Free Process Capability Calculator

Knowing if a process will consistently meet specification is critical, here’s a tool that will help.

You have to manage a system. The system doesn’t manage itself.
W. Edwards Deming

A process is a unique combination of tools, materials, methods, and people engaged in producing a measurable output; for example a manufacturing line for machine parts. All processes have inherent statistical variability which can be evaluated by statistical methods…

The Process Capability is a measurable property of a process to the specification, expressed as a process capability index (e.g., C_pk or C_pm) or as a process performance index (e.g., P_pk or P_pm). The output of this measurement is usually illustrated by a histogram and calculations that predict how many parts will be produced out of specification.

Process capability is also defined as the capability of a process to meet its purpose as managed by an organization’s management and process definition structures ISO 15504.

Two parts of process capability are:

1) Measure the variability of a process, and

2) Compare that variability with a proposed specification or product tolerance.

You can use Minitab to complete process capability studies. For example, Keith Bower has produced some excellent overviews here and here. You can also check out his video below.

If you don’t have access to Minitab, then download my free Excel based calculator by clicking the download link below:

http://www.box.net/shared/hgbcv1c81n

You may also want to download a brief overview of process capability by clicking on the download link below:

http://www.box.net/shared/73ayxyfdsi

Read more here:

4-B Process Capability

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