Abstract: Apparatus for controlling a downhole device in a well, comprises a body having a control slot engaging a pin. Movement of the pin relative to the control slot switches the device between active and inactive states. The slot has at least one loop and at least one elongated axial track spaced around the body with respect to the at least one loop. The pin can move in the at least one elongated axial track between different configurations of the pin and slot which correspond to active and inactive configurations of the downhole device. Each of the at least one elongated axial track is connected to one of the at least one loop via a deviate branch track, and the control slot has no separate, dedicate return path for returning the pin from the deviate branch track to the elongated axial track.

Abstract: Apparatus for controlling a downhole device in a well has a body with a control slot and pin movable in the slot. The slot has a first inactive loop in which the pin can cycle between different idling configurations, and a second active loop in which the pin can move between different configurations which correspond to active and inactive configurations of the downhole device. The pin can be switched between the first and second loops, and can cycle between the different configurations within without switching between the different loops. The slot can be provided on a piston, and the axial movement of the piston in the bore can drive the relative movement of the pin and the slot.

Abstract: A drill string tubular component for use in an oil or gas well, in the form of a tubular having a central bore and a mechanism for mobilizing drill cuttings comprising at least one radial impeller (30) configured to apply radial thrust cuttings passing it, the radial impeller being located between first and second axial impellers (10, 20) configured to apply axial thrust to the fluids in opposite directions. Typically helical components of the first and second axial impellers extend in respective opposite directions, typically toward the radial impeller. Fluids are thus diverted radially away from the outer surface of the tubular component, and thereby enter a more turbulent region of the annulus, there reducing the tendency of the drill cuttings to settle out of suspension.

Abstract: Apparatus for controlling a downhole device in a well, comprises a body having a control slot engaging a pin. Movement of the pin relative to the control slot switches the device between active and inactive states. The slot has at least one loop and at least one elongated axial track spaced around the body with respect to the at least one loop. The pin can move in the at least one elongated axial track between different configurations of the pin and slot which correspond to active and inactive configurations of the downhole device. Each of the at least one elongated axial track is connected to one of the at least one loop via a deviate branch track, and the control slot has no separate, dedicate return path for returning the pin from the deviate branch track to the elongated axial track.

Abstract: An underreamer tool for use in a wellbore of an oil or gas well and a method of actuation. In an embodiment, the underreamer tool has body having a longitudinal axis and a fluid conduit, a tool element and an actuation device configured to urge the tool element relative to the body from a first configuration into a second configuration. In this embodiment, a portion of the tool has a curved actuation surface and as the tool element is urged across the curved actuation surface, the tool element is moved radially with respect to the body of the tool. Typically, the actuation device may include a piston driven by pressure of fluid circulated through the fluid flow conduit.

Abstract: Apparatus for controlling a downhole device in a well has a body with a control slot and pin movable in the slot. The slot has a first inactive loop in which the pin can cycle between different idling configurations, and a second active loop in which the pin can move between different configurations which correspond to active and inactive configurations of the downhole device. The pin can be switched between the first and second loops, and can cycle between the different configurations within without switching between the different loops. The slot can be provided on a piston, and the axial movement of the piston in the bore can drive the relative movement of the pin and the slot.

Abstract: A drill string tubular component for use in an oil or gas well, in the form of a tubular having a central bore and a mechanism for mobilising drill cuttings comprising at least one radial impeller (30) configured to apply radial thrust cuttings passing it, the radial impeller being located between first and second axial impellers (10, 20) configured to apply axial thrust to the fluids in opposite directions. Typically helical components of the first and second axial impellers extend in respective opposite directions, typically toward the radial impeller. Fluids are thus diverted radially away from the outer surface of the tubular component, and thereby enter a more turbulent region of the annulus, there reducing the tendency of the drill cuttings to settle out of suspension.

Abstract: The present invention relates to downhole tools, and in particular an underreamer tool for use in a wellbore of an oil or gas well and a method of actuation. In an embodiment, the underreamer tool has body having a longitudinal axis and a fluid conduit, a tool element and an actuation device configured to urge the tool element relative to the body from a first configuration into a second configuration. In this embodiment, a portion of the tool has a curved actuation surface and as the tool element is urged across the curved actuation surface, the tool element is moved radially with respect to the body of the tool. Typically, the actuation device may include a piston driven by pressure of fluid circulated through the fluid flow conduit.