Abstract
A new measure for evaluating fit quality of mating parts via Fit Capability Indices (FCIs) is introduced as an interface between fit quality and process control of the mating parts. Fit Capability Analysis method is discussed based on the relationship between FCIs and Process Capability Indices (PCIs). A new statistical tolerancing approach for assuring predetermined fit quality is developed on the basis of fit quality evaluation measures and fit capability analysis, which can be used as a guideline to process design and process monitoring of the mating parts.