Model Code Definition

D662: NG16 mounting standard, ServoJet pilot structure, integrated onboard drive electronics series

4127: Flow specification code; rated flow = 1400 L/min at ΔP=35bar per metering land, higher than D662-4124 (1340L/min); internal T drain plus separate external Y drain layout. Standard part suffix D02HYABN6VSF3-A, O-spool center configuration, NBR elastomer seal, ±10V differential analog command, 7-pin circular military connector, full-travel LVDT spool feedback, matched pilot valve D061-9327Moog Inc..

Technical Specifications

Hydraulic Parameters

Rated Flow: 1400 L/min @ 35bar pressure drop across single spool land; max approximate flow 2470 L/min at 70bar differential pressure

Max Working Pressure: 350 bar for P/A/B main ports; internal T return ≤50bar; external Y drain rated for 350bar

Dynamic Response: Full stroke 0~100% step response ≤30.5ms under 210bar supply pressure

Control Accuracy: Hysteresis <0.2%FS, Resolution <0.1%FS, total thermal drift within -20℃~+55℃ <2.35%FS

Null Leakage: 0.8~3.95 L/min

Working Medium: Mineral-based anti-wear hydraulic oil; recommended fluid cleanliness NAS 6~7 / ISO4406 17/14/11; operating fluid temperature -20℃ ~ +80℃

Net Weight: 3.92kg

Electrical Parameters

Power Supply: 24VDC (wide range 18~32VDC), static current draw ≤730mA

Standard Control Command: ±10VDC differential analog input; optional ±10mA or 4~20mA analog signal versions available

EMC Compliance: EN55011 industrial standard; connector protection grade IP65Moog Inc..

Port & Connection Configuration

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

Electrical Interface: 7-pin circular military receptacle integrating power, control signal and LVDT feedback wiring; double-shielded control cable with single-point earthing at control cabinet

Control Type: Pure analog closed-loop control, no industrial fieldbus communication interface.

Core Functions

ServoJet jet-pipe pilot design provides superior contamination resistance versus conventional nozzle-flapper pilot, enabling stable long-term operation under poor oil quality in metallurgical & forging harsh environments.

Built-in LVDT full spool closed-loop plus onboard amplifier automatically compensates null shift induced by ambient temperature variation, supporting 24/7 continuous full-load operation.

D02 O-center spool: springs center spool upon power loss to lock A/B actuator chambers for load holding, complying with machine safety stop requirement.

Optimized oversized internal flow channel ensures excellent linear flow gain; single valve supports seamless switching among position, velocity and pressure closed-loop control modes.

Typical Application Fields

Heavy plate hot rolling mill AGC hydraulic downforce system, ten-thousand-ton multi-directional open-die forging press, giant horizontal cold-chamber die-cast high-speed injection unit, high-power marine hydraulic test bench, oversized carbon fiber hot-press forming equipment, heavy-duty multi-channel high-frequency fatigue hydraulic test rig.

Installation & Maintenance Instructions

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

Separate high-power power cables and shielded control wiring in different trunking to avoid harmonic interference from inverters and large motors on analog signals.

Null offset and gain are factory pre-calibrated; only minor electrical trim permitted on-site; disassembly of ServoJet pilot assembly and main spool is strictly prohibited.

Seal all hydraulic ports completely during long-term storage; store in dry dustproof warehouse to slow seal aging and fluid leakage.