Showing posts with label valve actuation. Show all posts
Showing posts with label valve actuation. Show all posts

New Smart Valve Sensor Provides Preventive Maintenance Diagnostics on Quarter-Turn Valves

MVQ 101
The ifm MVQ101 Smart
Valve Monitor
Good news for valve automation companiesifm’s new smart valve sensor, the MVQ101, provides continuous position feedback and preventive maintenance diagnostics on quarter-turn valves. The sensor features built-in functions that can identify different wear conditions via IO-Link, ifm’s digital communication interface. For example, the sensor can indicate a change in the valve’s operation, which can be a warning that deposits are interfering with the valve’s ability to close or that the seal is wearing.

https://teco-inc.com
800-528-8997



Rack and Pinion Pneumatic Valve Actuators

Rack and pinion actuator
Rack and pinion actuator
(courtesy of Jamesbury)
There are three primary categories of valve actuators commonly used valve automation:
  • Pneumatic
  • Hydraulic
  • Electric
Pneumatic actuators can be further categorized as:
  • Scotch yoke design
  • Vane design
  • Rack and pinion actuators (the subject of this post).
Animation of how rack
and pinion gears convert linear
motion to rotational motion.
Rack and pinion actuators provide a rotational movement designed to open and close quarter-turn valves such as ball, butterfly, or plug valves and also for operating industrial or commercial dampers.

The rotational movement of a rack and pinion actuator is accomplished via linear motion and two gears. A circular gear, referred to a “pinion” engages the teeth of a linear gear “bar” referred to as the “rack”.

Pneumatic actuators use pistons that are attached to the rack. As air or spring power is applied the to pistons, the rack is “pushed” inward or “pulled” outward. This linear movement is transferred to the rotary pinion gear (in both directions) providing bi-directional rotation.


Rack and pinion gear configuration
Actuator rack & pinion gear configuration
Rack and pinion actuators pistons can be pressurized with air, gas, or oil to provide the linear the movement that spins the pinion gear. To rotate the pinion gear in the opposite direction, the air, gas, or oil must be redirected to the other sides of the piston, or use coil springs as the energy source for rotation. Rack and pinion actuators using springs are referred to as "spring-return actuators". Actuators that rely on opposite side pressurization of the rack are referred to as "direct acting".
Most actuators are designed for 100-degree travel with clockwise and counterclockwise travel adjustment for open and closed positions. World standard ISO mounting pad are commonly available to provide ease and flexibility in direct valve installation.

NAMUR mounting dimensions on actuator pneumatic port connections and on actuator accessory holes and drive shaft are also common design features to make adding pilot valves and accessories more convenient.

Pneumatic pneumatic rack and pinion actuators are compact and save space. They are reliable, durable and provide a good life cycle. There are many brands of rack and pinion actuators on the market, all with subtle differences in piston seals, shaft seals, spring design and body designs.

For more information on any pneumatic or electric valve automation project, visit this link or call TECO at 800-528-8997.