Vane, Shaft and Seal Design: The Critical Difference in Pneumatic Rotary Valve Actuators

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The vane actuator produces rotary motion through the application of air pressure to a "vane' attached directly to an output shaft.

There are several manufacturers of pneumatic, rotary vane valve actuators on the market. Outwardly they appear similar. Internally, there's a world of difference in their design and their performance.

In higher quality vane actuators, the vane and shaft are machined from a single piece of steel. Casting and machining adds cost, but also adds performance. Lower quality actuators save cost by using a 2-piece vane/shaft combination. These are more likely to be affected by backlash or lost motion.  In other words, a one-piece shaft and vane assembly transfers 100 percent of the vane movement directly to the shaft. Two-piece designs may lose movement over time, reducing control and accuracy.

Higher quality pneumatic vane actuators incorporate a pair of “lip seals” around the vane. The durable and resilient polyurethane seals provide two key benefits; eliminating the need for o-rings; and eliminating shaft seals. Dual, opposing lip seals are located each side of the vane. They isolate the vane and shaft from the air supply and create an area from the shaft through the center of the vane that remains unpressurized, eliminating the need for pressure seals around the top and bottom of the shaft.

Some lower quality vane actuator designs use an o-ring around the entire vane, exposing the o-rings to mechanical stress and rolling. Higher quality actuators back their polyurethane lip seals with stainless steel expanders that maintain the integrity of the seal to the actuator housing.

The heart of the pneumatic vane actuator is simple design. Manufacturers often promote the concept of "a single moving part", referring to the vane/shaft/seal assembly. But despite this claim, all pneumatic vane actuators are not the same. You owe it to yourself and your organization to "look under the hood".  See what level of engineering and quality you're really getting.

How Kinetrol Pneumatic Rotary Vane Actuators Work

Kinetrol pneumatic rotary vane actuators use a one piece vane and shaft produce rotary torque on the shaft output drive. The vane is assembled inside a 2-piece clam-shell enclosure. The presence of the vane creates two air chambers. By pressurizing and venting opposing chambers, the resulting pressure differential across the vane provides torque to the shaft. Torque output of the rotary vane actuator remains constant throughout the full rotation of the shaft.

http://www.kinetrolusa.com | 972-447-9443

Kinetrol Pneumatic Actuators for Portland Cement Production

Cement valve using Kinetrol Actuator

Portland cement is a fine powder, gray or white in color, that consists of a mixture of hydraulic cement materials comprising primarily calcium silicates. More than 30 raw materials are known to be used in the manufacture of portland cement. These materials are chemically combined and subjected to subsequent mechanical processing operations to form gray and white portland cement. Gray portland cement is used for structural applications and is the more common type of cement produced. White portland cement has lower iron and manganese contents than gray portland cement and is used primarily for decorative purposes.

Typically, these raw materials are obtained from open-face quarries, underground mines, or dredging operations.  When mining, pockets of pyrite, which significantly increase emissions of sulfur dioxide (SO2), can be found in deposits of limestone, clays, and shales used as raw materials for portland cement.

Transport of the raw materials is accomplished by a variety of mechanisms, including screw
conveyors, belt conveyors, drag conveyors, bucket elevators, air slide conveyors, and pneumatic conveying systems. A variety of valves, gates, and dampers are required to accurately control the flow of raw materials as they are being discharged from pipes, silos, bins and hoppers. These flow control devices all have one thing in common - the actuators that control their opening and closing are exposed to extremely dusty and dirty atmospheres, with significant amounts of vibration - and they are almost always located in an area where repairs are very costly.

Kinetrol vane actuators are used to automate these gate, butterfly and mixer valves because of their ruggedness and their reliability. Additionally, Kinetrol pneumatic actuators have a smaller footprint and consume less air compared to other pneumatic actuators or conventional linear pneumatic cylinders, resulting in significant savings in energy costs.

Kinetrol USA Wishes the Food and Beverage Industry a "Blue Christmas"

Kinetrol's Neil Meredith standing
next to Kinetrol's "Blue Christmas Tree"
(all the various size Blueline actuators
stacked on top one another.)

