The bit side force of FG type anti-deviation device is almost never affected by drilling parameters, and the direction of bit side force continuously vary while drill string is rotating.

This paper makes a calculation of bit side force to the flexible pendulum stem and pendulum stem on the basis of vertial and horizontal bending theory, which, theoretically, shows that flexible pendulum stem has a better inclination correction effect than pendulum stem.

According to the model of calculating bit side force with the bending method,the applied force analysis software of BHA was developed with VB6.

Conventional mud logging in sidetracking horizontal wells.;

Study and application of the bit for sidetracking horizontal well;

The Directional Sidetracking Inside the φ139.7 mm Casing;

Drilling technology of GCP105-5 sidetrack horizontal well.;

Slim hole sidetracking and short-radius horizontal well drilling technology;

Study and application of sidetrack drilling technology;

Oriented case overshot for sidetrack drilling tech is a main component in down hole work-over operation.

To the situation of sidetrack drilling and slim hole of deep well and without using conventional perforated equipment for old wells in Qingxi oilfield, perforating tech without gun is selected to solve the completion problem and a set of operation way has been searched which raises successful ratio and accumulates experience for the future.