The present disclosure relates to roller cone drill bit journals with asymmetric ball races and extended friction races. The disclosure also relates to methods of forming such journals, and methods of finishing these journals to produce finished journals with symmetric ball races.

The present disclosure relates to roller cone drill bit journals with asymmetric ball races and extended friction races. The disclosure also relates to methods of forming such journals, and methods of finishing these journals to produce finished journals with symmetric ball races.

An advanced real-time drilling control system can comprise circuitry configured to continuously monitor, in real time, drilling performance of an electric drilling machine as the electric drilling machine drills a blasthole using a rotary tricone drill bit. The continuous monitoring can include continuously collecting, according to a predetermined sampling rate, drill performance data from one or more sensors of the electric drilling machine in real time. The circuitry can also be configured to adjust, in real time, pulldown pressure/rate and rotary speed of the rotary tricone drill bit of the electric drilling machine to optimize penetration rate of the rotary tricone drill bit based on the drill performance data and output of one or more machine learning operations applied to the drill performance data.

A downhole tool, for selectively reaming a wellbore or stabilizing drill string components within a wellbore, includes an elongate tool body adapted to receive reamer cartridges or stabilizer cartridges depending on the function desired. The reamer cartridges are radially insertable into corresponding pockets in the tool body, with each reamer cartridge having a reamer insert with an array of cutting elements. The reamer insert is disposed within a bushing and is rotatable relative thereto, about a rotational axis transverse to the longitudinal axis of the tool. However, the rotational axis is offset from the tool body axis, resulting in eccentric contact of the cutting elements with the wall of the wellbore, which in turn imparts rotation to the reamer insert when the tool is being moved axially through a wellbore without rotation. When the tool is to be used for stabilization, the reamer cartridges can be removed and replaced with stabilizer cartridges having stabilizer inserts with hard-faced stabilizer cones.

A roller bit for rock breaking by rotary cutting comprises: a bit body (1), a roller (2) and cutting teeth (3). An included angle β between a roller journal plane of the bit body and the roller on a bit axis has a range of 0°<β<90°, a journal offset S has a range of −D/2<S<D/2, wherein D represents a diameter of the bit. Inner row of teeth rings on the bit cuts a center of a borehole bottom, and each row of teeth ring is capable of scraping a borehole wall, and thus the bit has good effects of gauge protection and sidetracking.

A roller bit for rock breaking by rotary cutting comprises: a bit body (1), a roller (2) and cutting teeth (3). An included angle β between a roller journal plane of the bit body and the roller on a bit axis has a range of 0°<β<90°, a journal offset S has a range of −D/2<S<D/2, wherein D represents a diameter of the bit. Inner row of teeth rings on the bit cuts a center of a borehole bottom, and each row of teeth ring is capable of scraping a borehole wall, and thus the bit has good effects of gauge protection and sidetracking.

In accordance with embodiments of the present disclosure, a drilling system includes a roller cone drill bit having a roller cone and at least one antenna loop disposed in the roller cone for detecting magnetic or electromagnetic waves indicative of a target, a resistivity, or a boundary of the subterranean formation, man-made structure, or object. The drilling system may utilize the antenna loop to determine resistivity measurements of a subterranean formation through which the drill bit is being drilled. The location of the antenna in the roller cone may enable increased look-ahead and look-around measurements. In addition, the location of the antenna in the roller cone may facilitate anisotropic resistivity measurements to aid in steering the drill string into a desired portion of the subterranean formation.

In accordance with embodiments of the present disclosure, a drilling system includes a roller cone drill bit having a roller cone and at least one antenna loop disposed in the roller cone for detecting magnetic or electromagnetic waves indicative of a target, a resistivity, or a boundary of the subterranean formation, man-made structure, or object. The drilling system may utilize the antenna loop to determine resistivity measurements of a subterranean formation through which the drill bit is being drilled. The location of the antenna in the roller cone may enable increased look-ahead and look-around measurements. In addition, the location of the antenna in the roller cone may facilitate anisotropic resistivity measurements to aid in steering the drill string into a desired portion of the subterranean formation.

In accordance with embodiments of the present disclosure, systems and methods for utilizing hybrid mechanical-laser drilling tools, such as drill bits and hole-openers, are provided. Such drilling tools may include mechanical cutters in addition to laser cutting mechanisms designed to focus laser beams toward a subterranean formation. The mechanical cutters and laser cutting mechanisms may work in combination to advance a wellbore through the subterranean formation. The drilling tools may be controlled to vary the amount of energy output through the mechanical drilling via the cutters and through the laser-assisted drilling via the lasers.

In accordance with embodiments of the present disclosure, systems and methods for utilizing hybrid mechanical-laser drilling tools, such as drill bits and hole-openers, are provided. Such drilling tools may include mechanical cutters in addition to laser cutting mechanisms designed to focus laser beams toward a subterranean formation. The mechanical cutters and laser cutting mechanisms may work in combination to advance a wellbore through the subterranean formation. The drilling tools may be controlled to vary the amount of energy output through the mechanical drilling via the cutters and through the laser-assisted drilling via the lasers.