Kinetrol Solves Scotch Yoke Actuator Reliability Issues on Top Entry Ball Valves

A southeastern chemical company had reliability issues with the leading brand of scotch yoke actuators. The actuators were mounted on 12" top entry ball valves that sent process reactor off-gas to a dryer for processing. The actuators cycle the valves every two minutes.

Top entry ball valve automation is challenging because the adjustable ball stops on top entry ball valves can increase torque values, and undersized actuators are common. In this application, the scotch yoke actuators were also unreliable due to seal leaks, sticking, and lock up, which dramatically affected the plants production of PTA (purified terephthalic acid).

The first Kinetrol actuator installation for this application, a 187-100, was installed at the chemical plant 1997, and it is still in service today. By our calculations, that actuator has cycled 5,148,000 since then, considering it strokes every two minutes, 24 hours a day, 7 days a week for 325 days a year.

For more information, contact Kinetrol USA.
https://kinetrolusa.com
972-447-9443

Kinetrol Actuator "Insures" Rapid Valve Closing to Protect Equipment, Infrastructure, and Personnel

20" high performance
butterfly valve with
Kinetrol actuator

An insurance mandate required a major chemical company who produces PTA (Purified Terephthalic Acid) to install a 20" automatic high performance butterfly valve with the capability to stroke from fully opened to fully closed in less than one second.

Requirement:

It's necessary to prevent a $30M USD axial process air compressor from rapidly going into an overspeed condition that could harm equipment, infrastructure, and personnel. 

Challenge:

The biggest challenges: stroking the valve in under one second, but without slamming the butterfly disc into the stops which can damage the valve and nearby equipment. 

Solution:

Kinetrol's expertise in rapid cycling enabled us to size, select, and perform certified cycle time tests on the final assembly. This shut out any competition. 

Assembly: 

20" class 300 high performance butterfly valve, Kinetrol 207-120 with a 2" automatic L-Port, 3-way, compressed air supply ball valve with 097-F120, X-proof solenoid, and two exhaust silencers coupled to the size 20 supply port. Open / closed limit switch assembly. Robust SST mounting bracket and coupling. The closure time once actuator air is exhausted: 0.13 seconds.