Calculation on the boundary of horizontal well target with multiple control points

The mathematical definition of horizontal well target with multiple control points was set, so as to describe it accurately in the drilling design software. The vector algebra was used as the mathematical tool, and the external boundary curve of target was mathematically defined by using the normal plane coordinates of an arbitrary point on the target design axis. Then, a new concept of cuboid target with curved boundary was proposed and the calculation formula was also established for the external boundary curve of target. And finally, the drilling design software was applied in field. It is shown that the definition of cuboid target with curved boundary is reasonable and its calculation formula is accurate and can be easily presented in programming. Moreover, it was made possible to draw horizontal well targets accurately in horizontal projection, vertical projection, profile expansion and 3D diagrams.