Quarter-Turn Electric Actuator

Quarter-turn electric actuators are compact, fast-acting actuators designed for valves whose operating element rotates through 90°, including ball valves, butterfly valves and dampers. A single cycle takes only a few seconds, their dimensions are among the smallest of all actuator types, and their construction is simple and reliable. The website presents quarter-turn electric actuators ranging from small models with torque ratings of several dozen newton-metres for process pipelines to reinforced actuators rated at several thousand N·m for large-diameter trunk pipeline valves. We select equipment for a specific valve or damper and supply it throughout Ukraine with a complete documentation package.

What Is a Quarter-Turn Electric Actuator?

A quarter-turn electric actuator, also known as a part-turn actuator, is an electromechanical device that automatically rotates the valve output shaft through 90° to fully open or close the valve. It is one of the main types of rotary mechanisms used in pipeline valve automation.

Structurally, it is a compact unit combining:

• an electric motor, usually an asynchronous motor designed for 230/380 V or 24 V DC;
• a gearbox with a relatively low gear ratio, since only one 90° rotation is required rather than hundreds of revolutions as in multi-turn actuators;
• mechanical stops at the end positions for accurate fixation in the “open” and “closed” states;
• a control unit with limit and torque switches;
• a microprocessor-based controller with digital Modbus, Profibus and HART interfaces for integration into the process control system in modern models;
• a manual handwheel or lever for emergency operation without electrical power.

The operating principle is simple: when the “Open” command is received, the motor rotates the shaft until it reaches the 90° position, after which the limit switch stops the actuator. The closing process works in the same way. Due to the short travel, quarter-turn actuators provide rapid valve opening and closing, typically within 4 to 30 seconds depending on the model and torque rating.

Main Advantages

This type of actuator is selected according to three main criteria: speed, compact dimensions and reliability of the rotary mechanism.

• • Fast opening and closing. A full cycle takes between 4 and 30 seconds, compared with several minutes for multi-turn actuators.

• • Compact size and low weight. Quarter-turn models are significantly smaller than multi-turn equivalents with a comparable torque rating.
  • Simple and reliable construction. The limited number of moving components provides a long service interval. European industrial models are designed for 50,000–100,000 operating cycles.
  • Accurate positioning. Mechanical stops ensure an exact 90° rotation. Models with an integrated positioner and a 4–20 mA analogue output are available for modulating applications.
  • Low energy consumption. The electric motor operates for only a few seconds during each cycle and consumes minimal power in standby mode.
  • Wide torque range. Available torque ratings range from 20 N·m to more than 8,000 N·m.
  • Explosion-proof execution. Ex d, Ex de and Ex e versions with ATEX/IECEx certification are available.
  • Simple installation. The standard ISO 5211 mounting flange in sizes F03–F25 ensures compatibility with most modern rotary valves.

Where Are Quarter-Turn Electric Actuators Used?

• • Ball valves. Used on gas pipelines, oil pipelines, process pipelines, water supply systems and district heating networks.

• • Butterfly valves. Used at wastewater treatment facilities, water utilities, ventilation systems and process lines.
  • Dampers and throttle valves. Used in ventilation systems, gas and air ducts and process gas pipelines.
  • Plug and conical valves. Used in specialised industrial processes, including applications involving viscous or abrasive media.

The main application industries include oil and gas, petrochemical processing, water supply and wastewater treatment, power generation, food and pharmaceutical production, gas distribution networks and treatment facilities.

How to Select a Quarter-Turn Actuator

A quarter-turn actuator is selected according to six main parameters:

1. Valve torque.
2. Full-stroke operating time.
3. ISO 5211 mounting interface.
4. Power supply.
5. Control type.
6. Operating conditions.

If the valve parameters are unknown or the application is non-standard, send us a completed enquiry form or a photograph of the valve nameplate. Our engineer will prepare a technically justified actuator selection within the shortest possible time.

Buy Quarter-Turn Electric Actuators in Ukraine

The website presents quarter-turn electric actuators for ball valves, butterfly valves, dampers and rotary control valves from the Austrian brand Schiebel.

When you place an order, you receive:

• technical selection of the actuator for a specific valve;
• official supply with a complete documentation package;
• engineering consultation at every stage, from initial selection to commissioning;
• the manufacturer’s warranty;
• fast delivery throughout Ukraine.

The price depends on the torque rating, execution type, whether standard industrial or explosion-proof, and the selected control system. The exact price is calculated after receiving the initial technical data.

Why Customers Choose Us

• Technical selection for a specific application.
• Leading European Schiebel brand.
• Support at every stage of the project.
• Supply throughout Ukraine.
• Complete technical documentation package.

Frequently Asked Questions

What is the difference between a quarter-turn and a multi-turn actuator?

A quarter-turn actuator rotates the valve shaft through 90°, while a multi-turn actuator rotates the stem through tens or hundreds of revolutions. These are two different actuator classes designed for different types of valves.

How should the required torque be selected?

Use the valve manufacturer’s specified torque and add an engineering margin of 25–30%.

Do you deliver throughout Ukraine?

Yes. Delivery is available throughout Ukraine using freight carriers or dedicated road transport.

Are explosion-proof versions available?

Yes. Ex d, Ex de and Ex e models with ATEX/IECEx certification are available.

What full-stroke operating time can be configured?

Depending on the model, the operating time may range from 5 to 60 seconds. Special versions may be configured for either very fast operation or slow modulating movement.

Can the actuator be controlled via Modbus?

Yes. Supported communication protocols include Modbus RTU, Modbus TCP, Profibus DP and HART, with transmission of complete diagnostic and operating data.

Need Help Selecting a Quarter-Turn Electric Actuator?

Submit a request through the website or contact us directly. Our engineer will request the valve parameters and prepare a technically justified commercial proposal.