DLHZO-LEQ-060-V71/Q/LQ52SB ATOS Servo Proportional Valve 350 bar 70 L/min

Series Overview

The DLHZO series is a range of high-performance direct-operated servo proportional directional valves manufactured by ATOS (Italy). These valves feature a sleeve execution design and are equipped with an LVDT (Linear Variable Differential Transformer) position transducer for closed-loop spool position control. They provide precise directional control and uncompensated flow control proportional to the input electrical signal.

The core technical features of the DLHZO series include zero-overlap spool design—the spool slides within a precision-machined and hardened sleeve, achieving exceptional metering accuracy. The sleeve is pressed into the five-chamber valve body, and the spool is directly actuated by proportional solenoids with LVDT closed-loop position control. The coils are fully plastic-encapsulated (Class H insulation), providing vibration resistance, shock resistance, and environmental robustness.

The DLHZO series offers multiple variants:

• DLHZO-T: With LVDT position transducer

• DLHZO-TEB: With on-board analog amplifier (basic)

• DLHZO-TES: With on-board digital amplifier (full-featured)

• DLHZO-TEZ: With on-board digital amplifier + axis controller

• RTE: Rugged execution (with position transducer and integral analog electronics)

All DLHZO series servo proportional valves supplied are genuine ATOS original products, ensuring 100% interchangeability with original equipment. Every unit undergoes rigorous application-specific simulation testing prior to shipment to guarantee optimal performance in your actual operating conditions.

Model 1: DLHZO-LEQ-060-V71/Q/LQ52SB

Product Overview

The DLHZO-LEQ-060-V71/Q/LQ52SB is a specific configuration of the ATOS DLHZO series high-performance direct-operated servo proportional directional valve. Featuring sleeve execution and an LVDT position transducer for closed-loop position control, this valve provides directional control and uncompensated flow control proportional to the input electrical signal.

Model Code Decoding:

• DLHZO = Direct-operated servo proportional valve, sleeve execution, size 06 (ISO 4401)

• LEQ = Spool type and characteristics code

• 060 = Size 06 (ISO 4401 standard)

• V71 = Spool type (V-series spool)

• /Q = Electronic option (enable signal)

• LQ52SB = Specific configuration option code

Technical Specifications (Bulleted List)

• Model: DLHZO-LEQ-060-V71/Q/LQ52SB

• Valve Type: Direct Operated Servo Proportional Directional Valve

• Valve Execution: Sleeve Execution

• Spool Overlap: Zero Overlap

• Position Transducer: LVDT (Linear Variable Differential Transformer)

• Nominal Size: Size 06 (ISO 4401 standard)

• Mounting Interface: ISO 4401 standard size 06

• Max. Operating Pressure: 350 bar

• Max. Flow Rate: 70 L/min

• Max. Solenoid Current: 2.6 A

• Coil Resistance (at 20°C): 3 – 3.3 Ω

• Supply Voltage: 24V DC (rectified and filtered, VRMS = 20 – 32 V)

• Response Time: < 5 ms (DLHZO-TE series)

• Hysteresis: < 0.5%

• Sealing Material: NBR / FKM (optional)

• Hydraulic Fluid: Mineral oil (ISO VG 46, based on oil temperature 50°C)

• Fluid Temperature: -20°C to +70°C (standard)

• Material: Cast iron body

• Weight: Approx. 2.3 kg

• Bolt Height: 38 mm

Key Technical Advantages

1. LVDT Closed-Loop Position Control: The DLHZO-LEQ-060-V71/Q/LQ52SB features an LVDT position transducer enabling high-precision closed-loop spool position control. The LVDT provides non-contact measurement with infinite resolution, high repeatability, and extended service life. Closed-loop control ensures precise correlation between spool position and input signal, maintaining stable flow control characteristics even under varying hydraulic forces and load disturbances.

2. Sleeve Execution with Zero Overlap: The spool slides within a precision-machined and hardened sleeve, achieving exceptional metering accuracy. Zero overlap design provides extremely high sensitivity near the null position. The sleeve is pressed into the five-chamber valve body—this construction ensures precise fit between spool and sleeve, minimizing internal leakage and maximizing volumetric efficiency and control accuracy.

3. High Dynamic Response Performance: The DLHZO series offers high dynamic response characteristics. The DLHZO-TE series achieves response times below 5 ms with hysteresis less than 0.5%. This superior dynamic performance makes these valves ideal for high-frequency, high-precision closed-loop control applications including position control, velocity control, and pressure control.

4. Fully Plastic-Encapsulated Coils, High Environmental Robustness: The solenoid coils are fully plastic-encapsulated (Class H insulation) , providing vibration resistance, shock resistance, and environmental robustness. This enables the DLHZO series to maintain stable operation in harsh industrial environments with severe vibration, wide temperature fluctuations, and high humidity.

5. Diverse Spool Type Options: The DLHZO series offers multiple spool types (L0, L1, V1, L3, V3, L5, T5, L7, T7, D7, DT7, etc.), covering linear flow characteristics, non-linear flow characteristics, and differential control for different application requirements. Users can select the appropriate spool configuration based on specific control needs.

