Methods and apparatus for monitoring wellbore tortuosity

Abstract

The present disclosure describes measuring bending moments within a drillstring or tool string to identify deflections (or 'dog-legs') within the string. In some systems, the bending moments a plurality of strain gauges. In some such systems the strain gauges will be arranged in a selected spacing around the circumference of the tool string, in many examples, at a common plane extending generally perpendicular to the longitudinal axis of the string proximate the strain gauges. The bending moments may be further evaluated to provide a measure of wellbore tortuosity. For example, the bending moments may be utilized to define a radius of curvature associated with the determined bending moments, which may be further correlated with a directional measurement to apply a direction to the bending moment, and therefore to the tortuosity an any given location. In many examples, the above measurements and determinations will be performed in essentially real time during a drilling operation; and will in some cases be used to perform remedial measures, where dictated.