[en] The progress of electronic computers is surprising indeed. Even a problem so complicated as impossible for man to calculate now can be solved with ease by a computer. However, in the case of a work where human factors are involved, such as design and drafting, computers are no much for man. The design and drafting are fundamentally empirical, but not clarified in procedure and logic, such as calculation. The CAD system makes the most of the faculties of both man and computer in combination for the design of the piping of power plants. (author)