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Glossary

Cp

Potential process capability index

Compares the tolerance width with the process spread. It does not look at whether the process is centred.

Formula

Cp = (USL − LSL) ÷ 6σ

Cp answers whether the process fits within the tolerance at all, if it were set perfectly. Cp equal to 1 means the spread exactly fills the tolerance band.

Example

A tolerance of 6 ±0.3 g and a standard deviation of 0.05 g give Cp = 0.6 ÷ 0.3 = 2.0.

What it looks like in the system

Calculated together with Cpk for every characteristic, machine and mould cavity. The capability report exports to CSV, XLSX and PDF.

Capability report: Cp and Cpk of every characteristic with export to CSV, XLSX and PDF
DiGi Smart Control

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