Study on the Quality of Body Assembly Based on Tolerance Analysis by Linearized Method

The tolerance analysis by linearized method could be used to confirm the tolerances of the different parts of body assembly, and to ensure the accuracy of the gap and flush of body-in-white assembly. Key parts and dimensions could be found by this way. The process capacity target, PPK, and I-MR control charts are considered as the way to control the quality of parts. The forward direction quality control model for body assembly is constructed by those two methods above, and that means the targets of the dimensions of body assembly could be reflected on dimensions of parts, and should be quantifyed. Based on the forward direction model, precision of parts is supervised, and this means it provides a fact to rectify parts. And this is reverse direction quality control model. Considering Time series of the parts and assembly, Bayesian theory was used to modify the datas, and also Correlation Coefficient could be calculated, in order to know the exact Contributions parts was made to the quality of body assembly.