Abstract: A bit used in a downhole environment has an active element that is movable relative to the bit. The bit is rotated in the downhole environment, and at least one downhole parameter is measured. The at least one downhole parameter is compared against a target parameter value, and when the at least one downhole parameter is beyond a threshold value of the target parameter value, the active element is selectively relative to the bit. Movement of the active element alters the proportion of the weight on the active element as compared to the other cutting structure of the bit. Changing the proportion of weight can be used to reduce the depth of cut of the cutting structure and to reduce or eliminate motor stall or stick-slip behavior.

Abstract: Milling systems, tools, and methods include using a mill with secondary attrition system to re-mill cuttings and other debris away from the face of the mill. The secondary attrition system may be located uphole of the mill may be used to stage conditioning and re-sizing of debris. After debris is generated by the mill, the secondary attrition system may re-mill the debris to a finer size before allowing the debris to pass out of the sleeve. The debris may be re-milled by secondary cutting elements while within an annular gap positioned radially between the sleeve and a drive shaft for the mill. The annular gap may have a variable width as a result of a tapered outer surface of the drive shaft and/or a tapered inner surface of the sleeve. The variable width may cause debris to be re-milled into increasingly finer sizes.

Abstract: Milling systems, tools, and methods include using a mill with secondary attrition system to re-mill cuttings and other debris away from the face of the mill. The secondary attrition system may be located uphole of the mill may be used to stage conditioning and re-sizing of debris. After debris is generated by the mill, the secondary attrition system may re-mill the debris to a finer size before allowing the debris to pass out of the sleeve. The debris may be re-milled by secondary cutting elements while within an annular gap positioned radially between the sleeve and a drive shaft for the mill. The annular gap may have a variable width as a result of a tapered outer surface of the drive shaft and/or a tapered inner surface of the sleeve. The variable width may cause debris to be re-milled into increasingly finer sizes.

Abstract: Milling systems, tools, and methods include using a mill with secondary attrition system to re-mill cuttings and other debris away from the face of the mill. The secondary attrition system may be located uphole of the mill may be used to stage conditioning and re-sizing of debris. After debris is generated by the mill, the secondary attrition system may re-mill the debris to a finer size before allowing the debris to pass out of the sleeve. The debris may be re-milled by secondary cutting elements while within an annular gap positioned radially between the sleeve and a drive shaft for the mill. The annular gap may have a variable width as a result of a tapered outer surface of the drive shaft and/or a tapered inner surface of the sleeve. The variable width may cause debris to be re-milled into increasingly finer sizes.

Abstract: An expandable tool includes a body and a recess extending at least partially through the body from an outer radial surface of the body. A spline insert may be at least partially positioned in the recess and coupled to the body. The spline insert may include a single spline or multiple splines. A cutter block or other expandable member may be at least partially positioned in the recess. The cutter block or other expandable member may include a spline on a side surface thereof, which spline may be engaged with the one or more splines of the spline insert. Engagement between one or more splines of the spline insert and spline of the cutter block or other expandable member may allow the expandable member to move radially outward from a retracted position to an expanded position, and vice versa.

Abstract: An expandable tool includes a body and a recess extending at least partially through the body from an outer radial surface of the body. A spline insert may be at least partially positioned in the recess and coupled to the body. The spline insert may include a single spline or multiple splines. A cutter block or other expandable member may be at least partially positioned in the recess. The cutter block or other expandable member may include a spline on a side surface thereof, which spline may be engaged with the one or more splines of the spline insert. Engagement between one or more splines of the spline insert and spline of the cutter block or other expandable member may allow the expandable member to move radially outward from a retracted position to an expanded position, and vice versa.

Abstract: An expandable tool includes a body and a recess extending at least partially through the body from an outer radial surface of the body. A spline insert may be at least partially positioned in the recess and coupled to the body. The spline insert may include a single spline or multiple splines. A cutter block or other expandable member may be at least partially positioned in the recess. The cutter block or other expandable member may include a spline on a side surface thereof, which spline may be engaged with the one or more splines of the spline insert. Engagement between one or more splines of the spline insert and spline of the cutter block or other expandable member may allow the expandable member to move radially outward from a retracted position to an expanded position, and vice versa.

Abstract: An underreamer for increasing the diameter of a bore. The underreamer includes a substantially cylindrical body. A mandrel may extend axially through the body. One or more cutter blocks are movably coupled to the body. A ratio of a height of the cutter block to a diameter of the body is between about 0.35:1 and about 0.50:1.

Abstract: An underreamer for increasing the diameter of a bore. The underreamer includes a substantially cylindrical body having an axial bore therein. A mandrel may extend axially through the axial bore. One or more cutter blocks are movably coupled to the body. A ratio of a height of the cutter block to a diameter of the body is between about 0.35:1 and about 0.50:1.

Abstract: A downhole tool for increasing a cross-sectional area of a wellbore is provided. The downhole tool may include a first drilling assembly including a first reaming tool for selectively increasing the cross-sectional area of the wellbore. A first ball seat may receive a first ball. At least one of the first ball seat and the first ball may deform to allow the first ball to pass through the first ball seat when a predetermined pressure is applied thereto. A first piston may be coupled to the first ball seat. The first ball seat and the first piston may stroke when the first ball is received within the first ball seat, thereby actuating the first reaming tool between an active state and an inactive state.

