Abstract: A vibratory milling machine has a vibratory housing confined to substantially linear reciprocating motion relative to a base, causing a tool carried by the housing to impact a mineral formation or other work piece substantially in a primary milling direction. The vibratory motion may be generated by two or more eccentrically-weighted rotors rotated by a common drive mechanism. The rotors may be arranged in pairs with the rotors of each pair rotating in opposite directions about parallel axes so that lateral oscillations cancel and longitudinal vibrations in the milling direction reinforce one another. In one embodiment, a hydrostatic fluid bearing is provided between the outer surface of each rotor and the housing.

Abstract: A vibratory milling machine has a vibratory housing confined to substantially linear reciprocating motion relative to a base, causing a tool carried by the housing to impact a mineral formation or other work piece substantially in a primary milling direction. The vibratory motion may be generated by two or more eccentrically-weighted rotors rotated by a common drive mechanism. The rotors may be arranged in pairs with the rotors of each pair rotating in opposite directions about parallel axes so that lateral oscillations cancel and longitudinal vibrations in the milling direction reinforce one another. In one embodiment, a hydrostatic fluid bearing is provided between the outer surface of each rotor and the housing.

Abstract: A vibratory milling machine has a vibratory housing confined to substantially linear reciprocating motion relative to a base, causing a tool carried by the housing to impact a mineral formation or other workpiece substantially in a primary milling direction. The vibratory motion may be generated by two or more eccentrically-weighted rotors rotated by a common drive mechanism. The rotors may be arranged in pairs with the rotors of each pair rotating in opposite directions about parallel axes so that lateral oscillations cancel and longitudinal vibrations in the milling direction reinforce one another. In one embodiment, a hydrostatic fluid bearing is provided between the outer surface of each rotor and the housing.

Abstract: A drill rod for a drill string has a thread at each end and is connected to an adjacent rod by a sleeve. The threads on the sleeve and rod are configured to reduce stress concentrations and provide sacrificial wear on the sleeve. The thread has a single start with a part circular root and the wear volume on the sleeve is less than that on the rod. The outer diameter of the rod is at least twice that of the inner bore.

Abstract: A hydraulic chuck for a drill string has a hydraulic actuator to operate the jaws. The actuator remains stationery while the spindle is rotated and a pair of skirts attached to the actuator cover the bearing assemblies. The jaws are supported in slots in the spindle and are part cylindrical to reduce stress in the spindle. The chuck is secured to a drive unit by bolts received in open slots in an attachment flange to facilitate attachment of the chuck after routine maintenance.

Abstract: A drilling tool, for example a core barrel inner tube assembly, includes a latch body mounting latches for movement into a latch seat to removably retain the assembly adjacent to a drill string bit end and to impart rotary movement to the latch body as the drill string is rotated. A spindle subassembly is connected to the axial inner end of the latch body, to in turn, mount a vibrational subassembly for imparting axial reciprocal movement to a core receiving tube as the drill string is rotated to facilitate entry of core into the tube. The vibrational assembly converts rotary motion of the spindle subassembly to axial reciprocal movement of the core receiving tube while the core receiving tube is not being rotated but is moved axially inwardly over the core.