Model Code Definition

D662 = NG16 ISO4401-07 installation dimension, two-stage ServoJet jet-pipe pilot construction, built-in integrated electronic drive servo valve base series

4884 = unique specification code including fixed rated flow, zero lap linear spool profile, factory preset null bias and flow gain parameters, dual drain (inner T + outer Y) fixed configuration.

Technical Specifications

Hydraulic Parameters

Rated Flow: 270 L/min at 35bar differential pressure per single metering land; peak flow 465 L/min under 70bar supply differential pressure

Max Working Pressure: P/A/B main control ports 350bar; built-in T internal drain ≤50bar; standalone Y external drain rated up to 350barMoog Inc.

Dynamic Response: Full stroke 0~100% step response ≤27.8ms under 210bar supply pressure

Control Accuracy: Hysteresis＜0.19%FS, Resolution＜0.08%FS, overall thermal drift (-20℃~+55℃)＜2.3%FS

Null Leakage: 0.58~3.45 L/min

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

Net Weight: 3.86kg

Electrical Parameters

Input Power Supply: 24VDC wide voltage input (18~32VDC), static no-load operating current ≤730mA

Standard Control Command: ±10VDC differential analog input; optional ±10mA /4~20mA current control upon customized order

EMC Compliance: Conforms to EN55011 industrial EMC standard; 7-pin military circular connector with IP65 ingress protection gradeMoog Inc.

Port & Communication Configuration

Hydraulic Interface: Standard ISO4401-07 NG16 mounting hole layout, P supply port, A/B actuator control ports, internal T drain port, independent external Y drain port

Electrical Interface: 7-pin military circular receptacle integrating power supply, analog command signal and full-travel LVDT feedback wiring; double-shielded control cable with single-point grounding at control cabinet terminal

Communication Mode: Pure analog closed-loop regulation, no digital fieldbus communication interface equipped

Core Functions

Patented ServoJet jet-pipe pilot design delivers far better anti-pollution performance compared with conventional nozzle-flapper pilot, ensuring long-term steady continuous running under moderately contaminated hydraulic fluid in severe industrial working environments.

Embedded drive amplifier cooperates with full-stroke LVDT closed-loop feedback circuit to automatically compensate temperature-induced null drift, supporting 24-hour nonstop full-load continuous operation.

Standard spring-centered neutral spool construction; spool automatically returns to central position once power fails to lock A/B oil cavities and fix load position for equipment fail-safe protection.

Optimized linear metering spool edge maintains stable flow gain, enabling flexible switching among closed-loop position, velocity and pressure control modes on single valve body.

Typical Application

Large hot forging hydraulic press, automotive heavy sheet metal stamping production line, steel wide-strip hot rolling mill tension control system, high-capacity multi-channel hydraulic fatigue test bench, large-tonnage injection molding machine clamping hydraulic unit, aerospace composite hot forming hydraulic equipment.

Installation & Maintenance Instructions

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

Separate high-power power cables and shielded control wires into independent wiring troughs to avoid frequency converter harmonic interference against analog control signal.

Null offset and flow gain parameters are fully factory pre-calibrated; only slight on-site potentiometer fine-tuning is permitted; complete disassembly of ServoJet pilot module and main spool assembly is strictly forbidden.

Seal all unused hydraulic ports with dedicated blank plugs during long-term spare part storage; store inside dry dustproof warehouse to prevent rubber seal aging and unexpected oil leakage.