SYSTEM AND PROCESS FOR DRILLING A PLANNED WELLBORE TRAJECTORY WITH A DOWNHOLE MUD MOTOR

摘要

The disclosure provides a system and process for drilling a subterranean wellbore. An embodiment includes a bottom-hole assembly for a downhole mud motor that incorporates an information sub, such as a measurement-while-drilling or logging-while-drilling tool, at a location below, or down-hole from, the mud motor. The assembly also includes a micronized bit-to-bend length, or a length between a forward end of the assembly's bearing mandrel and a fixed bend in the assembly's housing, of less than or equal to forty inches. The combination of the forward-located information sub and micronized bit-to-bend length allow the driller to rely on real-time data relating to conditions adjacent to the drill bit/bottom of the wellbore and take that real-time drilling data into account in steering the bit along a planned wellbore trajectory. Other embodiments are also disclosed.

主权项

1. A downhole assembly for drilling a planned wellbore trajectory, comprising:
a power assembly having a rotor activated by fluid transferred from a drill string; a transmission configured to transfer power from said rotor to an output shaft, said output shaft terminating in a bit box having a forward end; a bearing assembly radially and axially supporting said output shaft, said output shaft configured to drive a drill bit coupled to said output shaft via said bit box and an information sub, wherein said drill bit and said information sub each have forward and rearward ends, and wherein said rearward end of said drill bit attaches to said forward end of said information sub and said rearward end of said information sub attaches to said bit box; and a housing structure encompassing said power assembly, said transmission, and said bearing assembly, said housing structure having a fixed bend located a distance from said forward end of said bit box, wherein said distance is less than or equal to forty inches.