Abstract: A chimney CAD system is introduced which is developed by ObjectARX technology under the environment of AutoCAD. The system consists of three modules, that are pre-processing module, calculation module and post-processing module. Thus the integration is realized for the structure design of tube-in-tube chimney, calculation of reinforcingsteel configuration and drafting of engineering drawings. The system has some features such as friendly interface, easy operation, correct design and quick drafting, etc.

Key words: computer application, chimney CAD system, O-O programming, tube-in-tube chimney