Abstract: The method of value intercalation is extensively applied in petroleum engineering and it is different from ordinary mathematical value intercalation. According to the drilling design and the principles of wellbore track formation, the three intercalation models-cylindrical spiral, special circular arc and natural parameters-were figured out. The theoretical analysis and calculation examples indicated that these intercalation equations are suitable for internal intercalation and external detection and it can satisfy the need of various intercalation calculations on wellbore track.