In process plant projects, plant 3D CAD systems are used for basic and detail designs. Plant 3D CAD systems typically adopt the specification-driven modelling approach in which designers choose a modeling template called catalog for a plant item from a predefined modeling library, instantiate the selected template, and then placing it in the 3D design space. Therefore, equipment and materials catalog library should be constructed in order to support plant design using a plant 3D CAD system. The catalog typically consists of 3D shape, specifications, and ports which are generated by different systems. Therefore, it is necessary to develop a system which integrates 3D shape, specifications, and ports to create input data for the catalog library. In order to address this issue, a data structure for the catalog was first defined. A system to create catalog data by integrating 3D shape, specifications, and ports was then designed. According to the design, a prototype system was implemented and experiments using test cases were performed to verify the feasibility of the prototype system.