Recueil de mécanique
Volume 2, Numéro 1, Pages 103-111

Three-dimensional Functional Tolerancing Automated By Mt2m And Qualitative Tol

Authors : Djezouli Moulai-khatir. Said Hamou.


This paper deals with automatic three-dimensional (3D) functional tolerancing. A combination between the Minimum Transfer Modified Method (MT-2M) and qualitative tolerancing method for prismatic parts is developed. The Minimum Transfer Modified Method (MT-2M) is used for the recognition of functional surfaces. This technique lies in integrating the projections of surfaces of the parts under consideration along the three axes (X, Y and Z) and the contacts between these same surfaces in one table of matrix representation of the assembly. Then, the adequate qualitative tolerancing of the part under study is determined according to the number of functional conditions (CF), their types, and by using an ISO analysis. Finally, a 3D functional tolerancing (dimensioning and tolerancing) is then obtained in localization and orientation, to be installed on the drawings of different parts of the assembly. A manual application of this method to a simple example of assembly, and the software developed in this study are presented.


3D functional tolerancing; MT-2M ; Qualitative tolerancing method ; ISO analysis