The use of Shewhart control charts when conducting cavitation studies to identify and eliminate non-random causes of variability

Abstract

One of the processes that accompanies the operation of various hydraulic systems is cavitation. This phenomenon is often accompanied by cavitation erosion, that is, the progressive loss of parent material from a solid surface due to continued exposure. The problem of obtaining accurate and reliable data when conducting cavitation studies remains relevant. This article discusses the adaptation of the use of Shewhart control charts when conducting cavitation studies, in order to determine the presence of non-random “special” causes of variability. A graph of changes in the process parameters over time was constructed to carry out statistical control of the stability of the process in order to determine the boundaries of the system variability of the process in order to predict the behavior of the process. As a result of the conducted research, recommendations were developed to increase the accuracy of output data when conducting cavitation studies. It has been confirmed that the use of control charts as a tool for quality control of laboratory measurements allows us to establish that the process has achieved a statistically controlled state, which allows us to maintain a high degree of stability and quality of the research being carried out.This method makes it possible: • to determine the presence of non-random “special” causes of variability during cavitation studies. • to quickly identify and eliminate the “special” causes of variability during cavitation studies.

Keywords

• Cavitation erosion
• Cavitation
• Shewhart control charts
• Causes of process variability
• Statistical methods
• Ultrasonic transformations