GRAPHICS-ORIENTED SOFTWARE, FOR THE DESIGN OF QUALITY CONTROL CHARTS

Abstract

The use of control charts in the interpretation of patterns of variation is a well known tool of statistical quality control. Inspite of the apparent simplicity of the control charts, it takes a great deal of time -to -manually calculate the trial control limits and to draw preliminary conclusions from it. In order to make better decision on engineering tolerances, better comparison between alternative design and alternative production methods, a PC-based, graphics-oriented software has been developed both for variables and attribute control charts. The software, comprising of a preprocessor, main program module, and the postprocessor, is highly interactive. The post processor makes possible diagonosis and correction of many production troubles thereby increasing the productivity. The visual representation of statistical data on the colour graphics terminal, indeed gives a clear understanding as to whether the process is in control or not. The necessary steps involved in the construction of charts have been totally programmed. This package will be an aid for the people at the management and at the production level. The package has options to select : X and R chart, X and a-_chart, np-chart, 100p-chart, U-chart, C-chart. The Preprocessor ' asks the numerical data from the user depending upon the type of chart of user selects from the Menu.