Abstract: A downhole sealing apparatus for location in a downhole tubular includes a ball and a downhole seat. The ball may comprise a rigid core and a deformable covering. The ball is translatable downhole towards the seat, the ball and the seat having an open first configuration and a sealing second configuration. In the open first configuration the ball and seat are spaced apart such that fluid may flow through the seat. In the sealing second configuration the ball and the seat are in sealing engagement and the ball is deformed to maintain the sealing engagement with the seat in response to a differential pressure acting in a first axial direction and in response to a differential pressure acting in an opposite second axial direction.

Abstract: A coupling connects an inner string to a lower end of a bore-lining tubing, such as a liner. The coupling includes a catcher and may be provided in combination with at least one member for translating through the inner string and landing in the catcher. The member may be an occluding member, such as a ball for occluding a flow passage through the coupling.

Abstract: A method of locating bore-lining tubing, such as a liner (120), in a drilled bore (106) comprises selecting a buoyant material, such as air (138), having a density lower than the density of an ambient fluid, such as well fluid (180, 182). The buoyant material (138) and an inner tubing (140) are located within the bore-lining tubing (120) with the inner tubing (140) extending from a distal end of the bore-lining tubing to a proximal end of the bore-lining tubing. The inner tubing (140) is sealed to the distal end of the bore-lining tubing (120) and to a portion of the bore-lining tubing (120) spaced from the distal end to define an inner annulus (152) between the inner tubing (140) and the bore-lining tubing (120). A volume of the buoyant material (138) is retained within the inner annulus (152). An assembly (168) comprising the inner tubing (140) and the bore-lining tubing (120) and containing the volume of buoyant material (138) is run into a drilled bore (106).

Abstract: A method of conditioning a well bore featuring an annulus (50) between a bore-lining tubing (20) and a surrounding bore wall (110) comprises pumping conditioning fluid through an inner tubing (10) located within the bore-lining tubing (20) and into a portion of the well bore containing the bore-lining tubing to affect the temperature of the portion of the well bore containing the bore-lining tubing. The annulus (50) between the bore-lining tubing (20) and the surrounding bore wall (110) is at least partially filled with settable material (54). The affected temperature of the portion of the well bore containing the bore-lining tubing influences the setting of the settable material. For example, heating the bore may accelerate setting of the material, while cooling the bore may retard setting of the material.

Abstract: A method of conditioning a well bore featuring an annulus (50) between a bore-lining tubing (20) and a surrounding bore wall (110) comprises pumping conditioning fluid through an inner tubing (10) located within the bore-lining tubing (20) and into a portion of the well bore containing the bore-lining tubing to affect the temperature of the portion of the well bore containing the bore-lining tubing. The annulus (50) between the bore-lining tubing (20) and the surrounding bore wall (110) is at least partially filled with settable material (54). The affected temperature of the portion of the well bore containing the bore-lining tubing influences the setting of the settable material. For example, heating the bore may accelerate setting of the material, while cooling the bore may retard setting of the material.

Abstract: A well construction method, and corresponding apparatus, in which a drilled bore (106) is lined with a plurality of successively smaller diameter sections of bore-lining tubing includes at least one casing (108, 110, 112) and at least one liner (120). The well construction method comprises: drilling a final section of a bore (106) to intersect a hydrocarbon-bearing formation (130); providing a shoe (134) at a distal end of a liner and a running tool (150) at a proximal end of the liner, and coupling an inner string (140) between the shoe (134) and the miming tool (150); running the liner (120) into the final section of the bore (106) such that the liner extends into the hydrocarbon-bearing formation (130); pumping a settable material (116) from surface (104), through the inner string (140), and through the shoe (134) to at least partially fill an outer annulus (114) surrounding the liner (120); and retrieving the inner string (140) and the running tool (150).

Abstract: Downhole apparatus comprises: a tubular body for mounting on an inner tubing string (10); a first flow port (24); a second flow port (12a); and a connector (68) associated with the tubular body (10) and operable to at least one of engage with and disengage from a lower end (22) of a bore-lining tubing string (20). The apparatus has a first configuration in which the first flow port (24) is open and the second flow port (12a) is closed, whereby a settable material (54) may be pumped in a first direction (56) downwards through the tubular body, through the connector, and through the first flow port, and a second configuration in which the first flow port (24) is closed and the second flow port (12a) is open, whereby a fluid may be pumped in the first direction (58) downwards through the tubular body (10), exit the tubular body through the second flow port (12a), and then flow in a second direction upwards and externally of the tubular body.

Abstract: A method of conditioning a well bore featuring an annulus (50) between a bore-lining tubing (20) and a surrounding bore wall (110) comprises pumping conditioning fluid through an inner tubing (10) located within the bore-lining tubing (20) and into a portion of the well bore containing the bore-lining tubing to affect the temperature of the portion of the well bore containing the bore-lining tubing. The annulus (50) between the bore-lining tubing (20) and the surrounding bore wall (110) is at least partially filled with settable material (54). The affected temperature of the portion of the well bore containing the bore-lining tubing influences the setting of the settable material. For example, heating the bore may accelerate setting of the material, while cooling the bore may retard setting of the material.

Abstract: Downhole apparatus comprises: a tubular body for mounting on an inner tubing string (10); a first flow port (24); a second flow port (12a); and a connector (68) associated with the tubular body (10) and operable to at least one of engage with and disengage from a lower end (22) of a bore-lining tubing string (20). The apparatus has a first configuration in which the first flow port (24) is open and the second flow port (12a) is closed, whereby a settable material (54) may be pumped in a first direction (56) downwards through the tubular body, through the connector, and through the first flow port, and a second configuration in which the first flow port (24) is closed and the second flow port (12a) is open, whereby a fluid may be pumped in the first direction (58) downwards through the tubular body (10), exit the tubular body through the second flow port (12a), and then flow in a second direction upwards and externally of the tubular body.

Abstract: A downhole deployment system comprises a spoolable tubular member (76) adapted to be coupled to a subsea assembly and to extend to surface level. The deployment system also comprises a spoolable support member (96) adapted to extend through the spoolable tubular member (76) and into a wellbore. The spoolable tubular member (76) may define a conduit between the subsea assembly and the surface and the spoolable support member (96) may be utilised to extend through this defined conduit and into a wellbore, for example to deploy a tool into a wellbore, to engage a downhole tool or other object, for example for activation, retrieval or the like.