A drill bit and method incorporate backup assemblies that limit depth of engagement of cutters with the formation. The backup assemblies dynamically adjust exposure relative to a cutting profile in response to downhole loading conditions. In an example, cutters are secured to the cone, nose, shoulder, and/or gage regions of the bit body. One or more backup assemblies are provided on the cone, nose, or shoulder region, and optionally, on the gauge region. A backup element on an outwardly facing end of the piston limits a depth of cut of one or more of the cutters. The backup element may be rigidly secured or rotatably secured to the piston. The piston may be biased outwardly to a neutral position aligned with or overexposed relative to the cutting profile.

A completions bit for use in a wellbore includes: a shank having a coupling formed at an upper end thereof; a body mounted to a lower end of the shank; and a cutting face forming a lower end of the bit. The cutting face includes: a blade protruding from the body; a tangentially oriented leading cutter mounted to a bearing face of the blade adjacent to a leading edge of the blade at an inner portion of the cutting face; and a radially oriented leading cutter mounted to the bearing face of the blade in proximity to the leading edge thereof at an outer portion of the cutting face.

A completions bit for use in a wellbore includes: a shank having a coupling formed at an upper end thereof; a body mounted to a lower end of the shank; and a cutting face forming a lower end of the bit. The cutting face includes: a blade protruding from the body; a tangentially oriented leading cutter mounted to a bearing face of the blade adjacent to a leading edge of the blade at an inner portion of the cutting face; and a radially oriented leading cutter mounted to the bearing face of the blade in proximity to the leading edge thereof at an outer portion of the cutting face.

A blade on a downhole drilling tool includes a blade body and a blade cover. The blade cover is pre-sintered and conforming to the blade outer shape. The blade cover is attached to the blade body. The blade cover includes a seamless connection between a cover leading face and a cover outer face to reduce wear on the outer face of the blade.

A blade on a downhole drilling tool includes a blade body and a blade cover. The blade cover is pre-sintered and conforming to the blade outer shape. The blade cover is attached to the blade body. The blade cover includes a seamless connection between a cover leading face and a cover outer face to reduce wear on the outer face of the blade.

A completions bit for use in a wellbore includes: a shank having a coupling formed at an upper end thereof; a body mounted to a lower end of the shank; and a cutting face forming a lower end of the bit. The cutting face includes: a blade protruding from the body; a tangentially oriented leading cutter mounted to a bearing face of the blade adjacent to a leading edge of the blade at an inner portion of the cutting face; and a radially oriented leading cutter mounted to the bearing face of the blade in proximity to the leading edge thereof at an outer portion of the cutting face.

A completions bit for use in a wellbore includes: a shank having a coupling formed at an upper end thereof; a body mounted to a lower end of the shank; and a cutting face forming a lower end of the bit. The cutting face includes: a blade protruding from the body; a tangentially oriented leading cutter mounted to a bearing face of the blade adjacent to a leading edge of the blade at an inner portion of the cutting face; and a radially oriented leading cutter mounted to the bearing face of the blade in proximity to the leading edge thereof at an outer portion of the cutting face.

An earth-boring tool for drilling a subterranean formation includes a bit body having a central axis and a cavity extending into the bit body from an outer surface thereof. A bearing element assembly may be mounted within the cavity. The bearing element assembly comprises a lower retaining member, an upper retaining member mounted over to the lower retaining member, the upper retaining member comprising an aperture formed therethrough, and a spherical bearing element disposed over the lower retaining member and extending through the aperture formed through the upper retaining member. The spherical bearing element is rotatable about three axes of rotation within the lower retaining member and the upper retaining member.

A PDC drill bit has a drill bit body and a blade. The blade is provided with cutting teeth. At least one cushion structure is rotatably connected to the drill bit body. The cushion structure makes contact with bottom hole rock, and the cushion structure swings in a direction opposite to the cutting of the drill bit. Alternatively, a cushioning portion on the cushion structure is eccentrically arranged. Under the action of the normal force of the bottom hole rock, the cushioning portion swings to an offset side. The cushion structure is detached from the bottom hole rock and is reset towards a free state under the action of a reset mechanism. Under complex motion conditions such as compound drilling and drilling into hard or non-uniform stratum conditions, the swing of the cushion structure absorbs an impact load and avoids impact damage to the cutting teeth.

A PDC drill bit has a drill bit body and a blade. The blade is provided with cutting teeth. At least one cushion structure is rotatably connected to the drill bit body. The cushion structure makes contact with bottom hole rock, and the cushion structure swings in a direction opposite to the cutting of the drill bit. Alternatively, a cushioning portion on the cushion structure is eccentrically arranged. Under the action of the normal force of the bottom hole rock, the cushioning portion swings to an offset side. The cushion structure is detached from the bottom hole rock and is reset towards a free state under the action of a reset mechanism. Under complex motion conditions such as compound drilling and drilling into hard or non-uniform stratum conditions, the swing of the cushion structure absorbs an impact load and avoids impact damage to the cutting teeth.