(1) The concepts of oblique cut index and anisotropy index and comprehensive cutting readiness anisotropy index of drilling rigs have led to the general Roundup formula of formation natural slope force suitable for drilling rigs' actual drill bits, volume breakage and surface breakage. And simplified form; using the drilling-drilling-cone method of the drilling machine to derive the formulas of the stratigraphic and oblique forces and the azimuthal forces of the stratum in directional drilling, which provides a basis for the analysis of the formation forces for the orientation and orbit control of the drilling machine. After verification, the theoretical analysis results are in good agreement with the actual drilling.
(2) Based on the proposed new concept, the critical formation dip angle equation was found, which provided a preliminary quantitative explanation for judging the trend of the drill bit.
(3) Orientation and small formations have flutter force and formation in-position force, scoop well angle, weight on bit, formation dip angle, drilling anisotropy index, formation anisotropy index, well azimuth and formation The upward azimuth force may also be a reduced azimuth force. Under normal circumstances, the stratum changing well tilting force causes the drill bit trajectory to move closer to the formation normal, and the stratum changing azimuth force brings the wellbore azimuth closer to the stratum. When the wellbore of the drilling rig is consistent with the orientation of the formation, the variable azimuth force of the formation is zero.
(4) The formation force of a drilling machine is directly proportional to the weight on bit. Increasing the weight on bit will increase the formation force significantly.