Linuo ZSQ Pneumatic Piston Actuator

High Torque Pneumatic Piston Actuator for Demanding Valve Automation Applications

The Linuo ZSQ Series Pneumatic Piston Actuator is a heavy-duty quarter-turn actuator designed for high torque valve automation applications. Built for reliable operation in industrial process environments, the ZSQ actuator provides superior torque output across the valve stroke, making it ideal for large butterfly valves, ball valves and other quarter-turn valves requiring high breakaway and seating torque.

Unlike conventional rack and pinion actuators, the ZSQ uses a piston and lever-arm mechanism that produces variable torque throughout the stroke. Maximum torque is generated near the closed position where most valves require the greatest force, ensuring dependable operation even in demanding service conditions.

Available in double acting and spring return versions, the ZSQ range supports both on/off isolation duties and automated process control systems.

Key Features

High Torque Output

The piston-driven design generates substantial torque across the operating range, making the actuator suitable for larger valves and higher differential pressure applications. Torque outputs are available from approximately 32 Nm up to 15,000 Nm depending on model and operating pressure.

Double Acting and Spring Return Options

The range includes:

• ZSQ – Double Acting
• ZDQ – Spring Return Fail Close (Heavy Spring)
• ZDLQ – Spring Return Fail Close (Light Spring)
• ZDBQ – Spring Return Fail Open (Heavy Spring)
• ZDBLQ – Spring Return Fail Open (Light Spring)

These options allow actuator selection based on process safety and fail-safe requirements.

Optimized Torque Curve

The actuator delivers higher torque at critical valve positions, particularly during valve breakaway and seating. This makes it especially suitable for control valve applications where torque demand varies throughout the valve stroke.

Adjustable Travel Stops

Bi-directional travel adjustment of ±5° allows accurate valve alignment and commissioning.

ISO 5211 and NAMUR Compatibility

The actuator is supplied with standard mounting interfaces for easy installation of:

• Ball valves
• Segmented Control Valves
• Rotary Plug Valves
• Butterfly valves
• Limit switch boxes
• Solenoid valves
• Positioners
• Position transmitters

The design conforms to ISO 5211 and NAMUR standards for straightforward integration into automated valve systems.

Indoor and Outdoor Service

With robust construction and IP67 suitability, the actuator can be installed in demanding industrial environments including:

• Water treatment plants
• Mining operations
• Chemical processing facilities
• Power generation plants
• Manufacturing facilities
• Food and beverage plants

Technical Specifications

Applications

The Linuo ZSQ pneumatic piston actuator is commonly used for:

• Large butterfly valves
• High torque ball valves
• Process isolation valves
• Water treatment automation
• Mining process systems
• Chemical processing plants
• Petrochemical installations
• Industrial utilities
• Power generation facilities

Why Choose a Pneumatic Piston Actuator?

Pneumatic piston actuators are preferred where torque requirements exceed the practical limits of rack and pinion actuators. Their mechanical advantage provides higher output torque while maintaining reliable and repeatable valve operation.

For larger valves, higher differential pressures or severe service applications, the Linuo ZSQ Series offers a robust and cost-effective valve automation solution.

What is a pneumatic piston actuator?

A pneumatic piston actuator uses compressed air acting on a piston mechanism to generate rotational movement for opening and closing quarter-turn valves.

What is the difference between a piston actuator and a rack and pinion actuator?

Piston actuators typically provide much higher torque outputs and are better suited to larger valves, while rack and pinion actuators are commonly used on smaller and medium-sized valves.

What valves can the ZSQ actuator operate?

The actuator is designed for quarter-turn valves including butterfly valves, ball valves and plug valves.

Is the ZSQ actuator available with fail-safe operation?

Yes. Spring return models are available in both fail-open and fail-close configurations.

What air pressure is required?

The recommended operating pressure range is 5 to 7 bar.

Can positioners and limit switches be fitted?

Yes. The actuator includes NAMUR accessory mounting for easy installation of limit switch boxes, solenoid valves and positioners.