Abstract: A downhole cleaning tool (120) for use in a drilled bore, such as an oil and gas well (100). The tool (120) comprises a tubular body (130) defining an internal bore (136) and at least one radially extending blade (148) defining a pocket (152) having sides and a base. A cam-activated radially extendable cleaning element (154) is mounted in the pocket (152) and is movable between a retracted position and an extended position. Multiple pockets (152) and cleaning elements (154) may be provided. The activating cam may be in the form of a pipe, which may be a single unitary part or may be in multiple parts. The parts of the multiple-part pipe may be axially spaced and may activate the cleaning elements in a staggered or sequential manner.

Abstract: A drilling method comprising running a drill string (12) part way into a bore (11); then pumping fluid through the drill string; then running the drill string further into the bore; and then reconfiguring a check valve (20) located towards the distal end of the drill string from a running configuration, in which the valve permits flow both up and down the string, to a drilling configuration in which the valve permits flow down through the string but prevents flow up through the string.

Abstract: In a drill string for oil wells and the like a method and apparatus for delivering fluids to the drilled hole employs a bypass port above fluid outlets in the distal end of the string. The port may be used to deliver fluid such as lost circulation material (LCM) to the drilled hole from the surface. A volume of the fluid may be locked in the string between the port and the fluid outlets such that fluid is prevented from passing from the hole into the string via the fluid outlets.

Abstract: An activating device is provided for location in downhole tubing. The device defines an activation profile which is initially maintained at a larger diameter than a tubing seat, such that the device may land on and be held up by the seat. The profile may be subsequently re-configured to radially retract, allowing the device to pass through the seat.

Abstract: Apparatus (100) for use in top filling of tubulars comprising an inlet (200) for fluid communication with a top drive for providing top filling fluid, and an outlet (300) for fluid communication with a tubular. The apparatus (100) comprises a filter configuration (120), in fluid communication with the inlet (200) and the outlet (300) and configured to remove debris from a top filling fluid flow flowing from the inlet (200) to the outlet (300) during top filling of a tubular.

Abstract: A downhole bypass valve comprises a tubular body including a side port and a sleeve axially movably mounted in the body and normally biased to a closed position to close the side port. An activating device is configured to be pumped or dropped into the body to engage the sleeve and permit movement of the sleeve to an open position and open the side port. A latch has a part in the body and a part in the activating device, the parts of the latch configured to engage and retain the sleeve in the open position. The activating device is further operable to disengage from and translate through the sleeve and the parts of the latch are further operable to disengage and permit the sleeve to return to the closed position.

Abstract: A drilling method comprising running a drill string (12) part way into a bore (11); then pumping fluid through the drill string; then running the drill string further into the bore; and then reconfiguring a check valve (20) located towards the distal end of the drill string from a running configuration, in which the valve permits flow both up and down the string, to a drilling configuration in which the valve permits flow down through the string but prevents flow up through the string.

Abstract: An activating device is provided for location in downhole tubing. The device defines an activation profile which is initially maintained at a larger diameter than a tubing seat, such that the device may land on and be held up by the seat. The profile may be subsequently re-configured to radially retract, allowing the device to pass through the seat.

Abstract: A downhole bypass valve comprises a tubular body including a side port and a sleeve axially movably mounted in the body and normally biased to a closed position to close the side port. An activating device is configured to be pumped or dropped into the body to engage the sleeve and permit movement of the sleeve to an open position and open the side port. A latch has a part in the body and a part in the activating device, the parts of the latch configured to engage and retain the sleeve in the open position. The activating device is further operable to disengage from and translate through the sleeve and the parts of the latch are further operable to disengage and permit the sleeve to return to the closed position.

Abstract: A method of delivering material, typically lost circulation material (LCM), into a hole via a tubular string comprises: opening a bypass port in a tubular string located in a drilled hole, the bypass port being provided above fluid outlets in the distal end of the string; delivering material through the string from surface, the material passing through the bypass port and into the drilled hole; and locking a volume of fluid in the string between the bypass port and the fluid outlets such that fluid is prevented from passing from the hole into the string via the fluid outlets.

Abstract: There is provided an apparatus (100) for use in top filling of tubulars, the apparatus (100) comprising an inlet (200) for fluid communication with a top drive for providing top filling fluid, and an outlet (300) for fluid communication with a tubular, wherein the apparatus (100) comprises a filter configuration (120), in fluid communication with the inlet (200) and the outlet (300) and configured to remove debris from a top filling fluid flow flowing from the inlet (200) to the outlet (300) during top filling of a tubular.

Abstract: A method of checking for restrictions in a string of tubing formed of a plurality of tubing sections. The method involves providing a profile in the tubing string, providing a drift member adapted to engage with the profile, passing the drift member through the tubing string, and determining whether the drift member has engaged with the profile prior to separating the tubing sections.

Abstract: A downhole tool (10) comprises a body (12) defining a bore. The body includes a valve arrangement (18) including flow ports (24) in the wall of the body. The ports may be opened or closed. In addition, a variable flow restriction (30) is provided in the bore (14), the degree of restriction tending to decrease as flow across the restriction increases. The variable flow restriction may be utilised to actuate the valve arrangement.

Abstract: A method of checking for restrictions in a string of tubing formed of a plurality of tubing sections. The method involves providing a profile in the tubing string, providing a drift member adapted to engage with the profile, passing the drift member through the tubing string, and determining whether the drift member has engaged with the profile prior to separating the tubing sections.

Abstract: A fluid flow actuated downhole tool is configurable in at least a first tool configuration and a second tool configuration. The tool comprises a tubular housing and an activating sleeve, the housing being adapted to catch the sleeve when the sleeve is dropped from surface and the engagement of the sleeve with the housing permitting actuation of the tool between the first and second tool configurations. A flow restriction is provided for permitting fluid flow actuation of the tool when the activating sleeve has been caught in the body.