Patent ID: 8648733
Filing Date: 2014-02-11
Classification: E21B

Abstract:
1. An electromagnetic telemetry gap sub comprising: (a) an electrically conductive housing having a body with a bore there-through and a threaded end; (b) an electrically conductive end coupling having a body with a bore there-through, an electronics cavity end, and an opposite threaded end threaded into the threaded end of the housing; (c) an insulated gap joint comprising a dielectric material in an annular gap between the threaded ends of the housing and end coupling such that the threaded ends are electrically insulated from each other; (d) a passage extending longitudinally through the end coupling body from the electronics cavity end to the threaded end; and (e) a conductor having an insulated covering and extending from the electronics cavity end, through the passage, through the gap joint and electrically connected to the housing, the conductor electrically connectable to an electromagnetic telemetry electronics package to serve as an antenna there-for.