D634-1055
May 25, 2026

D634-1055

The D634-1055 is a single‑stage, direct‑drive servo valve in the MOOG D634 series. It uses a permanent magnet linear force motor to drive the spool directly—no pilot oil required. Built‑in 24 VDC electronics and LVDT closed‑loop spool position feedback deliver high accuracy and dynamic response largely independent of supply pressure. Spring‑centered design ensures the spool returns to neutral on power loss (fail‑safe). Optimized for medium‑flow, high‑dynamics applications.

Description

1. General Description

The D634-1055 is a single‑stage, direct‑drive servo valve in the MOOG D634 series. It uses a permanent magnet linear force motor to drive the spool directly—no pilot oil required. Built‑in 24 VDC electronics and LVDT closed‑loop spool position feedback deliver high accuracy and dynamic response largely independent of supply pressure. Spring‑centered design ensures the spool returns to neutral on power loss (fail‑safe). Optimized for medium‑flow, high‑dynamics applications.

2. Hydraulic Specifications

  • Max working pressure (P, A, B): 350 bar (5,000 psi)Moog Inc.

  • T‑port pressure: 50 bar (without Y‑port); 350 bar (with Y‑port)Moog Inc.

  • Rated flow (Δp = 35 bar per land): 100 L/min (26.4 gpm)

  • Maximum flow: approx. 185 L/min (48.8 gpm)Moog Inc.

  • Internal leakage: ≤ 0.8 L/min

  • Fluid: Mineral oil (ISO 11158 / DIN 51524)

  • Fluid temperature: −20 °C to +80 °C

  • Filtration: ISO 4406 17/14/11 or better

  • Weight: approx. 6.5 kg (14.3 lb)

3. Dynamic Performance (Typical)

  • Step response (0→100% stroke): ≤20 msMoog Inc.

  • −3 dB bandwidth: 60–70 Hz

  • Hysteresis: <0.4% of full scaleMoog Inc.

  • Resolution: <0.1% of full scale

  • Null drift (60 K temp change): <1.2% of full scale

4. Electrical Specifications

  • Supply voltage: 24 VDC (18–32 VDC)Moog Inc.

  • Max operating current: 3.5 A

  • Command signal (jumper selectable): ±10 V, ±10 mA, 4–20 mAMoog Inc.

  • Spool position feedback output: 0–10 VDC

  • Connector: M18, 6 pins + PE, IP65Moog Inc.

  • Ambient temperature: −20 °C to +60 °C

  • EMC: CE compliant

5. Key Features

  • Pilot‑free direct drive: simple installation, high reliability

  • Integrated closed‑loop control: precise, repeatable positioningMoog Inc.

  • Pressure‑independent dynamics: stable performance under varying loads

  • Low internal leakage: energy efficientMoog Inc.

  • Spring‑centered fail‑safe: safe system shutdown on power lossMoog Inc.

6. Applications

  • High‑precision hydraulic presses

  • Dynamic material testing machines

  • Fatigue test systems

  • Closed‑loop position, velocity, and pressure control

  • Industrial automation and motion control

7. Wiring Definition

  • Pin 1: +24 VDC

  • Pin 2: Power ground

  • Pin 3: Command signal (+)

  • Pin 4: Command signal (−)

  • Pin 5: Spool position feedback (0–10 VDC)

  • Pin 6: Feedback ground

  • PE: Protective earth

  • Recommendation: Use shielded twisted‑pair cable for signals.


Get a Quote