Rotary vane actuators are often used for automated pipeline valves and other critical ball and plug valve applications. The hydraulic-powered actuators apply hydraulic force on the rotor’s vanes away from the stationary shoes to produce rotation and perfectly balanced torque output. With no conversion of linear to rotary motion, this actuator technology is highly efficient and ideal for use in high vibration applications such as slurry pipelines, pump and compressor stations.
This quick 2:44 YouTube video, Shafer Rotary Vane Schematic Overview, provides an overview of how these actuators work.
After an introduction of the control components the video shows an animated rotary vane closing and an opening sequence. In the closing sequence, a closed signal pilot pressure enters the control block and forces the pilot piston against the exhaust poppet onto its seat. The power gas poppet is forced off of its seat to pressurize the closing gas hydraulic tank forcing the pressurized fluid into the actuator causing the actuator to close the valve.
The displaced fluid from the actuator flows into the opening gas hydraulic tank which is open to atmosphere through the exhaust check valve in the poppet block. Once the close signal pilot pressure is removed reversing the movement of the poppets and allowing the gas hydraulic tank and operator to neutralize.
Watch the video to the operation of these components during an opening sequence to better understand the operation of these rotary vane actuators.
Visit the Shafer Actuator section on Emerson.com for more on the technology specifically designed for pipeline and other critical applications.