A wellbore assembly includes a drill string, a drill bit, and a reamer assembly. The reamer assembly is coupled to the drill string uphole of the drill bit and includes a side cutter. The reamer assembly includes a spring that moves the side cutter from an extended position, in which the side cutter is retained by a portion of the reamer assembly against inward movement and in which the cutter defines a first drilling diameter greater than a drilling diameter of the drill bit, to a retracted position in which the portion of the reamer assembly has been broken by a shear force applied by the side cutter under a weight on bit applied against an inner component of the casing. In the retracted position, the side cutter is housed within the housing and defines a drilling diameter equal to or less than the drilling diameter of the drill bit.

At least one labyrinth seal assembly is disposed within a roller cutter of a roller reamer. A first labyrinth seal assembly of a roller cutter is positioned toward a first pillow block of a cutter cartridge that includes the roller cutter. A bearing shaft of the cutter cartridge extends through an inner channel of the roller cutter. The cutter cartridge is retained in an axial recess of a tool body of the roller reamer via a compound and separate wedging of each of the two pillow blocks into a same axial recess by means of a shaped wedge particularly specialized to improve secure coupling of the assembly and reduce rattling of components. Each pillow block is rotatably coupled to the bearing shaft at an opposing end of the roller cutter.

At least one labyrinth seal assembly is disposed within a roller cutter of a roller reamer. A first labyrinth seal assembly of a roller cutter is positioned toward a first pillow block of a cutter cartridge that includes the roller cutter. A bearing shaft of the cutter cartridge extends through an inner channel of the roller cutter. The cutter cartridge is retained in an axial recess of a tool body of the roller reamer via a compound and separate wedging of each of the two pillow blocks into a same axial recess by means of a shaped wedge particularly specialized to improve secure coupling of the assembly and reduce rattling of components. Each pillow block is rotatably coupled to the bearing shaft at an opposing end of the roller cutter.

A roller reamer for downhole operations in boreholes, such as are drilled for oil and/or natural gas production, or as injection wells. An elongated main body has preferably three circumferentially spaced pockets. A roller assembly is preferably disposed in each pockets, the roller rotating in roller blocks at each end of the roller disposed within the roller blocks. Mating locking profiles, such as dovetails, lock the roller blocks within the pockets, as the roller blocks are moved longitudinally into the locking profiles, preventing any radially outward movement of the roller assembly. The roller assembly is prevented from longitudinal movement within the pockets by lock blocks also positioned within the pockets.

A roller reamer for downhole operations in boreholes, such as are drilled for oil and/or natural gas production, or as injection wells. An elongated main body has preferably three circumferentially spaced pockets. A roller assembly is preferably disposed in each pockets, the roller rotating in roller blocks at each end of the roller disposed within the roller blocks. Mating locking profiles, such as dovetails, lock the roller blocks within the pockets, as the roller blocks are moved longitudinally into the locking profiles, preventing any radially outward movement of the roller assembly. The roller assembly is prevented from longitudinal movement within the pockets by lock blocks also positioned within the pockets.

The multifunction wellbore conditioning tool (100, 200, 300) is installed in the bottom hole assembly of a drill string and performs the functions of a cutting tool, keyseat wiper, roller reamer, keyseat wiper, and stabilizer during drilling operations, precluding the need for multiple different tools in the drill string. The tool (100, 200, 300) has a working sleeve (114, 214, 314) captured concentrically on the driveshaft (102, 202, 302) between opposed spring sets (134, 136; 234, 236; 334, 336). The sleeve (114, 214, 314) remains rotationally stationary about the rotating driveshaft (102, 202, 302) when in its central or neutral position on the driveshaft (102, 202, 302). When the sleeve (114, 214, 314) shifts axially on the driveshaft (102, 202, 302) it engages a clutch mechanism that allows it to rotate with the driveshaft (102, 202, 302) so that the rotating working sleeve (114, 214, 314) conditions the borehole.

The multifunction wellbore conditioning tool (100, 200, 300) is installed in the bottom hole assembly of a drill string and performs the functions of a cutting tool, keyseat wiper, roller reamer, keyseat wiper, and stabilizer during drilling operations, precluding the need for multiple different tools in the drill string. The tool (100, 200, 300) has a working sleeve (114, 214, 314) captured concentrically on the driveshaft (102, 202, 302) between opposed spring sets (134, 136; 234, 236; 334, 336). The sleeve (114, 214, 314) remains rotationally stationary about the rotating driveshaft (102, 202, 302) when in its central or neutral position on the driveshaft (102, 202, 302). When the sleeve (114, 214, 314) shifts axially on the driveshaft (102, 202, 302) it engages a clutch mechanism that allows it to rotate with the driveshaft (102, 202, 302) so that the rotating working sleeve (114, 214, 314) conditions the borehole.

Bottom hole assemblies for deploying fabric can include: a body configured to be attached to a drill pipe; a control tube disposed inside the body at a position controlled by engagement of a cam with a continuous guide path; a set tube, the set tube and the body together defining a pressure chamber with the body defining an inlet port extending between the interior cavity and pressure chamber, the set tube movable between a rolling position and a reaming position; a reamer assembly with at least one first articulated arm with extending between first attachment point on the body and the set tube; and a roller assembly with: at least one second articulated arm extending between the set tube and a second attachment point on the body; and a roller positioned at a joint of each second articulated arm.

A debris removal system includes: a drill pipe disposed within a borehole including a threaded portion disposed longitudinally above a bottom hole assembly (BHA). The threaded portion includes at least one spiral notch that wraps around the drill pipe. An outer diameter of the threaded portion of the drill pipe remains constant throughout a longitudinal length of the threaded portion.

A simple centralizer, comprising a mandrel extending between box couplings, a rotor receiving surface between the box couplings, a shoulder on the mandrel defining a first end of the rotor receiving surface; and a collar receiving surface on a second end of the rotor receiving surface. The collar receiving surface may be unthreaded. In use, a collar is press fit on to the collar receiving surface.