Abstract: A composite for cutting in subterranean formations comprises a cemented carbide substrate and a diamond layer adhered to a surface of the substrate. That surface includes a plurality of spaced apart ridges forming grooves therebetween. The diamond layer has a thickness greater than a depth of the grooves and occupies the grooves to interlock with the substrate. The diamond is comprised of a substantially uniform distribution of diamond particles having a grain size in a range of about 25-75 microns. The ridges are spaced radially inwardly from an outer periphery of the substrate, whereby the diamond layer includes an annular ring portion completely surrounding the plurality of ridges to provide radial reinforcement against the formation and propagation of cracks tending to occur in the vicinity of the ridges.

Abstract: A coring tool comprises a core cutting section and an actuating section disposed thereabove. The core cutting section includes axially telescoping outer and inner barrels. The inner barrel includes a jaw carrier which carries pivotable core-catching jaws normally covered along their radially inner sides by a driver sleeve. When the driver sleeve is raised by the actuator section the jaws are uncovered. Thereafter, the driver sleeve raises the jaw carrier to bring the jaws into contact with a stationary inclined jaw-deflecting surface to force the jaws laterally inwardly through the core. The actuator section relies upon fluid pressure to release for movement a vertically risible member which is mechanically lifted by a drill string to transmit vertical forces to the driver sleeve from a drill string.

Abstract: A rotary drill bit contains a plurality of cutting elements. Each cutting element includes a stud and a cutting disk mounted on the stud. The cutting disk comprises a substrate and a diamond layer bonded to the substrate. The cutting disk comprises a relief formed in an outer peripheral edge of the substrate and diamond layer at a formation-contacting point of the diamond layer, to form a pair of cutting points separated by the relief. The stud includes a channel aligned with the relief for conducting fluid to the relief to cool and clean the cutting points. The stud may include a fluid passage for conducting drilling fluid directly to the channel.

Abstract: A cutting element has a V-shaped diamond cutting face. The cutting element is formed from a single circular cutting blank by cutting the blank into segments, joining two identical ones of the segments, and truncating the joined segments.

Abstract: A cutting element comprises a stud and a composite bonded thereto. The composite comprises a substrate formed of cemented carbide, and a diamond layer bonded to the substrate. The interface between the diamond layer and substrate is defined by alternating ridges of diamond and cemented carbide which are mutually interlocked.

Abstract: A cutting element of the type which is pushed into a preformed hole of a drill bit by means of a pusher tool. The cutting element comprises a generally cylindrical stud having an inclined support face adjacent a forward end of the stud. A polycrystalline diamond substance is disposed on the support face. A non-circular tool recess is formed in the forward end of the stud and behind the support face and is configured to receive a pusher tool for confining pushing forces to the region of the recess as the cutting element is pushed into the preformed hole. The cutting element can also be rotated by the tool for repositioning the cutting element after installation, or loosening the cutting element to facilitate its removal.