13. MSA – Type I Gage R&R

Type I study helps observer to evaluate respective gauge’s repeatability (Cg) and bias (Cgk), these 2 types of indicators can help to analyze gauge consistency and correctness of the gauge.

Calculated equation is given below:


Example for type I calculation is given below:

One of the inspection gauge’s length results has a measuring average of 1.71351 mm with a standard deviation of 0.002115 mm, while the reference value for the gauge indicated 1.708 mm. The specification tolerance is ±0.07 mm.

The calculated results indicated that Cg and Cgk exceeds both 1.33 (min value), these 2 indicator shows that the gauge is capable to measure repetitively and has high accuracy for reading value. The following control chart is the summarized example for the Cg/Cgk plotting.

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