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 reamer for use in underground drilling back-reaming operations. The reamer comprises a body comprising a plurality of pockets. The pockets are configured such that an arm, a rolling cutter, and a retainer may fit within each of the pockets. Each of the rolling cutters is connected to each of the arms via a spindle. The rolling cutters are held on the spindle and connected to each of the pockets via a retainer. Each of the arms is secured to each of the pockets via a plurality of fasteners. A mechanical lock is used to secure at least one of the fasteners in place. Each of the arms comprises a grease passage and a pressure compensation system. The rolling cutters are replaceable with rolling cutters of like size or rolling cutters of different sizes and shapes.

A reamer for use in underground drilling back-reaming operations. The reamer comprises a body comprising a plurality of pockets. The pockets are configured such that an arm, a rolling cutter, and a retainer may fit within each of the pockets. Each of the rolling cutters is connected to each of the arms via a spindle. The rolling cutters are held on the spindle and connected to each of the pockets via a retainer. Each of the arms is secured to each of the pockets via a plurality of fasteners. A mechanical lock is used to secure at least one of the fasteners in place. Each of the arms comprises a grease passage and a pressure compensation system. The rolling cutters are replaceable with rolling cutters of like size or rolling cutters of different sizes and shapes.

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.

Embodiments of a reamer of the present invention generally include a substantially tubular body sub, a substantially planar base plate having one or more receiving cavities disposed therein, one or more gussets, a fluid chamber, and a plurality of leg/cone assemblies having a leg end and a cone end; wherein the base plate is disposed around the body sub and stabilized by the gussets, and each leg end comprises an exterior surface geometry complementary to the interior surface geometry of a base plate receiving cavity and is insertable into and affixable therein. The receiving cavities are constructed in defined locations and orientations in the base plate and the leg/cone assemblies are precisely formed such that insertion of the leg end into the receiving cavity accurately and precisely disposes the cutting component about the reamer. Embodiments of methods of providing and using an apparatus of the present invention are also provided.

A drilling string stabilizer tool comprises a cylindrical body and a plurality of stabilizer blades machined as an integral component forming in this way a monolithic blade stabilizer tool. The stabilizer blades have an elongated shape and are aligned in the direction of the axis of the cylindrical body. The blades are disposed in such a way to result in an almost constant flow-by-area.

A downhole mud motor is formed of plural housings containing at least a drive section and a transmission section. At least a housing of the plural housings has a longitudinal axis and incorporates a reaming section with one or more rotary reamers. Each of the one or more rotary reamers is mounted in a respective pocket for rotation about a transverse axis relative to the longitudinal axis of the housing.

A downhole mud motor is formed of plural housings containing at least a drive section and a transmission section. At least a housing of the plural housings has a longitudinal axis and incorporates a reaming section with one or more rotary reamers. Each of the one or more rotary reamers is mounted in a respective pocket for rotation about a transverse axis relative to the longitudinal axis of the housing.

An apparatus and method for alleviating spiraling in boreholes is disclosed. The apparatus includes a sub, which adjusts the length of the bottom-hole assembly in response to tension/compression, flexural bending and/or torque measurements made above and below the reamer so that the drill bit and the reamer cut at the same depth rate. The sub is connected between the drill bit and the reamer. The apparatus further includes measurement devices disposed on the bottom-hole assembly above and below the reamer, which are capable of measuring the tension/compression, flexural bending and torque in the bottom-hole assembly. The method includes use of a data processor, which determines which operational output signals to supply to the sub in order to adjust its length and thereby accomplish the desired drilling rates.