Abstract: A downhole actuator typically for a downhole tool such as a valve, and typically for incorporation in a string of tubulars in an oil or gas well has a central axis with radially movable counterweights on opposite sides of the axis, which move radially outward to change the activation state of the actuator. The counterweights are supported by link arms which control the movement of the counterweights in response to centrifugal force created by rotation of the body, for example, during rotary drilling operations of the string. Radial outward movement of the counterweights typically transmits axial forces between sleeves at the upper and lower ends of the counterweights, so when the counterweights move radially outward, the upper and lower sleeves approach one another, which typically triggers the actuator.

Abstract: A drillable debris barrier tool is positioned under a stage tool to protect tools therebelow from contamination with debris from the stage tool, as it is drilled out. The debris barrier tool includes features that facilitate drill up of stage tool debris and reduce the size of debris generated from removal of the barrier tool.

Abstract: A boring apparatus is described which comprises a substantially hollow vessel with a fixed base and a rotatable base. The rotatable base is provided, at its circumference, with at least one side cutter which rotatable with the rotatable base from a first position, in which the at least one side cutter serves to cover a respective opening provided in the vessel wall, to a second position, in which the opening in the vessel wall is exposed.

Abstract: A method and apparatus is provided for planting tree seedlings or the like. The apparatus includes an elongate tube, and a pair of blades pivotally mounted to the lower end of the tube. The blades are each pivotal between a closed position closing the lower end of the tube, and an open position wherein the lower end of the tube is open. In use, the lower end of the tube is rotatably advanced into the soil, with the rotating blades acting to pulverize the surrounding soil. Also, the blades will be pivoted to the closed position by the resistance of the soil, to prevent the soil from entering the tube. A seedling is then deposited downwardly through the tube, and the tube is rotated in the reverse direction to withdraw the tube from the soil. During reverse rotation, the blades pivot to their open position to permit the tube to lift from the seedling, and act to press and compact the soil about the roots of the seedling.

Abstract: A method and apparatus for removing bottom material from beneath the surface of a body of water includes a floatable base upon which a tower is mounted for extending vertically upwardly therefrom. A rigid, elongate member having a bucket is connected to the tower and shiftable relative thereto by means of a power-driven motor mounted adjacent the tower. The motor is operable for selectively shifting the elongate member in a substantially vertical direction to effect raising and lowering of the bucket. A carriage is connected by cables to the motor and is operable for substantially vertical shifting along guides provided on the tower. The elongate member is connected to the carriage and suspended therefrom and is also pivotally connected to the carriage to permit pivotal movement of the elongate member about a horizontal axis extending generally perpendicularly to the longitudinal axis of the elongate member.

Abstract: An underreamer includes a housing and a plurality of underreamer doors, each including a toggle mechanism for selectively extending and retracting the doors. Upon activation of the toggle mechanism thereby extending the doors, the doors are pivoted outwardly from the housing and the tops of the doors are simultaneously moved downwardly. In this manner the overall vertical height of an underreamer adapted to form a given diameter excavation may be substantially reduced.

Abstract: A drilling grab for pile foundations and well boreholes wherein the drilling grab comprises a grab body supporting circular grab spades which tilt from an open position to a closed position about pivot pins carried by the grab body. A radially projecting abutment interchangeably connected to the outer periphery of the grab body is engageable with the back of the grab spades when the same are in an open position. The abutment overlaps the periphery of the grab body and is characterized in that they consist of extension members adapted to grab spades of different sizes. The members are supported on radially projecting ribs located on the grab body.