Abstract
In order to assure the quality of welding-assembly, A great deal body welding jigs are used during the all process of automobile body production. The structure of body welding jig have resemblance. It provides the technological support and achieved probability to develop the standardized design. The intelligent CAD technology based on knowledge, based on summing up design experience and field knowledge, can build a reused knowledge database and design planning model by abstracting, describing and maintaining, to offer some index method. By analyzing and describing function and structure character of the body welding jig, This paper builds knowledge base of typical body welding jig and introduces knowledge project into conventional CAD system, which will effectively support fast realization of intelligent CAD of body welding jig.