MOOG Valve Product Introduction

MOOG is a global leading brand in electro‑hydraulic servo control. Its core products are electro‑hydraulic servo valves and servo‑proportional valves, which achieve high‑precision closed‑loop control of position, velocity, pressure and force for cylinders and hydraulic motors. They are widely applied in test benches, material forming, aerospace, military industry, wind power, metallurgy, motion simulation platforms and other high‑precision working conditions.

Main categories: Nozzle‑flapper two‑stage servo valves (mechanical feedback MFB), integrated‑electronic servo valves with LVDT spool feedback, DDV direct‑drive servo valves, pilot‑operated high‑flow servo proportional valves, servo cartridge valves, explosion‑proof & aerospace special valves.

1. Nozzle‑Flapper Two‑Stage Servo Valves (Mechanical Feedback, Without On‑board Electronics)

Pilot stage: Torque motor plus nozzle‑flapper, mechanical spool feedback, external servo amplifier required. Outstanding stability, industry benchmark. Representative model: G761 / 761 series.

G761‑3000 Series (Classic Flagship)

Flow rate: 0.5‑75 L/min (at ΔP=35 bar), max working pressure 350 bar

Two‑stage nozzle‑flapper structure with spring mechanical feedback. No built‑in electronic board, external servo amplifier is mandatory.

Resolution ＜0.5%, hysteresis ＜3%, high dynamic response, excellent vibration resistance

Applications: Material testing machines, fatigue test benches, motion simulation swing tables, aerospace ground test equipment

Versions: Standard version, intrinsically‑safe explosion‑proof 761K, internal / external pilot oil optional

72 / 78 / 79 Series (High‑Flow Without On‑board Electronics)

72 series: 57‑225 L/min; 79‑100 / 200: 115‑1000 L/min, max pressure up to 480 bar

Two‑stage / three‑stage nozzle‑flapper design, external amplifier required

Used for metallurgical presses, large‑scale fatigue test equipment

24 Series Miniature Servo Valves (Aerospace & Motorsport)

Weight only 95g, compact size, shock resistance up to 50g, temperature range ‑40 ~ +135℃

Max flow 7.5 L/min, applied in F1 racing cars, aerospace actuators, small precision mechanisms

2. Pilot‑Operated Servo Valves with Built‑in Electronics & LVDT Spool Feedback (Mainstream Industrial Type, Direct Connection to PLC Analog Signal)

Equipped with integrated drive board and LVDT spool displacement feedback. External amplifier is not required. Analog or fieldbus signal available, most widely‑selected series.

D661 Series (Industrial Best‑seller, ServoJet Pilot)

ISO05 (NG10) mounting pattern, flow 20‑200 L/min, max pressure 350 bar

ServoJet jet‑pipe pilot stage, better contamination resistance than nozzle‑flapper valves, with built‑in electronics and LVDT spool feedback

Flow control only; fail‑safe spool position upon power loss optional

Application: Injection molding, metal forming, test benches, wind turbine pitch control, fatigue testing

D671 / D672 Series (Multi‑function P/Q Axis Control Valves)

NG10‑NG16 size; support flow control, pressure control, pressure‑flow (P‑Q) compound control, single‑axis closed‑loop control

Analog signal and fieldbus supported; ATEX explosion‑proof version optional

Ideal for complex test systems requiring simultaneous force and displacement control

D791 / D792 Three‑stage High‑Flow Servo Valves

D791: 100‑250 L/min; D792: 400‑1000 L/min

Three‑stage structure (pilot stage + secondary stage + main stage). Deliver large flow while maintaining high dynamic response, with LVDT spool feedback and on‑board electronics

Large‑size hydraulic presses, earthquake simulation tables, heavy‑duty test equipment

3. DDV Direct‑Drive Servo Valves

Direct‑Drive Valve, linear force motor drives spool directly, no pilot oil supply needed. Good contamination immunity, dynamic performance unaffected by pressure fluctuation, spring returns spool to neutral position when power off.

D638 (NG03) / D639 (NG05) DDV Direct‑Drive Valves

Spool directly driven by linear force motor, no pilot stage, no pilot oil source required

Support flow control, pressure control, P‑Q compound control; optional built‑in pressure sensor

Analog signal, Profinet / EtherCAT bus optional

Advantages: Less strict hydraulic oil cleanliness requirement compared with ServoJet / nozzle‑flapper valves. For small‑and‑medium flow systems without stable pilot pressure.

4. D92X / D93X High‑performance Direct‑Acting Servo‑proportional Valves (Solenoid‑driven Spool)

D926 / D927: 3‑position 4‑way, double solenoid; D936 / D937: 4‑position 4‑way single solenoid with fail‑safe position on power loss

NG03 / NG05 size, max flow 180 L/min, integrated electronics and closed‑loop spool feedback

More cost‑effective than DDV valves, for industrial equipment with medium closed‑loop requirements and limited budget.

5. High‑Flow Servo Cartridge Valves

DSHR (2‑way), SE3 (3‑way) Series

Cartridge construction, NG40 ~ NG160 size, max flow up to 20550 L/min

ServoJet pilot plus LVDT main‑spool feedback, high dynamic response for large flow

Used in large hydraulic systems, heavy‑duty presses, integrated manifold blocks for simulation platforms

Selection Reference Table

表格

Key Inquiry Points for Customer Selection

Control objective: Position closed‑loop / Velocity closed‑loop / Force / Pressure closed‑loop / P‑Q compound control

Rated flow, supply pressure; internal or external pilot oil required

Signal type: ±10V analog / 4‑20mA? Fieldbus required (Profinet, EtherCAT)

ATEX explosion‑proof requirement; fail‑safe spool position upon power loss

Hydraulic oil cleanliness; availability of stable independent pilot pressure source (Not required for DDV valves)

Mounting standard: ISO manifold pattern or dedicated Moog mounting pattern

Equipment application: Test bench, hydraulic press, wind power, motion simulation platform, etc.

Notes for picture introduction (for website / Alibaba international): You can add product images for each series: G761 servo valve photo, D661 servo‑jet valve photo, D638 DDV direct‑drive valve photo, D792 three‑stage large flow valve photo, servo cartridge valve photo, manifold installation drawing.