Abstract: An assembly and method for protecting a pipe string movable within a wellbore. A generally annular body (56) is internally dimensioned to fit around said pipe string, and an outer sleeve (62) formed from at least two part-annular sections (58,60) and rotatably located over the annular body (56). A pair of substantially annular clamping means are adapted to restrict longitudinal movement of the body (56) and outer sleeve (62) relative to the pipe string, each clamping means comprising a one-piece clamping ring (70) and a fastener (74) adapted to tighten the clamping ring (70) around the pipe string. The body (56), outer sleeve (62), and clamping rings (70) may be formed from one or more sacrificial materials that can break up and be circulated out of the wellbore.

Abstract: A tubing shoe (10) for use on work strings in well bores as are typically utilised in oil and gas production. The shoe comprises a cylindrical body (12) upon which is arranged a reaming portion (22) including pairs of teardrop shaped raised reaming members (26), each pair being mounted oppositely, in parallel and longitudinally along the body. Adjacent pairs of members provide a funnel (42) for collecting approaching debris and a channel for grinding the debris. A nose (14) may be mounted on the end of the shoe, the nose being eccentric or including cutting blades to assist the shoe in breaking through shale and clay stone bridges. A non-aggressive stabiliser (54) in the form of helically arranged blades may also be located on shoe.

Abstract: This invention relates to a shoe for wellbore lining tubing and to a method of locating wellbore lining tubing in a wellbore. In one embodiment, a shoe (30) is disclosed which includes a tubular outer body (32) that is coupled to a wellbore lining tubing (28), and a tubular inner body (36) located within the outer body and coupled to fluid supply tubing (38). A generally annular flow area (44) is defined between the bodies which is in selective fluid communication with the well-bore (10), for the return flow of fluid from the wellbore through a flow port (62) in the outer body, along the shoe and into an annulus (46) defined between the wellbore lining tubing and the fluid supply tubing. A valve assembly (40) of the shoe has an actuating member (92) located within the inner body, and a flow controller (96) for selectively closing the flow port. A ball (98) is used to prevent further fluid flow through the inner body into the wellbore.

Abstract: Apparatus for use above and below a restriction in a well bore and a method of operation is described. The apparatus comprises an upper element, such as a wiper, operable in the well bore above the restriction and a lower element, which may be a lower wiper, operable in the well bore below the restriction. A drop ball sized to pass through the restriction is released from the upper element and thereby passes through the restriction to operate the lower element. In one embodiment, the apparatus is incorporated into a running tool, which may be used to hang liners by dimple forming.

Abstract: Apparatus, such as a liner, adapted to be hung in a downhole tubular such as casing is described. The apparatus includes one or more circumferentially distributed abrasive portions, arranged to be movable radially outwards by a dimple former or an expander. In an embodiment, the abrasive portions are provided on disks moveable in recesses in the outer diameter of the apparatus being hung. In an embodiment, the apparatus is hung by operating a dimple former provided on the running tool.

Abstract: A method is disclosed for running a completion string, such as casing, into a predrilled wellbore while allowing rotation of a downhole component with respect to the completion string. The downhole component may be a drill shoe or reamer shoe for example. There is also disclosed a drillable or millable drive assembly for driving the rotation of a portion of the casing assembly and other applications thereof.

Abstract: A swivel sub for connection in a work string between a workstring and a downhole apparatus is disclosed. The sub has a first substantially cylindrical body, including a sleeve portion having one or more teeth and a second substantially cylindrical body being partially located within the sleeve portion. The bodies are arranged to rotate relative to each other. A sliding sleeve, having one or more teeth arranged mutually engage with the first teeth is axially moveable between disengaged and engaged positions, in one embodiment by a pressure differential being created in the sub. Methods of running the tool are described, with particular application to setting and hanging of liners and screens. The invention also offers advantages for drilling applications.

Abstract: This invention relates to a shoe for wellbore lining tubing and to a method of locating wellbore lining tubing in a wellbore. In one embodiment, a shoe (30) is disclosed which includes a tubular outer body (32) that is coupled to a wellbore lining tubing (28), and a tubular inner body (36) located within the outer body and coupled to fluid supply tubing (38). A generally annular flow area (44) is defined between the bodies which is in selective fluid communication with the well-bore (10), for the return flow of fluid from the wellbore through a flow port (62) in the outer body, along the shoe and into an annulus (46) defined between the wellbore lining tubing and the fluid supply tubing. A valve assembly (40) of the shoe has an actuating member (92) located within the inner body, and a flow controller (96) for selectively closing the flow port. A ball (98) is used to prevent further fluid flow through the inner body into the wellbore.