A cutter for a well construction tool has a cutting structure affixed to a substrate, which defines a monotonically decreasing diameter with respect to an axial distance from an interface between the cutting structure and the substrate. A shear surface formed in the cutting structure intersects a surface of the cutting structure between the interface and an apex of the cutting structure, and defines a smaller angle with respect to a reference than the cutting structure proximate the interface and a larger angle with respect to the reference than the cutting structure proximate the apex. The apex is rotationally symmetric about a centerline of the cutting structure in all rotational directions, and a radius of curvature of the apex is at most 75 percent of a diameter of the substrate. A well construction tool includes a tool body with at least one such cutter attached to the tool body.
A cutter for a well construction tool has a cutting structure affixed to a substrate, which defines a monotonically decreasing diameter with respect to an axial distance from an interface between the cutting structure and the substrate. A shear surface formed in the cutting structure intersects a surface of the cutting structure between the interface and an apex of the cutting structure, and defines a smaller angle with respect to a reference than the cutting structure proximate the interface and a larger angle with respect to the reference than the cutting structure proximate the apex. The apex is rotationally symmetric about a centerline of the cutting structure in all rotational directions, and a radius of curvature of the apex is at most 75 percent of a diameter of the substrate. A well construction tool includes a tool body with at least one such cutter attached to the tool body.
A reaming tool includes a reaming tool body configured to be coupled within a drill string or a string of drilling tools. A plurality of reaming blocks is attached to the reaming tool body at circumferentially spaced apart locations. At least one reaming block comprises at least a first row of gouging cutters and a second row of gouging cutters. The gouging cutters in the first row define a first profile. The gouging cutters in the second row define a second profile. The first row is rotationally ahead of the second row. The first profile at any longitudinal position along the at least one reaming block defines a larger reaming diameter than the second profile.
A reaming tool includes a reaming tool body configured to be coupled within a drill string or a string of drilling tools. A plurality of reaming blocks is attached to the reaming tool body at circumferentially spaced apart locations. At least one reaming block comprises at least a first row of gouging cutters and a second row of gouging cutters. The gouging cutters in the first row define a first profile. The gouging cutters in the second row define a second profile. The first row is rotationally ahead of the second row. The first profile at any longitudinal position along the at least one reaming block defines a larger reaming diameter than the second profile.
E21B 10/26 - Drill bits with leading portion, i.e. drill bits with a pilot cutterDrill bits for enlarging the borehole, e.g. reamers
B21K 5/04 - Making tools or tool parts, e.g. pliers drilling-tools or other tools for making or working on holes twisting-tools, e.g. drills, reamers
E21B 7/28 - Enlarging drilled holes, e.g. by counterboring
E21B 10/28 - Drill bits with leading portion, i.e. drill bits with a pilot cutterDrill bits for enlarging the borehole, e.g. reamers with non-expansible roller cutters
E21B 10/43 - Rotary drag type drill bits with teeth, blades or like cutting elements, e.g. fork-type bits, fish tail bits characterised by the arrangement of teeth or other cutting elements
E21B 10/55 - Drill bits characterised by wear resisting parts, e.g. diamond inserts the bit being of the rotary drag type, e.g. fork-type bits with preformed cutting elements
A drill bit includes a bit body; a plurality of gouging cutters rotatably mounted to the bit body so as to define a first profile; and a plurality of gouging cutters non-rotatably mounted to the bit body so as to define a second profile. The first profile is longitudinally ahead of the second profile in a direction of drilling of the drill bit by a selected distance.
E21B 10/43 - Rotary drag type drill bits with teeth, blades or like cutting elements, e.g. fork-type bits, fish tail bits characterised by the arrangement of teeth or other cutting elements
B23B 27/14 - Cutting tools of which the bits or tips are of special material
E21B 10/62 - Drill bits characterised by parts, e.g. cutting elements, which are detachable or adjustable
A drill bit includes a bit body; a plurality of gouging cutters rotatably mounted to the bit body so as to define a first profile; and a plurality of gouging cutters non-rotatably mounted to the bit body so as to define a second profile. The first profile is longitudinally ahead of the second profile in a direction of drilling of the drill bit by a selected distance.
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