Abstract: A method and apparatus for driving a hollow pile into the ground. By using a hollow rod having a short auger fixedly secured to a leading end portion thereof, excavated earth and sand are lifted to and around the upper portion of the auger where compressed air is spouted from nozzle orifices formed in the hollow rod thereby lifting the excavated earth and sand through the hollow pile and consequently discharging the same from the hollow pile. As earth and sand are discharged from the hollow pile, the pile is sunk or driven into the ground.

Abstract: A blast furnace taphole drill has a flaring head (3) with cutting edges (5) at its cutting end formed by intersecting angled faces. A central bore (4) carries cleaning air to the cutting end. To prevent blockage of the cleaning air bore (4) by debris and possible jamming of the drill, the head has deep radial grooves (6) formed at the bottoms of the valley shapes between the cutting edges (5). The grooves (6) extend radially from the air bore (4) and conduct the air so that it can get behind or under jammed debris. Reduced taphole drilling times can be achieved.

Abstract: A rock drill for percussion drilling comprising a central button insert and a row of outer button inserts. The central button insert extends beyond the outer inserts. For purposes of increasing the drilling rate and the life of the rock drill the ratios of respectively this extent (X) to the diameter (D) of the hole; X:D, and the transverse distance (Y) between the central insert and one of the outer inserts and the diameter (D); Y:D, shall be within predetermined limits.

Abstract: A rock-breaking implement, preferably for a self-propelled percussive machine for driving boreholes, having a body, at least a part of the body facing the borehole faces being cylindrical in shape. The body is provided with rock-breaking wedges which are arranged in such a manner that their blades extend radially at the end face of the body. The body has grooves opening outside to the periphery of the body and designed to remove broken rock, the grooves extending along helical lines and intersecting one another so that portions of the body located between the intersecting grooves define the rock-breaking wedges. Edges of said wedges which extend on the periphery of the body within the cylindrical part thereof define a continuous circle when projected to the plane of transverse section of the body and are designed for forming the walls of the borehole.

Abstract: A percussive tool, particularly a chisel for percussive working in rock, has a body portion, and a nozzle arrangement in the body portion, which is operative for forming a high-speed flow of a high-pressure fluid, particularly liquid, and directing the same to a working region of the body portion. The nozzle arrangement may include a plurality of nozzle holes which are open into the working region. It may also include at least one nozzle hole and at least one nozzle directing the flow of fluid into the nozzle hole. The nozzle may be supported by a supporting member which has an inner passage and extends from an inner chamber of a head section of the body portion into a receiving recess of a shaft section of the latter. The supporting member may be adjustable in the direction of a longitudinal axis of the chisel.

Abstract: An exhaust channel in a rock drilling head of a rotary impact drill has an pening which extends over the front face of the drill shaft and over the adjoining peripheral surface of the drill shaft. Clogging of the exhaust channel is prevented by providing clearances between the forward and peripheral surfaces of the drilling head and the bored hole which are too small to permit the passage of rock particles large enough to block the exhaust channel.

Abstract: A cutting tool for a pneumatic hammer operative at the bottom of a hole comprising a head for supporting cutting bits and a tail of reduced diameter extending from the head and provided with grooves forming alternating asymmetrical teeth engageable in symmetrical grooves provided in the interior of the front cylinder of the hammer. Each tooth of the cutting tool has a working flank in contact with the hammer during drilling which is of greater height than the other flank of the tooth so that each asymmetrical tooth can define in the symmetrical groove of the hammer an escape channel for compressed air from the hammer.

Abstract: A partially solid head bit having a flow passage therethrough located at approximately the center of the bit is shown. The bit is designed for use in conjunction with a hammer action drilling apparatus. The flow passage extends through a shank of the bit to the bottom thereof. Surrounding the shank is a substantially hemispherical spiraled burr having an opening therethrough. The burr pushes against a shoulder of the shank during drilling. The mating surfaces of the shank and burr are lubricated by a suitable oil reservoir. On spirals of the burr and on the lower end of the shank are mounted hardened inserts for impacting against and breaking up the formation through which the bit may drill. The bottom of the shank may be even with, extend through, or be recessed with respect to the lower edge of the burr. The shank is angled a few degrees off the centerline of the drilling string to cause a wobbling action upon rotating the drill bit.

Abstract: A mining bit, especially an impact bit for down-the-hole operations and the like, in which the bit comprises a body adapted for being chucked in an impact motor for being impacted by the hammer of the motor and for being rotated by the motor. The working end of the bit includes a detachable cup-shaped cap in which hard wear resistant inserts are mounted.

Abstract: An excavation tool, specifically, a down-the-hole bit which reduces a formation by being impacted axially against a formation while rotating and through which a supply of fluid, such as air, is supplied through a passage in the bit to the working face thereof to blow away the material taken by the bit and wherein the working face of the bit is provided with grooves extending outwardly from the lower end of the fluid supply passage to the periphery of the bit and in communication with axial grooves formed in the bit. The provision of the grooves in the working end of the bit in communication with the axial grooves in the outer periphery of the bit greatly improves the removal of debris which accumulates at the bottom of the hole being drilled and increases the efficiency of the bit.

Abstract: A well drilling bit of generally circular transverse cross-section and generally in the form of an elongated, generally cylindrical metal bit which tapers slightly outwardly toward its lower end with the lower end having a slight outward flare around the periphery thereof. A pair of diametrically opposed water courses in the form of longitudinal grooves extend from the lower end of the bit to a point adjacent the upper end thereof with the upper end of the bit having a screw threaded connection to the jar. The lower end of the bit is provided with a plurality of substantially parallel ridges and grooves in which the two center ridges are slightly higher than the others and the bottom end surface of the bit is slightly concave from edge to edge along the length of the ridges and valleys.

Abstract: Disclosed herein is a rotary-percussion earth boring bit that has an improved geometric configuration to extend cutting insert life and reduce cutting insert breakage. The bottom surface contains a flat transverse face with a bevelled edge. Two rows of circumferentially spaced cutting inserts protrude from the bevel. One of the rows is spaced inwardly from an outer row to define an inner row, which has inserts positioned between the circumferentially spaced inserts of the outer row. The longitudinal axes of these inserts are substantially perpendicular to the bevel and inclined outward at an acute angle to the axis of rotation of the bit. A generally longitudinally extending groove is formed between each two adjacent inserts of the outer row. This arrangement produces a symmetry that tends to minimize the number of reflective surfaces. This equalizes the stresses generated by the impact induced shock waves transmitted through the bit.