Control chart are one of the 7 QC tools. Control charts are actually the graphs on which the quality of the product is plotted as manufacturing or servicing is actually proceeding
Mr. Shewart, an American, has been credited to develop the control charts for variable and attribute data at Bell Telephone Industries.
Control charting enables everyone to make decision and to know the degree of confidence with which the decisions are made. There may be some margin of error. No technique, even 100% automated inspection, can guarantee the validity of the result; there is always some room to doubt.
Control chart graphically, represents the output of the process and us statistical limits and patterns of plot, for decision making
The elements of control chart are :1. Horizontal axis for sample number; 2. Vertical axis for sample statistics e.g. mean, range, standard deviation of sample, 3. Target Line, 4. Upper control line, 5. Upper warning line,6. Lower control line, 7. Lower warning line,8. Plotting of sample statistics, 9. Line connecting the plotted statistics.
No comments:
Post a Comment