Model Code Definition

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

4313 = Factory preset zero-overlap four-way spring-centered metering spool with fixed flow gain, null position pre-calibrated during original production

K = Custom modified amplifier version, gain & wide-temperature drift compensation optimized for cyclic variable heavy load of hot rolling & cold rolling mill, non-standard factory default amplifier setting

Technical Specifications

Hydraulic Parameters

Rated Flow:370 L/min @35bar single-side differential pressure; peak instantaneous flow 1390 L/min @70bar supply differential pressure

Max Working Pressure:P/A/B main ports rated 350bar; internal T drain ≤210bar; external Y drain full 350bar allowable working pressureMoog Inc.

100% Full Stroke Step Response:≤33ms under nominal 210bar supply hydraulic pressure

Control Precision:Hysteresis＜0.29%FS, Resolution＜0.08%FS, total thermal drift(-20~+80℃)＜2.4%FS after K-version circuit optimization

Null Leakage:0.33~1.98 L/min subject to factory 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:5.53kg

Electrical Parameters

Input Power Supply:24VDC wide input range(18~32VDC), quiescent standby current ≤910mA

Default Control Signal: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 assembly

EMC Standard:Compliant with 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, standard X pilot port blocked 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 provides superior anti-pollution property compared with conventional nozzle-flapper pilot, guaranteeing stable long-term continuous operation under medium contaminated hydraulic oil environment of metallurgical rolling workshop.

2.K customized amplifier effectively suppresses wide-temperature null drift; four-way zero-lap spool achieves high-precision closed-loop position/speed/force control for heavy-duty rolling mill; onboard LVDT dynamically compensates spool thermal deformation drift induced by ambient temperature fluctuation.

3.Spring-centered fail-safe neutral design: main spool automatically returns to middle position upon power failure to isolate A/B oil paths and lock hydraulic cylinder, preventing roller runaway damage of rolling equipment.

4.Factory pre-optimized fixed gain matching periodic fluctuating load of rolling production line; ±10VDC analog input features outstanding anti-interference performance for long-distance field wiring on metallurgical site.

Typical Application

Hot & cold rolling mill roll gap closed-loop servo control, strip thickness AGC automatic adjustment system of continuous metallurgical rolling line, large slab hydraulic compression equipment, heavy-duty metal forging press master cylinder precision flow regulation, large hydraulic component fatigue test bench.

Installation & Maintenance Instructions

1.Mount 3μm high-precision inline high-pressure 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 independent wiring ducts to avoid inverter harmonic interference to analog control signal; fix valve with factory specified bolt tightening torque and standard flat washers.

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

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