Abstract: A flow restrictor for restricting flow in an annulus, the flow restrictor comprising a body and a restrictor assembly mounted on the body, wherein the restrictor assembly is actuatable between a run-in configuration and a set configuration in which at least a portion of the restrictor assembly is radially splayed to thereby substantially restrict flow in the annulus, and wherein the flow restrictor is actuatable by fluid flow over the restrictor assembly above a threshold flow rate to actuate the restrictor assembly from the run-in configuration to the set configuration.

Abstract: A downhole slip apparatus that includes a radially extendable slip assembly. The radially extendable slip assembly including a primary slip arrangement and a secondary slip arrangement. The downhole slip apparatus is arranged such that during a first phase of operation the primary and secondary slip arrangements are radially extendable simultaneously from a retracted configuration towards and/or into a first extended configuration. The downhole slip apparatus is also arranged such that during a subsequent second phase of operation the secondary slip arrangement is radially extendable relative to the primary slip arrangement towards and/or into a second extended configuration.

Abstract: A downhole actuator (30) comprises a tubular housing (34) which includes an indexing profile (42) on an inner surface thereof, and an indexing sleeve (46) mounted within the housing (34). The indexing sleeve (46) comprises an engaging arrangement including first and second axially spaced engagement members (52, 54) which cooperate with the indexing profile (42) of the housing (34) to be sequentially engaged by an actuation object (48) passing through a central bore (50) of the indexing sleeve (46) to drive the indexing sleeve (46) one discrete step of movement through the housing (34) towards an actuation site.

Abstract: A downhole tool (32) comprises a tool housing (34) defining a central bore (35) and including a fluid port (20), and a valve member (40) mounted within the housing (34) and being movable from a closed position in which the fluid port (20) is blocked to an open position in which the fluid port (20) is opened. The tool (32) further comprises a catching arrangement (41) mounted within the housing (34) and comprising one or more radially movable seat members (106), and being configurable from a free configuration in which the seat members (106) permit an object (48) to pass through the tool (32), to a catching configuration in which the seat members (106) catch an object (48) passing through the tool (32).

Abstract: A downhole tool (32) comprises a tool housing (34) defining a central bore (35) and including a fluid port (20), and a valve member (40) mounted within the housing (34) and being moveable from a closed position in which the fluid port (20) is blocked to an open position in which the fluid port (20) is opened. The tool (32) further comprises a catching arrangement (41) mounted within the housing (34) and comprising one or more radially moveable seat members (106), and being configurable from a free configuration in which the seat members (106) permit an object (48) to pass through the tool (32), to a catching configuration in which the seat members (106) catch an object (48) passing through the tool (32).

Abstract: A downhole actuator (30) comprises a tubular housing (34) which includes an indexing profile (42) on an inner surface thereof, and an indexing sleeve (46) mounted within the housing (34). The indexing sleeve (46) comprises an engaging arrangement including first and second axially spaced engagement members (52, 54) which cooperate with the indexing profile (42) of the housing (34) to be sequentially engaged by an actuation object (48) passing through a central bore (50) of the indexing sleeve (46) to drive the indexing sleeve (46) one discrete step of movement through the housing (34) towards an actuation site.

Abstract: A downhole tool (32) comprises a tool housing (34) defining a central bore (35) and including a fluid port (20), and a valve member (40) mounted within the housing (34) and being moveable from a closed position in which the fluid port (20) is blocked to an open position in which the fluid port (20) is opened. The tool (32) further comprises a catching arrangement (41) mounted within the housing (34) and comprising one or more radially moveable seat members (106), and being configurable from a free configuration in which the seat members (106) permit an object (48) to pass through the tool (32), to a catching configuration in which the seat members (106) catch an object (48) passing through the tool (32).

Abstract: A downhole slip apparatus that includes a radially extendable slip assembly. The radially extendable slip assembly including a primary slip arrangement and a secondary slip arrangement. The downhole slip apparatus is arranged such that during a first phase of operation the primary and secondary slip arrangements are radially extendable simultaneously from a retracted configuration towards and/or into a first extended configuration. The downhole slip apparatus is also arranged such that during a subsequent second phase of operation the secondary slip arrangement is radially extendable relative to the primary slip arrangement towards and/or into a second extended configuration.

Abstract: A packing element comprising a tube having a longitudinal length. The tube includes a first end and a second end opposing the first end, an external portion including a plurality of circumferential ribs, and an internal portion opposing the external portion. The internal portion of the tube includes i) a central portion extending along a portion of the longitudinal length of the tube between the first end and second end of the tube, wherein the central portion includes a relief, ii) a first tapered portion radially tapering along the longitudinal length from the central portion towards the first end, and iii) a second tapered portion tapering along the longitudinal length from the central portion towards the second end.

Abstract: A seal stack including a sealing element including an annular seal ring having a diameter and an axis defined therethrough perpendicular to the diameter, a groove defined in the seal ring, wherein the groove has an opening at a first end of the seal ring, and a swellable energizer disposed in the groove, wherein the swellable energizer swells upon exposure to a solvent causing the seal ring to expand. The seal stack also includes a first annular back-up and a second annular back-up provided at opposing ends of the sealing element, wherein said first back-up includes an interior surface that receives a second end of the sealing element.

