Modified control chart for monitoring the variance

ABSTRACT. Goal: The main objective of this research paper is to propose a chart, named  Modified Control Chart, where the process variance () allowed be larger than in-control value until maximum (), as long remains capable, in sense that it produces specified (tolerated) small fraction non-conforming items. Design / Methodology Approach: methodology was quantitative approach with statistical analysis simulated data, assess practical impact increase control terms quality requirements. Results: data showed by using proposed Chart number unnecessary interventions could decreased, contributing improve its efficiency. Limitations investigation: assumed mean and known, which unlikely occur real applications. Research considering unknown parameters also progress. Practical implications: S2 Modified detects only genuinely increases variance, significantly rate items being produced, preventing stop assessment for assignable causes if occurs, higher efficiency reduce costs. Originality Value: This introduces new chart monitor characteristics produced capable processes, overcontrol.