Tuesday, November 22, 2016

Review: Vane Actuators

vane actuator
An internal view of a vane actuator allowing you
to see the one piece vane and shaft, lip seals,
travel stops, and the clam shell  design.
The vane actuator is a simple and elegant mechanism for quarter-turn valves, dampers, and other rotary motion applications. The vane actuator produces rotary motion through the application of air pressure to a "vane' attached directly to an output shaft. In higher quality vane actuators, the vane and shaft are machined from a single piece of steel. Because of this, any motion from the vane is transferred directly to the shaft, without backlash or lost motion.

The vane includes “lip seals” that isolate the vane and shaft from the air supply. The lip seal design provides several advantages, namely eliminating the need for shaft seals and an inherent cleaning action internally. A split, or “clam-shell” housing is assembled around the vane, totally enclosing it. When supply air is applied to one side of the vane, torque is produced moving the vane in one direction. Accordingly, there is direct rotary motion transfer to the shaft, with 100% efficiency. Torque is controlled by surface area of the vane and the differential pressure on either side of the vane. Bi-directional over-travel is limited by the use of travel stops mounted in both sides of the housing.

The Kinetrol Vane Actuator
The Kinetrol Vane Actuator
Single acting vane actuators use a spring to return the actuator to its resting position. By adding a spring, vane actuators can fail-open or fail-closed in the event of power failure. Double acting actuators use supply air on either side of the actuator to dictate clockwise or counter-clockwise movement. Other types of pneumatic actuators generally require high quality air as their power source, but vane actuators can accept poorer quality supply air, as the vane design uses the vane’s “wiping action” to push dirt and grime out of the way. Vane actuators are generally more compact that other types of actuators and come in many sizes, producing a wide range of torques.

For more information about vane actuators visit http://www.kinetrolusa.com or call 972-447-9443.