Abstract: A flow restrictor for restricting flow in an annulus, the flow restrictor comprising a body and a restrictor assembly mounted on the body, wherein the restrictor assembly is actuatable between a run-in configuration and a set configuration in which at least a portion of the restrictor assembly is radially splayed to thereby substantially restrict flow in the annulus, and wherein the flow restrictor is actuatable by fluid flow over the restrictor assembly above a threshold flow rate to actuate the restrictor assembly from the run-in configuration to the set configuration.

Abstract: A downhole tool (32) comprises a tool housing (34) defining a central bore (35) and including a fluid port (20), and a valve member (40) mounted within the housing (34) and being moveable from a closed position in which the fluid port (20) is blocked to an open position in which the fluid port (20) is opened. The tool (32) further comprises a catching arrangement (41) mounted within the housing (34) and comprising one or more radially moveable seat members (106), and being configurable from a free configuration in which the seat members (106) permit an object (48) to pass through the tool (32), to a catching configuration in which the seat members (106) catch an object (48) passing through the tool (32).

Abstract: A downhole actuator (30) comprises a tubular housing (34) which includes an indexing profile (42) on an inner surface thereof, and an indexing sleeve (46) mounted within the housing (34). The indexing sleeve (46) comprises an engaging arrangement including first and second axially spaced engagement members (52, 54) which cooperate with the indexing profile (42) of the housing (34) to be sequentially engaged by an actuation object (48) passing through a central bore (50) of the indexing sleeve (46) to drive the indexing sleeve (46) one discrete step of movement through the housing (34) towards an actuation site.

Abstract: A downhole actuator (30) comprises a tubular housing (34) which includes an indexing profile (42) on an inner surface thereof, and an indexing sleeve (46) mounted within the housing (34). The indexing sleeve (46) comprises an engaging arrangement including first and second axially spaced engagement members (52, 54) which cooperate with the indexing profile (42) of the housing (34) to be sequentially engaged by an actuation object (48) passing through a central bore (50) of the indexing sleeve (46) to drive the indexing sleeve (46) one discrete step of movement through the housing (34) towards an actuation site.

Abstract: A downhole tool (32) comprises a tool housing (34) defining a central bore (35) and including a fluid port (20), and a valve member (40) mounted within the housing (34) and being moveable from a closed position in which the fluid port (20) is blocked to an open position in which the fluid port (20) is opened. The tool (32) further comprises a catching arrangement (41) mounted within the housing (34) and comprising one or more radially moveable seat members (106), and being configurable from a free configuration in which the seat members (106) permit an object (48) to pass through the tool (32), to a catching configuration in which the seat members (106) catch an object (48) passing through the tool (32).

Abstract: A seal stack including a sealing element including an annular seal ring having a diameter and an axis defined therethrough perpendicular to the diameter, a groove defined in the seal ring, wherein the groove has an opening at a first end of the seal ring, and a swellable energizer disposed in the groove, wherein the swellable energizer swells upon exposure to a solvent causing the seal ring to expand. The seal stack also includes a first annular back-up and a second annular back-up provided at opposing ends of the sealing element, wherein said first back-up includes an interior surface that receives a second end of the sealing element.

Abstract: Apparatus for aspirating and dispensing liquid samples in an analytical instrument, e.g., a hematology instrument, includes a liquid-sampling valve that, while operating to segment and position for dispensing one or more precise volumes of a liquid sample that has been aspirated into the valve by a pump, simultaneously enables the apparatus to be operated in an aspirate/dispense (suck-and-spit) mode in which a liquid sample can be selectively driven through the valve in opposite directions by a pump, e.g., a syringe pump.

Abstract: Apparatus for aspirating and dispensing liquid samples in an analytical instrument, e.g., a hematology instrument, includes a liquid-sampling valve that, while operating to segment and position for dispensing one or more precise volumes of a liquid sample that has been aspirated into the valve by a pump, simultaneously enables the apparatus to be operated in an aspirate/dispense (suck-and-spit) mode in which a liquid sample can be selectively driven through the valve in opposite directions by a pump, e.g., a syringe pump.

Abstract: A method for discriminating and quantifying platelets within an analyzed blood sample involves initially diluting the blood sample with a ghosting reagent that causes a change in the index of refraction of the red blood cells. Owing to the change in the index of refraction, light scattered from the ghosted red blood cells will be substantially reduced relative to light scattered from platelets. This results in locations of platelets within a scatterplot of the analyzed blood sample to fall within a region distinguishable from those containing normal red blood cells, fragmented red blood cells, and microcytic red blood cells.

Abstract: Apparatus and method for aspirating liquid from a container, e.g., a test tube or other vessel, includes apparatus for sensing that an aspiration probe tip is contacting the inside bottom wall of the container, whereby a maximum volume of liquid can be aspirated from the container. According to the invention, an encoder is mounted on the driven member of a motor (e.g., on a rotatably-driven drive shaft or a nut of a stepper or D.C. motor, or on a linearly-driven shaft of a linear actuator) used to rectilinearly advance the probe tip into the container. Such encoder produces a series of pulses indicating the speed and/or linear position of the probe tip. A motor controller responds to a predetermined change in pattern of pulses from the encoder indicating that movement of the probe tip has been resisted by the vessel bottom, whereby further movement of the driven member and of the probe connected thereto is arrested, and the probe tip remains in contact with the vessel bottom.