Automatic Graphic Database System In Chemical Engineering Based On Parametric Technology

Aiming at the characteristics of chemical engineering profession, the paper establishes a chemical graphic database system, which uses various advanced developing technology of AutoCAD R14 and adopts the method of parametric design.Researching graphic database and parametric technology, analyzing the principle, virtue and disadvantage of various parametric design methods, the paper advances the method of function formal parameter to establish standard parts library in chemical procession. In the mean time, we achieve parametric drawing of chemical standard parts through analyzing the realization process of parametric drawing in detail. Developing the AutoCAD's internal and external database with Visual LISP language, using external database to save design parameters of chemical engineering standard parts, the paper realizes the creating from database to graphic database. At the same time, the paper completes the management of standard parts and sets up BOM automatically.In the course of the development of chemical engineering standard parts library, the author puts forth the concept of Universally Suitable Standard Part (USSP) which reduces the program's length, shortens the system scale and incarnates parametric technology adequately. Technologies of slide and Dialogue Box are utilized while the author develops the system interface .It is demonstrated through practice that the applications of these technologies have improved the efficiency of developing the chemical standard parts library, and makes the drawing fast.