Thursday, July 6, 2017

Added Safety For Pneumatic Actuators

pneumatic actuator for industrial process control valve
XL Series Pneumatic Actuator
Courtesy Emerson - Hytork
Manufacturers of industrial process control gear keep the safety of their customers as a high priority item when designing products. There is much at stake in industrial operations, so every instance where the probability or impact of failure can be reduced is beneficial.

Pneumatic valve actuators utilize pressurized air or gas as the motive force to position a valve. A common version of these air powered actuators employs a rack and pinion gear set that converts the linear movement of air or spring driven pistons to rotational movement on the valve shaft. When one side of the piston is pressurized, the pinion bearing turns in one direction. When the air or gas from the pressurized side is vented, a spring (spring-return actuators) may be used to rotate the pinion gear in the opposite direction. A “double acting” actuator does not use springs, instead using the pneumatic supply on the opposing side of the piston to turn the pinion gear in the opposite direction.

From time to time, service or maintenance operations for the actuator may require opening of the pressure containing case. This is a potentially hazardous step and confirmation that the case is not pressurized when disassembly is undertaken is essential to a safe procedure. Many pneumatic actuators have cases assembled with numerous threaded fasteners. Hytork, an Emerson brand, employs a keyway and flexible stainless steel key to affix the end caps to their XL Series pneumatic actuators. This method provides a number of benefits, not the least of which is preventing the removal of the key and end cap if the case is pressurized.

Find out more about the XL Pneumatic Actuators in the illustrated piece provided below. Share your industrial fluid control challenges with industrial valve and automation specialists, combining your own process experience and knowledge with their product application expertise to develop effective solutions.