Abstract: To test the justifiability of cutting pipe process with CNC machine, OpenGL and
3DSMax technologies are used to achieve the 3D dynamic presentation of process and cutting
result by driving the imported 3D static model with the parameters in OpenGL environment.
Compared with the traditional method which is based on collision detection to reproduce the
shape of pipe intersection, a new mathematical model is presented, and it has been proved to be
fast and accurate to calculate the intersection.

Key words: CNC pipe cutting machine, 3DSMax, OpenGL, 3D simulation, intersection