Abstract: In rock drilling utilizing mechanical destruction of the rock and circulation of drilling fluid for removing debris from the cutting face, the drilling fluid is directed on to the cutting face in the form of two opposed pulsed jets, the cycles of which are 180.degree. out of phase. In order to achieve the phased opposition of the pulsed jets a ball is disposed in the distribution chamber of the drilling fluid and is subjected to a combination of hydraulic and mechanical forces which cause the ball to oscillate between two end positions in which the ball respectively closes off one of two outlet ducts leading to nozzles which direct the drilling fluid towards opposite points on the bottom of the drill hole.

Abstract: A hydromechanical drilling tool which combines a high pressure water jet drill with a conventional roller cone type of drilling bit. The high pressure jet serves as a tap drill for cutting a relatively small diameter hole in advance of the conventional bit. Auxiliary laterally projecting jets also serve to partially cut rock and to remove debris from in front of the bit teeth thereby reducing significantly the thrust loading for driving the bit.

Abstract: A drill bit is disclosed for drilling large diameter shafts. The drill bit comprises a main bit body having a plurality of rolling cutters rotatively mounted thereon. The cutters function to contact and disintegrate the earth formations at the bottom of the shaft thereby creating rock chips or cuttings. Water or drilling mud is pumped down the shaft and across the face of the main bit body for cooling the drill bit and for flushing the chips away from the shaft bottom. An auxiliary flow enhancer is attached beneath the main bit body for increasing the radial flow velocity of the drilling mud across the face of the bit body in order to remove the chips more efficaciously. The flow enhancer comprises a shaft mounted impeller such as a screw conveyor, a spiral brush, or a paddle-blade configuration. The shaft of each device is attached radially on the main bit body with each shaft having a drive wheel mounted thereon adjacent the bit body periphery.

Abstract: A rotary drill bit having a plurality of journal-mounted rotating cutters and jet passageways through which drilling fluid is discharged between the cutters is provided with removable nozzles for air or other drilling fluid. The nozzles are provided with a peripheral groove and secured in place in said passageways by the divided ends of a bifurcated retaining pin.

Abstract: A three cone rock bit comprises legs and freely rotating cutters mounted on the same. The angle .alpha. between the projections of the rotational axes of two adjacent cutters on a plane perpendicular to the axis of the bit is more than 120.degree. but less than 170.degree.. A flow nipple to supply drilling fluid is provided in the bit, the outlet thereof being positioned between said two cutters.

Abstract: Process and apparatus for the ultrasonic treatment of underground rocky strata, primarily for drilling therein, and for increasing the permeability of the strata. A flushing medium is made to flow through a mechanical drilling tool such as a rotary drill bit with rock-breaking elements, a pressure wave is superposed on the static pressure of the flowing medium at the location of rock breaking, and the frequency of the pressure wave in the ultrasonic range, preferably between 20 and 100 kHz; good results have been obtained at 27 kHz. The inventive apparatus includes a passageway in the tool for the flushing medium, a resonance chamber in the path of the medium, together with an exciting or interference element, constituting means for changing the flow conditions of at least part of the medium from laminar to turbulent, producing therein a pressure wave, and superposing the latter, as aforesaid. The resonance chamber preferably opens into a jet nozzle forming part of the drilling tool.

Abstract: The raise boring head comprises a stem in which is formed a passageway which extends fully throughout the axial length thereof for conducting fluid therethrough. The uppermost end of the passageway defines an inlet and, at the lowermost end, the same comprising an outlet, a coupling is fixed to receive threaded fitting elements for use to control and/or direct fluid flow from the outlet or axial end of the passageway. By this means a spray nozzle, as disclosed in one embodiment, can be threaded into the coupling to direct a conical spray of water onto the walls of the bore in order to suppress dust. In alternative embodiments, hose or like conduits can be used in operation with the passageway to facilitate the use of hydraulic, electrical, or pneumatic tools and devices in a subterranean chamber or tunnel below the raise.

Abstract: This earth boring drill apparatus has a cutter mounting leg extending from one side of a drive stem and a removable cutter assembly, including a fixed shaft and cutter journaled for rotation on the shaft supported between the drive stem and the mounting leg. The stem has a bore for slidably receiving the inner end of the shaft. The cutter mounting leg terminates in an end surface extending parallel to the axis of rotation of the bore and shaft. A shaft supporting lug projecting from the outer end of the shaft has a surface which is parallel to the end surface on the leg. The opposed surfaces respectively have a V-shaped projection and mating groove which provide lateral alignment and prevent shaft rotation while permitting the shaft to be movable in an axial direction by an amount sufficient to permit the shaft to be withdrawn from the bore.

Abstract: A raise drill having a central drive stem to which a surrounding cutter mounting frame is attached, the cutter mounting frame supporting a plurality of rotary cutter units. One or more inboard cutter units each include a shaft and a rotary cutter journaled for rotation on the shaft. One end of the shaft is inserted in a bore extending into the side of the stem. A yoke member receives the outer end of the shaft. The yoke member is supported by a mounting block secured to the frame. The mounting block has first and second intersecting planar surfaces, the first surface extending substantially parallel to the axis of the bore and the second surface extending in an obtuse angle to the first surface facing the stem. The yoke member has a first surface which slidably engages the first surface of the mounting member, and a second surface spaced from the second surface of the mounting member, allowing axial movement of the cutter shaft into and out of the bore.

Abstract: A drill bit for drilling deep wells such as oil wells has a cone at the bottom and a fluid bore at the top. The fluid is directed by nozzles upward through a passageway so that the cone is maintained free of fluid and the cuttings from the cone are picked up by suction and carried through the discharge passageway. The jet from the discharge passageway supports the column of fluid surrounding the drill stem.

Abstract: A nozzle is releasably locked in a drilling fluid passage of a rotary rock bit by a retainer member which bridges between matching grooves in the periphery of the nozzle and in the wall of the passage respectively. The retainer member is introduced to the matching grooves through a first passageway that extends from the surface of the bit to the matching grooves. The grooves lie in a common plane. A second passageway extends at an angle to the common plane from the surface of the bit to the matching grooves. A drive-out tool is inserted through the second passageway to remove the retainer member.

Abstract: A raise type of earth boring drill in which the cutter assembly is detachably secured to the drive stem to permit replacement of the stem. The stem slidably engages a central opening in the cutter assembly, the cutter assembly engaging a shoulder on the stem which carries axial loads in the drill. The cutter assembly is detachably anchored by a plurality of bolts to a torque plate attached to the end of the stem for transmitting torque load to the cutter assembly, the bolts clamping the cutter assembly against the shoulder.

Abstract: Apparatus is disclosed wherein a tubular body connectible in a drill string and having a float valve arranged therein to normally close the string, as the string is lowered into a well bore, is provided with a plurality of ports connecting its bore above the float valve with its exterior, and valve means for movement from a position normally closing to a position opening the ports when the exterior fluid pressure exceeds the fluid pressure in the bore above the float valve by a predetermined amount.

Abstract: Drill cuttings are effectively removed from the bottom of a bore before they can adversely affect the operation of the bit. The bit includes a body member rotatably supporting individual cutter members. A shield means projects from the body member proximate the cutter members. A first portion of the shield means has an outside diameter substantially equal to the outside diameter of the cutter means and substantially equal to the diameter of the bore and a second portion having an outside diameter substantially less than the outside diameter of the cutter members and substantially less than the diameter of the bore. A first passage extending through the bit is adapted to provide communication with a vacuum source to assist in removing the drill cuttings. A second passage extending along the length of the bit is adapted to provide communication with a gas pressure source to assist in removing the drill cuttings.