ELECTRIC ACTUATORS
Functional contributions of electric actuators in industrial processes
This article discusses the key advantages of electric actuators , focusing on the types , specifics and how they operate .
Text & images by SMS TORK
Electric actuators are power transmission devices that convert the driving force provided by an electric motor into rotational or linear motion . In rotary electric actuators , the driving force generated by the motor enables the gears within the body to produce rotational movement . This rotation is optimised for specific requirements , such as low speed and high torque for quarter-turn actuators or higher speeds and lower torque for multiturn actuators .
Quarter-turn and multiturn actuators
Quarter-turn electric actuators are commonly used in smaller valves , such as butterfly or ball valves , that require 90-degree rotation for fully open or fully closed positions . In contrast , multiturn actuators are utilised in larger butterfly and ball valves with reducers or directly in globe and knife valves .
Key advantages of electric actuators
The widespread use of electric actuators in industrial applications can be attributed to the following advantages :
• Availability of electricity in most locations
• High torque generation with minimal energy consumption
• Durability and long product lifespan
• Compact and lightweight design
• High protection class
• Precise proportional control capability
• Wide operating voltage range
• Extensive maximum rotation angle tolerance
Electric actuators can be manufactured as on / off controlled electric actuators or proportional controlled electric actuators , depending on the specifications of the connected valve and customer requirements .
• On / off controlled actuators : Provide position feedback at fully open and fully closed positions .
• Proportional controlled actuators : Allow control throughout the entire range of motion and provide real-time position feedback via digital commands or analogue signals ( e . g . current or voltage ).
Manual operation and user-friendliness
Electric actuators are equipped with a manual operation handle in case of a power outage . The handle ’ s position , locking system and torque requirements are optimised for user convenience . Excessive torque or an overly large number of turns for opening / closing operations is undesirable . At TORK , these features are designed and produced to be highly ergonomic and user-friendly , based on extensive research , customer feedback and technical calculations .
Precision and reliability
The mechanical gear system in electric actuators ensures consistent speed and torque throughout the motion , enabling precise proportional control . TORK ’ s quarter-turn actuators provide a precision level of 1 % within a 90-degree rotation , while multiturn actuators achieve up to 0.1 % precision .
Recognition and awards
Independent organisations have recognised TORK ’ s actuators . For example , its multiturn electric actuator received respected design awards , including the Good Design Award ( USA ) and the IF Design Award ( Germany ), in the industrial design category . As a testament to TORK ’ s innovative company culture , it has twice won first place in the “ Innovation Cycle ” category at the Innovation League Awards organised by the Turkish Exporters Assembly ( TI · M ). This achievement highlights the strong integration of innovation into every aspect of its operations . www . valve-world . net Valve World February 2025
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