Model Code Definition

D662 = NG16 ISO4401-07 installation specification, two-stage ServoJet jet-pipe pilot structure, built-in integrated amplifier servo valve base series

4930 = dedicated specification code defining fixed rated flow, zero-overlap linear spool profile, factory preset null offset, flow gain and dual T/Y drain fixed configuration.

Technical Specifications

Hydraulic Parameters

Rated Flow: 305 L/min at 35bar single metering land pressure drop; maximum bulk flow 510 L/min under 70bar supply differential pressure

Max Working Pressure: P/A/B main control ports rated 350bar; internal T drain permissible ≤50bar; standalone external Y drain withstands full 350bar working pressureMoog Inc.

Dynamic Response: Full stroke 0~100% step response ≤28.5ms at 210bar supply oil pressure

Control Accuracy: Hysteresis＜0.20%FS, Resolution＜0.08%FS, overall ambient thermal drift (-20℃~+55℃)＜2.4%FS

Null Leakage: 0.62~3.60 L/min

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

Net Weight: 3.90kg

Electrical Parameters

Input Power Supply: 24VDC wide range input (18~32VDC), quiescent no-load operating current ≤750mA

Standard Control Command: ±10VDC differential analog input; customized ±10mA or 4~20mA current signal available upon special orderMoog Inc.

EMC Standard: Compliant with EN55011 industrial electromagnetic compatibility standard; 7-pin military circular connector with IP65 protection grade.

Port & Electrical Configuration

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

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

Communication Mode: Pure analog closed-loop control, no embedded digital fieldbus communication interface.

Core Functions

Original ServoJet jet-pipe pilot design possesses superior anti-clogging capability compared with conventional nozzle-flapper pilot, ensuring stable long-cycle continuous operation under moderately contaminated hydraulic fluid in harsh workshop environments.

Internal integrated drive amplifier matches full-stroke LVDT closed-loop feedback circuit to automatically compensate temperature-triggered null drift, supporting non-stop 24-hour full-load continuous running.

Standard spring-centred neutral spool structure; spool mechanically returns to middle position once power supply fails to block A/B oil chambers and lock load position for equipment fail-safe protection.

Precision linear spool metering edge maintains constant flow gain, supporting seamless switching among closed-loop position, velocity and pressure control modes on single valve unit.

Typical Application

Heavy tonnage hot forging hydraulic press, automotive large-size sheet stamping line, steel strip hot mill tension regulation system, high-power multi-channel hydraulic fatigue test rig, oversized injection molding clamping hydraulic unit, aerospace composite thermal forming hydraulic equipment.

Installation & Maintenance Instructions

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

Route high-current power cables and shielded control wires inside separated wiring ducts to avoid frequency converter harmonic interference on analog control signals.

Null bias and flow gain parameters are fully pre-calibrated at factory; only minor onsite potentiometer fine adjustment allowed; complete disassembly of ServoJet pilot assembly and main spool group is strictly forbidden.

Seal all unused hydraulic ports with standard blank plugs during long-term spare storage; preserve inside dry dustproof warehouse to prevent rubber seal ageing and accidental oil leakage.