A superhard polycrystalline construction comprises a body of polycrystalline superhard material comprising a superhard phase, and a second phase dispersed in the superhard phase, the superhard phase comprising a plurality of inter-bonded superhard grains. The second phase comprises particles or grains that do not chemically react with the superhard grains, and/or do not inter-grow, and form between around 1 to 30 volume % or wt % of the body of polycrystalline superhard material.

In an embodiment, a method of fabricating a polycrystalline diamond compact is disclosed. The method includes sintering a plurality of diamond particles in the presence of a metal-solvent catalyst to form a polycrystalline diamond body; leaching the polycrystalline diamond body to at least partially remove the metal-solvent catalyst therefrom, thereby forming an at least partially leached polycrystalline diamond body; and subjecting an assembly of the at least partially leached polycrystalline diamond body and a cemented carbide substrate to a high-pressure/high-temperature process at a pressure to infiltrate the at least partially leached polycrystalline diamond body with an infiltrant. The pressure of the high-pressure/high-temperature process is less than that employed in the act of sintering of the plurality of diamond particles.

A reaming tool for enlarging an underground borehole comprises a plurality of cutter assemblies (251, 252, 253) distributed azimuthally around a longitudinal axis of the tool, wherein each cutter assembly comprises support structure bearing a sequence of cutters (211-214) with leading surfaces facing in a direction of rotation of the tool and the sequence of cutters extends axially along the tool from an axial end (202) of the tool with the cutters positioned at radial distances from the tool axis which progressively increase as the sequence extends away from the axial end of the tool. The cutter assemblies include guiding structure (261-264) which is positioned circumferentially ahead of the leading faces of cutters of the sequence on the assembly. This guiding structure is configured such that the outline of the guiding structure is able to coincide with at least part of the notional surface described by the cutting outline of the preceding cutter assembly as the tool rotates, without any part of the guiding structure projecting outside that notional surface. This stabilises the positioning of the rotating tool in the borehole.

A reaming tool for enlarging an underground borehole comprises a plurality of cutter assemblies (251, 252, 253) distributed azimuthally around a longitudinal axis of the tool, wherein each cutter assembly comprises support structure bearing a sequence of cutters (211-214) with leading surfaces facing in a direction of rotation of the tool and the sequence of cutters extends axially along the tool from an axial end (202) of the tool with the cutters positioned at radial distances from the tool axis which progressively increase as the sequence extends away from the axial end of the tool. The cutter assemblies include guiding structure (261-264) which is positioned circumferentially ahead of the leading faces of cutters of the sequence on the assembly. This guiding structure is configured such that the outline of the guiding structure is able to coincide with at least part of the notional surface described by the cutting outline of the preceding cutter assembly as the tool rotates, without any part of the guiding structure projecting outside that notional surface. This stabilises the positioning of the rotating tool in the borehole.

A cutting element comprises a supporting substrate exhibiting a three-dimensional, laterally elongate shape, and a cutting table of a polycrystalline hard material attached to the supporting substrate and comprising a non-planar cutting face. An earth-boring tool and method of forming an earth-boring tool are also described.

The invention relates to a tool (11) comprising a base element (2), which is a single-piece cast structure made of cast iron and comprising studs (3, 4) provided on the base element (2) by welding. The invention further relates to a method for forming such a tool and to the use of such a tool for forming secant walls.

The invention relates to a tool (11) comprising a base element (2), which is a single-piece cast structure made of cast iron and comprising studs (3, 4) provided on the base element (2) by welding. The invention further relates to a method for forming such a tool and to the use of such a tool for forming secant walls.

A drill bit for cutting a hole in a formation can have a longitudinal axis extending along a center of the drill bit. The drill bit can comprise a crown comprising at least one crown portion having a cutting face. A plurality of wear-resistant members can be embedded in the crown of the drill bit, wherein at least one wear-resistant member of the plurality of wear-resistant members extends to within 0.1 inches of the cutting face of the at least one crown portion.

A drill bit for cutting a hole in a formation can have a longitudinal axis extending along a center of the drill bit. The drill bit can comprise a crown comprising at least one crown portion having a cutting face. A plurality of wear-resistant members can be embedded in the crown of the drill bit, wherein at least one wear-resistant member of the plurality of wear-resistant members extends to within 0.1 inches of the cutting face of the at least one crown portion.

The invention relates to reamers used in downhole oil well drilling operations, particularly in reaming while drilling applications. Presented is a reamer having an interior channel which runs along an elongate axis of the entire body of the reamer, wherein there are openings along both ends of the reamer, exposing the interior channel. Additionally presented in the reamer are a plurality of paths extending parallel to the interior channel along the exterior of the body of the reamer, and running in a helical pattern along the entirety of the exterior of the body of the reamer. Disposed within the helical paths are a plurality of cutting inserts, which cutting inserts are enabled to provides a uniform cutting surface against a well bore, which preferably improves cutting action and reduces strain on the reamer.