outstanding anti-interference capability, adapting long-distance analog wiring under severe industrial field environment.

Typical Application

Hot & cold continuous rolling mill AGC roll gap closed-loop servo regulation, heavy slab hydraulic forging press master cylinder flow precise control, full-scale hydraulic component fatigue test bench, large aluminum/steel extrusion forming equipment, ship hydraulic servo test system.

Installation & Maintenance Instructions

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

2.Arrange power cable and shielded control wire inside independent wiring troughs to prevent inverter harmonic interference on analog control signal; fix valve with factory specified bolt torque and standard flat washers.

3.Flow gain and null offset parameters of standard 4714 version are fully pre-set at MOOG factory; only slight on-site potentiometer fine adjustment is permitted; complete disassembly of ServoJet pilot assembly and main spool component is strictly forbidden.

4.Seal spare unused 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.


Get a Quote