Application Areas

• Injection molding machine hydraulic system position, velocity, and pressure closed-loop control

• Press and forging equipment precision motion control

• Machine tool hydraulic servo systems (grinding machines, broaching machines)

• Test benches and dynamic simulation equipment high-frequency response control

• Wind turbine pitch control systems

• Marine and offshore hydraulic servo systems

• Metallurgical equipment (rolling mills) hydraulic automatic gauge control (AGC)

Expert Maintenance Tips

• Verify the valve mounting interface meets ISO 4401 standard size 06 requirements before installation. The mounting surface should be flat with surface roughness Ra ≤ 0.8 μm to ensure proper sealing.

• System fluid cleanliness should meet ISO 4406 standard 19/17/14 or better, with filtration accuracy not less than 10 μm recommended. The tight clearance between spool and sleeve makes the DLHZO series particularly sensitive to fluid contamination.

• The LVDT position transducer is a precision component. Avoid impact or mechanical damage to the transducer area during installation and removal.

• Supply voltage should be stable within 20 – 32 V DC range (rectified and filtered). Voltage fluctuations affect solenoid thrust and valve response characteristics.

• Before initial system power-up, configure and calibrate the amplifier parameters. For TEB/TES integrated amplifiers, factory presets ensure excellent performance and valve-to-valve interchangeability.

• Regularly inspect electrical connector reliability. The standard 7-pin connector is used for power supply, analog signal input, and monitoring signals.

Model 2: QVHZO Series — Digital Proportional Flow Valve

Product Overview

The QVHZO is a digital proportional flow valve from ATOS, direct-operated, pressure compensated, and equipped with an LVDT position transducer. The valve offers 2-way or 3-way connections, delivering precise flow control based on application requirements. The QVHZO series is available in TEB basic execution (with analog reference signal or IO-Link interface) and TES full execution (with optional fieldbus interfaces).

The key difference between QVHZO and DLHZO: QVHZO is a proportional flow valve (focusing on flow control with pressure compensation), while DLHZO is a servo proportional directional valve (focusing on directional control and flow control without pressure compensation).

Technical Specifications (Bulleted List)

• Series: QVHZO

• Valve Type: Direct Operated Digital Proportional Flow Valve

• Pressure Compensation: Pressure compensated

• Position Transducer: LVDT

• Nominal Size: Size 06 (ISO 4401 standard)

• Max. Operating Pressure: 210 bar

• Max. Flow Rate: 45 L/min

• Response Time: Approx. 25 ms

• Amplifier Type: TEB (basic) / TES (full)

• Communication Interfaces: CANopen (BC), PROFIBUS DP (BP), EtherNet/IP (EI), PROFINET (EP), POWERLINK (EW)

• IO-Link Interface: Optional (TEB only)

• Bluetooth Option: Optional (/T option)

• Mounting Interface: ISO 4401 standard size 06

• Hydraulic Fluid: Mineral oil

• Weight: Approx. 2.3 kg

Key Technical Advantages

1. Pressure Compensated Flow Control: The QVHZO series integrates pressure compensation to maintain constant set flow regardless of load pressure variations. This makes it ideal for velocity control applications—actuator speed remains unaffected by load changes.

2. High-Precision LVDT Feedback: Equipped with an LVDT position transducer for optimal flow regulation accuracy. The LVDT’s non-contact measurement principle ensures long-term stability and high repeatability.

3. Flexible Digital Communication Capabilities: The TES full execution supports multiple fieldbus interfaces (CANopen, PROFIBUS DP, EtherNet/IP, PROFINET, POWERLINK) for seamless integration into modern industrial automation networks. The TEB basic execution supports IO-Link interface for digital parameter setting and real-time diagnostics.

4. Smart Tuning and Mobile Commissioning: Supports Atos CONNECT mobile App (via Bluetooth) and E-SW-SETUP PC software for parameter setting and diagnostics. The Bluetooth/USB port is always present, enabling quick access to valve main functional parameters without physical cable connection.

5. Flexible Connection Options: QVHZO valves offer 2-way or 3-way connections based on application requirements. In 2-way connection, the P port is blocked; in 3-way connection, the P port is connected to tank or other user lines.

Application Areas

• Hydraulic actuator velocity control (cylinder feed speed, motor speed control)

• Constant flow control hydraulic systems (unaffected by load variations)

• Injection molding machine injection speed control

• Machine tool hydraulic feed systems

• Test equipment precision flow control

• Industry 4.0 hydraulic systems requiring digital communication

Expert Maintenance Tips

• QVHZO valves are pressure-compensated flow valves. Verify P and T port connections comply with design requirements (2-way or 3-way connection) before installation.

• System fluid cleanliness should meet ISO 4406 standard 19/17/14 or better. The tight clearance between spool and sleeve makes the QVHZO series sensitive to fluid contamination, which directly affects flow control accuracy and valve service life.

• For TEB/TES valves with on-board amplifiers, use the Atos CONNECT mobile App (via Bluetooth) or E-SW-SETUP PC software for parameter setting and diagnostics. This significantly reduces commissioning time.

• The Bluetooth option (/T) enables Bluetooth connectivity via the E-A-BTH adapter. A personal password can be set to protect Bluetooth connections from unauthorized access.

• Regularly inspect electrical connection reliability. The 7-pin (or 12-pin) connector on TES full execution valves is used for power supply, analog signal input, and monitoring signals.