Patent ID: 8141658
Filing Date: 2012-03-27
Classification: E21B

Abstract:
1. A tilted drive sub for a conventional mud motor having a straight outer bearing housing, comprising: a replacement outer bearing housing, referred to as a tilted drive sub, for a mud motor, the replacement outer bearing housing having a top end and a bottom end, an outer diameter and an internal diameter, with internally threaded surfaces at each of two opposite extents thereof for incorporating the replacement outer bearing housing in the conventional mud motor; and wherein the internal diameter of the replacement outer bearing housing, or tilted drive sub, is on a predetermined center line and the outer diameter of the replacement outer bearing housing is also on a predetermined centerline, and wherein the center line of the internal diameter is offset at an angle from the center line of the outer diameter of the replacement outer bearing housing starting at a point near the top end of the housing, thereby producing a region of the internal diameter of the replacement outer bearing housing which is at an angle to the outer diameter, with the outer diameter of the replacement outer bearing housing remaining straight.