Abstract: An underreamer for increasing a diameter of a wellbore. The underreamer includes a body having an axial bore extending at least partially therethrough. An annular sleeve may be coupled to the body and adapted to move with respect to the body. The sleeve may include a plurality of grooves formed therein that are circumferentially offset from one another. A pin may be coupled to the body. The sleeve may be adapted to move with respect to the pin to transition the pin from a first groove in the sleeve to a second groove in the sleeve. The sleeve may be in a first axial position with respect to the body when the pin is positioned in the first groove, and the sleeve may be in a second axial position with respect to the body when the pin is positioned in the second groove. The underreamer also includes one or more cutter blocks. The radial cutting diameter of the one or more cutter blocks depends on the axial position of the one or more cutter blocks and may be determined therefrom.

Abstract: Milling systems, tools, and methods include using a mill with secondary attrition system to re-mill cuttings and other debris away from the face of the mill. The secondary attrition system may be located uphole of the mill may be used to stage conditioning and re-sizing of debris. After debris is generated by the mill, the secondary attrition system may re-mill the debris to a finer size before allowing the debris to pass out of the sleeve. The debris may be re-milled by secondary cutting elements while within an annular gap positioned radially between the sleeve and a drive shaft for the mill. The annular gap may have a variable width as a result of a tapered outer surface of the drive shaft and/or a tapered inner surface of the sleeve. The variable width may cause debris to be re-milled into increasingly finer sizes.

Abstract: Milling systems, tools, and methods include using a mill with a barrier to promote re-circulation of debris and cuttings to the face of the mill. The face of the mill may include cutting elements. A barrier may obstruct the flow of cuttings and debris away from the face to re-circulate the cutting and debris to promote re-milling of the cuttings and debris by the cutting elements of the face of the mill. The barrier may include a hydraulic barrier formed by fluid expelled from nozzles in or above the mill. A secondary attrition system uphole of the mill may also be used to stage conditioning and re-sizing of cuttings and debris. After debris and cuttings pass through the barrier, the secondary attrition system may re-mill the cuttings and debris to a finer size before allowing the cuttings and debris to pass into the wellbore annulus for transport to the surface.

Abstract: An expandable tool includes a body and a recess extending at least partially through the body from an outer radial surface of the body. A spline insert may be at least partially positioned in the recess and coupled to the body. The spline insert may include a single spline or multiple splines. A cutter block or other expandable member may be at least partially positioned in the recess. The cutter block or other expandable member may include a spline on a side surface thereof, which spline may be engaged with the one or more splines of the spline insert. Engagement between one or more splines of the spline insert and spline of the cutter block or other expandable member may allow the expandable member to move radially outward from a retracted position to an expanded position, and vice versa.

Abstract: A downhole tool may include a body with a flow channel therethrough. The flow channel may be an outer flow channel that is radially outward relative to an inner flow channel and/or a rod. The rod or inner flow channel may act as a valve to allow flow within the outer flow channel. A plunger may be positioned within the body and acted upon by fluid in the inner flow channel or the rod. The plunger may move from a first position that restricts fluid flow from the outer flow channel to a chamber in the body to a second position that allows fluid flow from the outer flow channel to the chamber in the body at least partially in response to fluid flowing through the inner flow channel. An expandable member, such as a cutting tool or isolation tool, may be movably coupled to the body.

Abstract: An underreamer for increasing the diameter of a bore. The underreamer includes a substantially cylindrical body. A mandrel may extend axially through the body. One or more cutter blocks are movably coupled to the body. A ratio of a height of the cutter block to a diameter of the body is between about 0.35:1 and about 0.50:1.

Abstract: An underreamer for increasing the diameter of a bore. The underreamer includes a substantially cylindrical body having an axial bore therein. A mandrel may extend axially through the axial bore. One or more cutter blocks are movably coupled to the body. A ratio of a height of the cutter block to a diameter of the body is between about 0.35:1 and about 0.50:1.

Abstract: An underreamer for increasing a diameter of a wellbore. The underreamer includes a body having an axial bore extending at least partially therethrough. An annular sleeve may be coupled to the body and adapted to move with respect to the body. The sleeve may include a plurality of grooves formed therein that are circumferentially offset from one another. A pin may be coupled to the body. The sleeve may be adapted to move with respect to the pin to transition the pin from a first groove in the sleeve to a second groove in the sleeve. The sleeve may be in a first axial position with respect to the body when the pin is positioned in the first groove, and the sleeve may be in a second axial position with respect to the body when the pin is positioned in the second groove. The underreamer also includes one or more cutter blocks. The radial cutting diameter of the one or more cutter blocks depends on the axial position of the one or more cutter blocks and may be determined therefrom.

Abstract: A downhole tool for increasing a cross-sectional area of a wellbore is provided. The downhole tool may include a first drilling assembly including a first reaming tool for selectively increasing the cross-sectional area of the wellbore. A first ball seat may receive a first ball. At least one of the first ball seat and the first ball may deform to allow the first ball to pass through the first ball seat when a predetermined pressure is applied thereto. A first piston may be coupled to the first ball seat. The first ball seat and the first piston may stroke when the first ball is received within the first ball seat, thereby actuating the first reaming tool between an active state and an inactive state.