MOOG G771K & G772K Series Servo Valves: Complete Obsolete-to-Upgrade Model Cross-Reference Guide

Overview
The MOOG G771K and G772K series are high-performance, two-stage electro-hydraulic servo valves with mechanical feedback (MFB), designed for precise directional, position, velocity, pressure, and force control in demanding industrial hydraulic systems. As part of MOOG's renowned G77XK family of intrinsically safe protected industrial servovalves, these valves carry multiple international certifications including ATEX (Ex ia IIB/IIC T4 Ga), IECEx, FM, CSA, and TIIS, making them suitable for hazardous area installations requiring intrinsic safety or non-incendive protection.

Official Upgrade Replacements
MOOG has officially phased out many legacy G771K and G772K models and replaced them with enhanced versions featuring improved dynamic response, superior contamination tolerance, optimized internal sealing, and extended service life. All replacement models maintain complete mechanical and electrical interface compatibility, allowing direct drop-in substitution without modifying manifold blocks, conduit connections, or control software.

G771K Series – Obsolete to Upgrade Replacement:

Obsolete Model Upgrade Replacement
G771K200A G771K289A
G771K201A G771K287A
G771K202A G771K293A
G771K203A G771K291A
G771K208A G771K294A
G771K226A G771K288A
G771K227A G771K292A
G771K240A G771K289A
G771K241A G771K287A
G771K242A G771K293A
G771K244A G771K294A
G771K247A G771K235A
G771K260A G771K290A
G771K297A G771K355A
G771K298A G771K354A
G771K299A G771K356A
G771K624A G771K305A
G771K625A G771K301A
G771K626A G771K304A
G772K Series – Obsolete to Upgrade Replacement:

Obsolete Model Upgrade Replacement
G772K240A G772K336A
G772K241A G772K337A
G772K272A G772K336A
G772K273A G772K337A
G772K340A G772K357A
G772K619A G772K339A
G772K620A G772K338A
What Makes the Upgrade Replacements Better?
Enhanced Dynamic Response – Faster frequency bandwidth and step response for precision motion control

Superior Null Stability – Advanced materials and tighter spool/sleeve matching reduce temperature-induced drift

Improved Contamination Resistance – Optimized internal clearances and self-cleaning pilot stage design lower maintenance frequency

Extended Service Life – Upgraded metallurgy and sealing withstand millions of cycles with minimal leakage increase

Complete Drop-In Compatibility – Same mounting dimensions, hydraulic port configurations, and electrical input signals

Multi-Certification Approvals – ATEX, IECEx, FM, and CSA certified for hazardous area applications

Technical Specifications
Parameter G771K Series G772K Series
Valve Type Two-stage, mechanical feedback Two-stage, mechanical feedback
Pilot Stage Nozzle-flapper / jet-pipe Nozzle-flapper / jet-pipe
Rated Flow 4 – 60 L/min Up to 240 L/min
Max Pressure 210 – 315 bar Up to 350 bar
Mounting Pattern ISO 10372 (Size 02) ISO 10372 (Size 03)
Hysteresis ≤ 3.0% ≤ 3.0%
Operating Temp -40°C to +135°C -40°C to +135°C
Intrinsic Safety ATEX / IECEx / FM / CSA ATEX / IECEx / FM / CSA
Applications
These servo valves are deployed across power generation (gas and steam turbine fuel control, inlet guide vane control), steel and metals (rolling mill AGC, tension control), injection molding, aerospace test rigs, heavy hydraulic presses, and oil & gas facilities.

Supplier Information
For brand new original MOOG G771K and G772K series servo valves – factory-sealed, in stock, and ready for immediate shipment – contact:

Wuhan Yuli Automation Technology Co., Ltd.

Contact: Manager Qin

Phone: +86 15997483088

Email: 445692254@qq.com

Address: Anputon Town, Donghu New Technology Development Zone, Wuhan, Hubei, China

Normen & Konformität

• ✓ ISO