Comparative Statistical Analysis of Test Parts Manufactured in Production Environments

Estimating error uncertainties arising in production parts is not a well-understood process. An approach to estimate these uncertainties was developed in this study. Machine tool error components were measured on a three-axis vertical machining center. Multiple parts were produced on the measured machining center then measured on a coordinate measuring machine. Uncertainty models for hole-center to hole-center lengths and orthogonalities were developed using measured machine tool errors. These estimated uncertainties were compared against measured uncertainties. The main conclusion from the study is that the Law of Propagation of Uncertainties can be used to estimate machining uncertainties.