Statistical quality control charts

الملخص EN

The main purpose of control charts is to help determine if a process is stable and in-control, or unstable and out-of-control.

when a process is stable, or “in control,” this means that it is predictable and affected only by normal random causes of variation.

an unstable or “out-of-control” process is affected by the same common causes of variation, but it is also affected by “special” or “assignable” causes.

this paper reviews the basic concepts on statistical quality control (SQC) and its historical background.

SQC techniques, when applied to measurement data, it can be used to highlight areas that would benefit from further investigation.

these techniques enable the user to identify variation within their process.

understanding this variation is the first step towards quality improvement.

there are many different statistical process control techniques that can be applied to data.

the simplest statistical process control technique to implement is control charts.

the purpose of this technique is to identify when the process is displaying unusual behaviour.

in practice, it has been shown how to apply control charts of variables and attributes to the data from two xamples.