A simple test to confirm control valve stiction

• Main Authors: Shah, Sirish L., Choudhury, M. A. A. Shoukat, Kariwala, Vinay, Douke, Hisato, Takada, Haruo
• Other Authors: School of Chemical and Biomedical Engineering
• Format: Conference or Workshop Item
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Chemical engineering; DRNTU::Engineering::Electrical and electronic engineering::Control and instrumentation::Control engineering
• Online Access: https://hdl.handle.net/10356/91281; http://hdl.handle.net/10220/6032
• Institution: Nanyang Technological University

Stiction is a common problem in the widely used spring-diaphragm type control valves in the process industry. Several methods are available for detecting stiction in control valves. After detection of stiction, a test is required to confirm that the valve in question is indeed suffering from stiction. This paper presents a simple closed loop test, based on changing only the controller gain, for confirming the presence of stiction. The method does not require that the loop be put in manual, which can otherwise upset the plant. The usefulness of this test is demonstrated through simulation studies and an industrial application.