Model Code Definition

D664 = NG25 ISO4401 installation dimension, ServoJet jet-pipe pilot structure, onboard amplifier + full-travel LVDT spool closed feedback, large-flow D660 subdivision

Z = Factory customized special spool profile and modified internal amplifier parameter vs standard D664 base model

4306 = Pre-calibrated zero-overlap four-way spring-centered metering spool with dedicated flow gain setting, null point fully factory trimmed

K = Intrinsically safe (IS) explosion-proof electrical variant, modified coil & amplifier circuit to meet intrinsic safety standard for explosive hazardous location applicationMoog Inc.

Technical Specifications

Hydraulic Parameters

Rated Flow:395 L/min @35bar single-side differential pressure; peak instantaneous flow 1310 L/min @70bar supply differential pressure

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

Full Stroke Step Response:≤27.5ms under nominal 210bar supply oil pressure

Control Precision:Hysteresis＜0.22%FS, Resolution＜0.062%FS, overall thermal drift(-20~+80℃)＜1.95%FS after customized factory gain calibration

Null Leakage:0.20~1.65 L/min subject to 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:5.82kg

Electrical Parameters

Input Power Supply:24VDC wide range(18~32VDC), intrinsic safety limited standby current ≤790mA (lower than standard non-K version for explosion protection)

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

Connector:11-pin explosion-proof circular aviation socket, IP65 ingress protection after cable assembly, IS-certified wiring terminal design

EMC & Safety Standard:Conforms to EN55011 EMC and intrinsic safety explosion-proof specification for Class I hazardous locationMoog Inc.

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-mounted original NBR mounting gasket, unused X pilot port blocked with factory blank plug for non-external pilot oil usage

Electrical Interface:11-pin IS explosion-proof circular receptacle integrates 24V restricted power, ±10V command signal and full-travel LVDT feedback wiring; double-shielded intrinsic safety control cable required with single-point cabinet grounding, no fieldbus communication function, must connect with approved IS safety barrier for explosive site installationMoog Inc.

Core Functions

1.Patented ServoJet jet-pipe pilot features superior contamination resistance compared to conventional nozzle-flapper pilot, ensuring continuous stable operation under medium-impurity hydraulic fluid in harsh industrial and hazardous explosive working sites.

2.Z+4306 customized spool flow gain satisfies medium-large flow high-precision closed-loop regulation; four-way zero-lap spool realizes precise position/speed/force control for rolling mill AGC gap and heavy forging cylinder; onboard LVDT automatically compensates temperature-induced spool zero drift.

3.Spring-centered fail-safe neutral design: main spool automatically returns to middle position upon power loss to shut off A/B oil path and lock hydraulic actuator to avoid unexpected equipment runaway damage.

4.K intrinsic safety modification limits internal circuit maximum voltage/current below explosive ignition threshold, safe for flammable gas & dust environment; factory pre-calibrated customized amplifier delivers outstanding anti-interference performance for long-distance analog wiring in severe electromagnetic fieldMoog Inc.。

Typical Application

Petrochemical industry hydraulic test rig, hazardous-site metallurgical hot/cold rolling mill AGC roll gap servo adjustment, explosion-proof heavy hydraulic forging equipment, chemical extrusion forming hydraulic system, oil & gas field hydraulic actuator closed-loop controlMoog Inc.。

Installation & Maintenance Instructions

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

2.Power cable and IS shielded control wire must be routed inside independent explosion-proof wiring troughs to avoid inverter harmonic interference; fix valve with factory specified bolt torque and standard flat washers; mandatory install certified intrinsic safety barrier between control cabinet and valve for explosive area deploymentMoog Inc..

3.Flow gain and null offset parameters of Z4306K variant are fully preset at MOOG factory; only slight on-site potentiometer fine-tuning allowed; complete disassembly of ServoJet pilot assembly and main spool unit is strictly forbidden, especially prohibited altering internal IS circuit components.

4.Seal idle spare T/Y drain ports with original factory blank plugs during spare part storage; store valve in dry dustproof non-explosive warehouse to prevent NBR rubber seal ageing and oil leakage; K explosion-proof version cannot replace with non-K standard model in hazardous location.