The transformation of the pressure distribution and the air bearing force under the collective effect of radial velocity and skew angle was investigated during seeking process.

Before target-entering into a horizontal well or in the process of drilling horizontal section,to confirm the controlling range of deviation angle and azimuth of hole section is not only an important measure to guarantee target rate and trajectory control accuracy of the horizontal well but also one of the important contents in trajectory supervision of the horizontal well.

Due to the complicated calculation formula and trivial deduction course proposed by predecessor, this article derivated a new calculation formula for circular arc well section deviation angle and positional angle based on increment of coordinate identical equation.

The relationships between the critical density and critical salt content of drilling fluid and hole azimuth and deviation angle in horizontally isotropic and anisotropic formation respectively, are studied.

A mathematical model for numerical emulation of cutting forces in drilling using drills with indexable inserts based on oblique cutting theory combined with experimental approach is developed.

Using the general international FEM software ANSYS, the dynamic process of oblique cutting is simulated.

Basing on Merchant oblique cutting theory, dynamic force model for Ball end milling cutter is presented for avoiding the complicated engineering plasticity theory.

It uses dynamical tuning top to survey the directional of rotation angle velocity of the earth, and uses quartz accelerometer to survey the directional of acceleration of gravity, then to calculate the parameters such as the dip angle, azimuth angle, etc.