Abstract: The existing representative of the modular division methods are analyzed, and the four indicators of the principle of division are put forward. By comparison summary, the principles of modules division under the three-dimensional are brought out. Then, the existing methods for modules division are classified and analyzed. Moreover, the superiority and shortcoming of the existing methods are summarized and compared. Based on the analysis, a flexible modular division method has been concluded. Particularly emphasis the combination of engineering practice in the method——“The modular trans-formation of the existing product family”. The content and steps of the method are explained in the form of flow chart. Furthermore, gives a clear delineation of the specific module mathematical method. Finally, combining the engineering prac-tice of the typical crane parts——“beam”, the flexible method are verified.

Key words: Flexible method, Module partition, Pedigree clustering