Abstract
This paper introduces bending tool face, a new measurement with applications in directional drilling. The measurement is derived from two perpendicular bending moment sensors in the BHA and identifies the orientation of BHA bending with respect to gravity high side while drilling, both in rotating and sliding modes. The paper presents the underlying theory and motivation for the measurement, describes its implementation into a downhole MWD tool and shows measurement examples from field applications. Furthermore, the paper outlines the use of the data for directional calculations. The paper concludes with a discussion of applications in which the bending tool face information adds value, such as reducing uncertainty in casing exit applications and improving directional control in challenging 3-D well profiles. The discussion is supported with field results.
