Study on a Method for Tool Face Re-Orientation with Coiled Tubing Drilling

In order to solve the problems in tool face orientation with coiled tubing drilling, this paper presents a method to drill a directional well with a two-section design. Based on the theory of azimuth correcting on an inclined-plane and the skill of re-orientating the tool face, a two-arc directional design model was established, and the corresponding constraint equations set for trajectory deign could be solved using numerical iteration method, so as to finalize the well trajectory design which would meet the requirements of directional drilling. Calculation results from an actual well design showed that re-orientation of tool face could meet the requirements of directional drilling, and the well trajectory was designed as a smooth curve within the all constraints of the well. The study results concluded that the two-arc directional design model could meet the needs of directional drilling and the theoretic design was feasible in drilling practice, so problems with directional correction had been solved that would be useful to the drilling practice on location.