A drill bit for cutting formation comprises a bit body, a plurality of cutters, a plurality of blades with pockets to accommodate the cutters respectively. Each of the plurality of cutters has an ultra-hard layer, two side facets extending obliquely inward from the substrate to a top surface of the ultra-hard layer, a convex portion between the two side facets. The convex portion comprises a transition surface and the transitional surface is convex as it extends between adjacent the two side facets. The curvature of the transitional surface varies along the cutter axis with the curvature at the cutting edge larger than the curvature of the cutter circumferential surface.

A drill bit for cutting formation comprises a bit body, a plurality of cutters, a plurality of blades with pockets to accommodate the cutters respectively. Each of the plurality of cutters has an ultra-hard layer, two side facets extending obliquely inward from the substrate to a top surface of the ultra-hard layer, a convex portion between the two side facets. The convex portion comprises a transition surface and the transitional surface is convex as it extends between adjacent the two side facets. The curvature of the transitional surface varies along the cutter axis with the curvature at the cutting edge larger than the curvature of the cutter circumferential surface.

A cutting bit includes a body, a plurality of blades, and at least one ultrahard insert cast directly into at least one of the plurality of blades. The ultrahard insert is positioned with a rear face directly contacting the blade.

A cutting bit includes a body, a plurality of blades, and at least one ultrahard insert cast directly into at least one of the plurality of blades. The ultrahard insert is positioned with a rear face directly contacting the blade.

The present disclosure provides a cutting head adapted to removably couple to a bit body of a drill bit assembly. The cutting head includes a leading cutting tip for cutting into earth and a trailing receiving portion for receiving a second end of the bit body in an internal cavity defined by the trailing receiving portion to allow the cutting head to be removably coupled to the second end of the bit body.

A polycrystalline diamond drill bit for percussion drilling, in small hole high silica ground is disclosed which has a cutting face having an inner flat face and an outer beveled peripheral surface, a number of first polycrystalline diamond tipped inserts having a first diameter inserted into the inner flat face and the outer beveled peripheral surface, and a number of second polycrystalline diamond tipped inserts having a second diameter inserted into the inner flat face, with the second diameter being different than the first diameter. The cutting angle and the radius of the tip of each insert in addition to the diameter of the inserts, provide for use of a machine thrust pressure and machine torque pressure at low ranges when the PCD bits are used in percussion drilling. The percussion drilling, with larger bits, may be used for rotary oil drilling, and operating at a machine thrust and torque of less than 20 Bar.

A polycrystalline diamond drill bit for percussion drilling, in small hole high silica ground is disclosed which has a cutting face having an inner flat face and an outer beveled peripheral surface, a number of first polycrystalline diamond tipped inserts having a first diameter inserted into the inner flat face and the outer beveled peripheral surface, and a number of second polycrystalline diamond tipped inserts having a second diameter inserted into the inner flat face, with the second diameter being different than the first diameter. The cutting angle and the radius of the tip of each insert in addition to the diameter of the inserts, provide for use of a machine thrust pressure and machine torque pressure at low ranges when the PCD bits are used in percussion drilling. The percussion drilling, with larger bits, may be used for rotary oil drilling, and operating at a machine thrust and torque of less than 20 Bar.

A cutting assembly for use in a drill bit has an ovoid insert including an ultrahard material. The ovoid insert is cast in a matrix such that the matrix surrounds at least part of the ovoid insert, limiting movement of the ovoid insert. Material is removed from the top surface and sidewall of the cutting assembly to produce a cutting edge.

A cutting assembly for use in a drill bit has an ovoid insert including an ultrahard material. The ovoid insert is cast in a matrix such that the matrix surrounds at least part of the ovoid insert, limiting movement of the ovoid insert. Material is removed from the top surface and sidewall of the cutting assembly to produce a cutting edge.

A strike tip for a pick tool is provided. The strike tip comprises a strike structure comprising a super-hard material and a substrate comprising cemented carbide material, the substrate being joined to the strike structure at an interface. The strike tip has rotational symmetry about a main central axis. The strike structure has a planar apex area and, on a plane on which the main central axis lies, a convex curved side wall extends between the planar apex area and the substrate.