Abstract: Some embodiments of the present invention generally provide an apparatus that may be used in a coiled tubing drillstring and that can switch between effectively straight drilling and curved drilling without halting drilling. Methods for steering a coiled tubing drillstring are also provided. In one embodiment, an apparatus for use in drilling a wellbore is provided. The apparatus includes a mud motor; a housing; an output shaft; and a clutch actuatable between two positions. The clutch is configured to rotationally couple the mud motor to the output shaft when the clutch is in a first position as a result of fluid being injected through the clutch at a first flow rate, and rotationally couple the output shaft to the housing when the clutch is in a second position as a result of fluid being injected through the clutch at a second flow rate.

Abstract: A compact, robust, wear resistant, and high performance electrically insulating gap sub for use with borehole EM Telemetry is disclosed. In one embodiment, the gap sub may include an externally threaded mandrel separated from an internally threaded housing by a dielectric material. Additionally, some embodiments may include an external gap ring for separating the upper and lower electrical halves of the sub which offers structural support, acts as the primary external seal, and provides an abrasion resistant non-conductive length on the exterior. Some embodiments may include torsion pins to prevent the possible unscrewing of the dielectric filled threaded sections should the dielectric material become damaged or weakened.

Abstract: Methods, apparatus and articles of manufacture are provided for a configurable downhole tool. The downhole tool includes a plurality of devices each of which is configured for one or more functions. At some point during operation (e.g., during system initialization), the presence of each device disposed on the downhole tool is detected. Each device may then begin performing its respective function or functions. For example, some devices may be configured to collect environmental data while the tool is disposed in a wellbore. In one embodiment, the collected data is provided to a transceiver. The transceiver then transmits the data from the downhole tool to some remove receiving unit, which may be located at the surface of the wellbore.

Abstract: A non-locking tapered plug valve is provided which prevents taper locking of the plug member by ensuring against pressure responsive plug movement toward the small extremity thereof due to positive or negative hydraulic pressure transients. The chambers at each axial extremity of the plug member are of such volumetric relation during positive pressure transients that the chamber at the small extremity of the plug reaches equilibrium with flow passage pressure before the chamber at the large extremity of the plug member thus ensuring that any pressure responsive resultant force acting on the plug member is directed toward its large extremity. To avoid taper locking during a negative pressure transient, an equalization passage with a check valve is provided to permit unidirectional flow from the large extremity of the valve chamber to the main flow passage.