Abstract: The disclosure, in one aspect, provides a method of drilling a wellbore that includes features of drilling the wellbore using a drilling assembly that includes a drill bit that further includes a weight sensor and a torque sensor, determining weight-on-bit using measurements from the weight sensor and torque-on-bit using measurement from the torque sensor during drilling of the wellbore, obtaining measurements for rotational speed of the drill bit and rate of penetration of the drill bit during drilling of the wellbore, determining mechanical specific energy of the bottomhole assembly using the determined weight-on-bit, torque-on-bit and obtained rotational speed of the drill bit and the obtained rate of penetration of the drill bit, and altering a drilling a parameter in response to the determined mechanical specific energy.

Abstract: The disclosure, in one aspect, provides a method of drilling a wellbore that includes features of drilling the wellbore using a drilling assembly that includes a drill bit that further includes a weight sensor and a torque sensor, determining weight-on-bit using measurements from the weight sensor and torque-on-bit using measurement from the torque sensor during drilling of the wellbore, obtaining measurements for rotational speed of the drill bit and rate of penetration of the drill bit during drilling of the wellbore, determining mechanical specific energy of the bottomhole assembly using the determined weight-on-bit, torque-on-bit and obtained rotational speed of the drill bit and the obtained rate of penetration of the drill bit, and altering a drilling a parameter in response to the determined mechanical specific energy.

Abstract: A rotary drag bit includes a primary cutter row comprising at least one primary cutter and a multiple backup cutter group. The multiple backup cutter group comprises a first and second trailing cutter row, each comprising at least one cutter positioned to follow the at least one primary cutter. The rotary drag bit life is extended by the multiple backup cutter groups making the bit more durable and extending the life of the cutters. Further, the cutters of the multiple backup cutter group are configured to selectively engage a subterranean formation material being drilled, providing improved bit life and reduced stress upon the cutters. Other embodiments of rotary drag bits are provided.

Abstract: A rotary drag bit includes a primary cutter row comprising at least one primary cutter, and at least two additional cutters configured relative to one another. In one embodiment, the cutters are backup cutters of a backup cutter group located in respective first and second trailing cutter rows, oriented relative to one another, and positioned to substantially follow the at least one primary cutter. The rotary drag bit life is extended by the backup cutter group, making the bit more durable and extending the life of the cutters. In other of the embodiments, the cutters are configured to selectively engage a subterranean formation material being drilled, providing improved bit life and reduced stress upon the cutters. Still other embodiments of rotary drag bits include backup cutter configurations having different backrake angles and siderake angles, including methods therefor.

Abstract: A rotary drag bit includes a primary cutter row comprising at least one primary cutter, and at least two additional cutters configured relative to one another. In one embodiment, the cutters are backup cutters of a cutter group located in respective first and second trailing cutter rows, oriented relative to one another, and positioned to substantially follow the at least one primary cutter. The rotary drag bit life is extended by the backup cutter group, making the bit more durable and extending the life of the cutters. In other of the embodiments, the cutters are configured to selectively engage a subterranean formation material being drilled, providing improved bit life and reduced stress upon the cutters. Still other embodiments of rotary drag bits include backup cutter configurations having different backrake angles and siderake angles, including methods therefor.

Abstract: A rotary drag bit includes a primary cutter row comprising at least one primary cutter and a multiple backup cutter group. The multiple backup cutter group comprises a first and second trailing cutter row, each comprising at least one cutter positioned to follow the at least one primary cutter. The rotary drag bit life is extended by the multiple backup cutter groups making the bit more durable and extending the life of the cutters. Further, the cutters of the multiple backup cutter group are configured to selectively engage a subterranean formation material being drilled, providing improved bit life and reduced stress upon the cutters. Other embodiments of rotary drag bits are provided.