Abstract: A downhole tool and a drill string (18?) comprising such a downhole tool is disclosed. The downhole tool comprises a housing having a first end and a second end, wherein a first fluid conduit (5) extends from an opening in the first end to an opening in the second end. A second (8?) and a third fluid conduit is further arranged in the housing, wherein the second (8) and third fluid conduits extend from an inner opening connected to the first fluid conduit (5) to an outer opening arranged in the outer side surface of the housing. The second and third fluid conduits (8, 24) are placed in acute angles relative to a longitudinal direction of the downhole tool. The second fluid conduit (8) is orientated so that it faces towards the first end. The third fluid conduit (24) is orientated so that it faces towards the first or second end. This provides an improved cleaning effect and transport effect without generating a Vortex around the outer opening of the second and third fluid conduits (8, 24).

Abstract: An activation method and a mechanism in which a pressure or flow sensor senses the pressure or flow rate of the treatment fluid being pumped through the drill string. A controller powered by a power source monitors the sensed pressure or flow rate within a first time window and via a suitable activator activates a first downhole tool or operation mode thereof if the sensed pressure or flow rate is stable with that time window. The controller monitors the sensed pressure or flow rate within a second time window and activates a second downhole tool or second operation mode of the first downhole tool if the sensed pressure or flow rate is stable with that time window. In one embodiment, the sensed pressure is combined with a rotation sensor sensing the rotation of the drill string. The controller logs the starting time for the pumping and the rotation.

Abstract: An agitator tool (1) for introducing forward and backward axial movement in a downhole tool of a drill string, where the agitator tool has a first axially moveable element (5) coupled to a second laterally moveable element (9) arranged inside a housing (2) via mechanical coupling. The mechanical coupling may be a pin and groove arrangement where the groove forms a modified or unmodified sinus shaped guiding loop that allows the first element (5) to oscillate within the housing (2). The second element (9) is driven by a turbine unit which may have flow regulating means. This provides an agitator tool comprising with very few moving and wearable parts. The shape of the groove sections allows an accelerated and/or de-accelerated forward and backward movement of the first element (5) that allows it to be used for various applications in a bore hole.

Abstract: An activation method and a mechanism in which a pressure or flow sensor senses the pressure or flow rate of the treatment fluid being pumped through the drill string. A controller powered by a power source monitors the sensed pressure or flow rate within a first time window and via a suitable activator activates a first downhole tool or operation mode thereof if the sensed pressure or flow rate is stable with that time window. The controller monitors the sensed pressure or flow rate within a second time window and activates a second downhole tool or second operation mode of the first downhole tool if the sensed pressure or flow rate is stable with that time window. In one embodiment, the sensed pressure is combined with a rotation sensor sensing the rotation of the drill string. The controller logs the starting time for the pumping and the rotation.

Abstract: An agitator tool (1) for introducing forward and backward axial movement in a downhole tool of a drill string, where the agitator tool has a first axially moveable element (5) coupled to a second laterally moveable element (9) arranged inside a housing (2) via mechanical coupling. The mechanical coupling may be a pin and groove arrangement where the groove forms a modified or unmodified sinus shaped guiding loop that allows the first element (5) to oscillate within the housing (2). The second element (9) is driven by a turbine unit which may have flow regulating means. This provides an agitator tool comprising with very few moving and wearable parts. The shape of the groove sections allows an accelerated and/or de-accelerated forward and backward movement of the first element (5) that allows it to be used for various applications in a bore hole.