Kinetrol USA thinks this Christmas should be "blue" for the foodservice and beverage processing industry. Not blue in the sense of Elvis' sad song, but rather blue in the sense of the new "Blueline" series actuator.

Finally, food and beverage producers have access to the excellent performance of the Kinetrol rotary vane actuators specially coated for use in the harsh wash-down environments common in the food industry.  These actuators comply with the Federal Food, Drug and Cosmetic Act (FDA) and all applicable regulations, including 21 CR 175.300 (Code of Federal Regulations).

The actuators are intended to be installed in areas where harsh chemical wash-down is required. These areas are very tough on most types of pneumatic actuators because the caustic or acidic chemicals used in cleaning adversely effect the actuator.

For more information contact Kinetrol USA at http://www.kinetrolusa.com or call 972-447-9443.

14 Reasons to Choose the Kinetrol AP Pneumatic Valve Positioner

AP postioner on Kinetrol actuator.

The AP pneumatic positioner combines smoothness and accuracy with convenience and simplicity of use. It provides unparalleled performance and real industrial robustness, easy calibration, and is well adapted to a whole range of valve and damper applications. AP options include high flow valves, direct mount or industry standard discrete mount housings, 4-20mA angle retransmit, limit switches, Clear Cone position indicator as well as I/P convertors. Below are 14 features that make the AP positioner a standout among all other valve positioners.

1. Enclosure and Lid – robust die-cast metal with tough corrosion-resistant epoxy coating and O-ring sealing. Layout gives easy access to all adjustments on removal of lid.
2. Spool Valve – highly reliable, all metal, 5 port proportional valve controls the air flow. Three versions, with different flowrates, are easily interchangeable.
3. Carrier Plate Assembly – integrated assemblies carrying the feedback shaft and cam plus angle retransmit drive and pot (when specified). Easily removed for conversion or maintenance.
4. Interchangable Port Plate – easily convertible for different flowrate options.
5. Feedback Pot Drive – zero backlash, proven trouble free for life.
6. Retransmit Pot – high quality conductive plastic servo–type with ball bearings. Proven long life and high precision.
7. Actuator Interface – options include NAMUR standard, Kinetrol male square or Kinetrol direct mount female square. Quick external conversion allows bracket mounting to any rotary or linear actuator.
8. Internal Angle Scale – with adjustable indicator for easy field calibration.
9. Exhaust Snubber Screws – allow travel speed reduction down to 1/ 3 x full speed, independently in each direction, by screwing in to restrict exhaust air flow.
10. Gauge Port – as standard.
11. Span and Zero Adjustment – quick and easy thumbwheel setting with slotted locking screw.
12. Feedback Cam – quick and easy reversal ( for rotational sense handing) or replacement (to change the response characteristic) of the cam is facilitated by a spring loaded retention device.
13. Feedback Shaft – innovative collet connection permits quick – fit/release of the actuator interface and eliminates backlash.
14. Airflow Changeover Block – allows selection of direction in which positioner moves (for direct mount models).

Kinetrol Product Catalog October 2017

Most recent version of Kinetrol catalog including Blueline coating for foodservice applications. Kinetrol rotary vane actuators are used to operate or position ball, butterfly and plug valves, ventilation dampers and automatic doors. Uses also include movement and positioning of components during manufacture - in fact anything that needs to be turned through 90° or less, automatically or by remote control.

You can download the Kinetrol Product Catalog from the Kinetrol USA site here.

Kinetrol Product Catalog October 2017 from Kinetrol USA

Kinetrol Actuators Performing Reliably Around the World

For over 50 years Kinetrol has been providing trouble-free valve and damper actuators to the chemical, biofuel, food & beverage, metal, mineral, oil, gas, pharmaceutical, power generation, paper, textile, water, wastewater, and transportation industries.

Visit Kinetrol USA at http://www.kinetrolusa.com or call 972-447-9443.

Check out the video below for a sampling of the harsh applications where Kinetrol vane actuators thrive.