Any quality professional worth his keep knows that gauge repeatability and reproducibility (R&R) studies are a critical part of a successful process control system, but it is amazing how many do not understand how to properly conduct a study or how to interpret the results.
Quality professionals know that measuring manufactured products is critical to maintaining the customer specification. They also know that measuring products is necessary for statistical process control systems designed to improve the manufacturing process itself. What is sometimes forgotten is that the data is only worthwhile if the measurement system itself is adequate.
A gauge R&R study will tell operators if the measurement system is acceptable for its intended use. The gauge study also shows which part of the measurement system is contributing the most to the variation of the measurements and helps operators plan improvements to the system.
Measurement systems contain variation from three main sources: the products themselves, the appraiser taking the measurements and the equipment used to perform the measurement. The gauge study shows the contribution of each of these areas.
In an adequate measurement system, one would expect to find most of the variation within the products. If the bulk of the variation is created by the appraisers or the equipment, then the system may not be suitable.
This series of blogs will include:
- Conducting a Study
- Evaluating the Gauge Study: The TV Report
- Evaluating the Gauge Study: The TT Report
- Evaluating the Gauge Study: The Average and Mean Report