Comparative Study of Valve-stiction-detection Methods

Abstract

This chapter contains an exhaustive comparative study of methods for detecting stiction in control valves. The study involves 93 different data sets from different process industries, including chemicals, pulp and paper mills, commercial building, and metal processing. The different techniques considered in the study are assessed in terms of efficiency in detecting stiction, possible problems that may occur when applying them to real industrial data, and necessary preprocessing steps and countermeasures to avoid false detections. Achieved results (decision flags and/or index values) are presented and discussed for each method. Statistics for the applicability and indications of the methods are reported. Suggestions are given concerning possible combinations of the methods that lead to reliable stiction-detection results.