Abstract: A PDC cutter includes a diamond table layer and an underlying substrate layer. A cap structure for the PDC cutter includes a first portion overlying, but not attached to, a front face of the diamond table layer and a second portion extending perpendicularly from the first portion which is overlying and attached to an outer peripheral surface of the underlying substrate layer.

Abstract: An ice auger covering apparatus includes a housing that has a bottom wall and a peripheral wall that is attached to and extends upwardly from the bottom wall. The housing has a break therein so that the housing includes a first portion and a second portion. The first and second portions are hingedly coupled together and biased toward each other in a closed position. A plurality of blade engaging members is provided. Each of the blade engaging members is configured to receive an edge of a bottom blade. The blade engaging members are attached to an inner surface of the peripheral wall. A pointed end of the ice auger is extendable into the housing and bottom blades of the auger engaged with the blade engaging members so that the housing covers the pointed end and the bottom blades.

Abstract: A drill bit stabilizing system comprising a body member having an axis and at least one recess formed in the body member housing at least one stabilizing member when in a first retracted position. The stabilizing member is positionable along a diagonal angle with the axis to a second extended operating position which extends downward and outward relative to the main body to selectively engage the surface of a pilot bore hole wall during a drilling operation so as to stabilize an under gauge drill bit used in association with the stabilizing system. The body member further comprises at least one fixed stabilizing surface positioned in an axially spaced relationship to the at least one moveable stabilizing member. The body member further comprises a gauge cutter positioned above the moveable stabilizing member and below the fixed stabilizing surface to expand the pilot hole to the final gauge.

Abstract: A material for applying hardfacings to the teeth of steel tooth rolling cutter drill bits comprises a mixture of refractory metal carbide, such as tungsten carbide, cobalt and metallic matrix powders formed into a core structure and surrounded by a thin metallic sheath. The metallic matrix powders include iron, deoxidizers and alloy powders. The ratio by weight of the metallic matrix powders to the sheath exceeds 2.5, so that the core structure provides most of the matrix material for the hardfacing and only a small proportion of such material is provided by the thin sheath, which may have a thickness of only 0.001" to 0.010". The core structure may include an organic binder, such as methylcellulose, to provide strength and to prevent segregation of the core materials.

Abstract: Drill bits having projecting inserts are completely coated with refractory material including on the edge margins about the inserts by thermally spraying with refractory particles whose particulate constituent under the spraying conditions is able to penetrate the inserts. Completely coated drill bits are provided.

Abstract: A device for drilling deep holes in the ground has at least two axial drill bits and an equal number of plates each having three shafts axially interconnecting the plates. Two of the shafts are rigidly attached to both plates and the third shaft is pivotably attached to both plates. The two rigid shafts are separable from the upper plate by pulling a locking pin separating a telescopic head of each shaft from the plate. At the separation, the shafts are telescopically shortened by springs and the drilling liquid is automatically shut off to the worn-out drill bit and opened to the new drill bit. The remaining third shaft eccentrically interconnects the plates, whereby the lower worn-out drill bit, at rotation, wears a semicircular evacuation pocket in the wall of the hole. The third shaft is successively pivoted outwards until it forms an angle of e.g. 80.degree. with the axis of the hole. An axle pin having rectangular cross-section retains the upper end of the third shaft via a sleeve with a slit.

Abstract: A rotary drill bit for drilling earth formations is disclosed having a plurality of cutting elements mounted on the head portion of the bit. The bit further includes a plurality of individual protrusions projecting from the head portion more than the extension of the cutting elements. The protrusions are fabricated of a metal more readily abraded by the earth formation than any of the cutting elements. The protrusions protect the cutting elements during handling of the bit and entry of the bit into a borehole; and, the protectors are abraded away to expose the cutting elements during drilling.

Abstract: The apparatus is a rocket with a drill head provided with a group of jet nozzles. One nozzle of this group is the face-forming one, while the plurality of the rows of the rest of the nozzles belong to imaginary circles concentric with the longitudinal axis of the rocket. The spacing of the nozzles in each row equals 4 to 7 critical diameters of the jet nozzle of the respective row, while the spacing of any pair of the adjacent rows of the nozzles in a projection of the drill head upon a plane perpendicular to the longitudinal axis of the rocket is 4 to 7 times greater than the mean diameter of the nozzles of the said pair of rows of nozzles.