Abstract: A casing end tool has a bowl-like (or cup-like) body defined by a wall having an outer convex surface and an inner concave surface opposite of the outer convex surface. The bowl-like body has a center axis. The inner concave surface is non-axisymmetric with respect to the center axis, while the outer convex surface is axisymmetric with respect to the center axis. The non-axisymmetric configuration is provided in one implementation through the presence of a set of raised boss or land structures formed on the inner concave surface. In another implementation, the non-axisymmetric configuration is provided by channels formed in the inner concave surface.

Abstract: A casing end tool has a mandrel and a body that is defined by a wall having an outer surface and an inner surface opposite of the outer surface. The body is fabricated from crystalline tungsten powder and a binder material. The inner surface includes a set of raised bosses or land structures. The body includes a plurality of blades on the outer surface. Each blade has a plurality of cutters. Blade channels and cutter channels on the blades enhance fragmentation of the body during drill out of the casing end tool.

Abstract: A casing end tool has a bowl-like (or cup-like) body defined by a wall having an outer convex surface and an inner concave surface opposite of the outer convex surface. The bowl-like body has a center axis. The inner concave surface is non-axisymmetric with respect to the center axis, while the outer convex surface is axisymmetric with respect to the center axis. The non-axisymmetric configuration is provided in one implementation through the presence of a set of raised boss or land structures formed on the inner concave surface.

Abstract: An apparatus for controlling the flow of fluid into a borehole through a conduit has a decelerating means adapted to be positioned within the conduit. The fluid could typically comprise drilling mud and/or cement, and in some embodiments, some of the cement can exit through apertures in a shroud of the apparatus to cement the decelerating means inside the conduit.

Abstract: A centralizer having a body with an inner surface provided with a friction-reducing slider, typically located in an annular recess on the inner surface of the body of the slider, spaced from the ends of the body. The slider can be formed separately from a body of the centralizer and subsequently attached thereto on the inner surface so that it is adapted to bear between the outer surface of the tubing to be centralized and the inner surface of the centralizer. This reduces rotational torque transmitted between the centralizer and the tubing, and assists in maneuvering of the tubular string into the desired position in the well.

Abstract: A centraliser having a body with an inner surface provided with a friction-reducing slider, typically located in an annular recess on the inner surface of the body of the slider, spaced from the ends of the body. The slider can be formed separately from a body of the centraliser and subsequently attached thereto on the inner surface so that it is adapted to bear between the outer surface of the tubing to be centralised and the inner surface of the centraliser. This reduces rotational torque transmitted between the centraliser and the tubing, and assists in maneuvering of the tubular string into the desired position in the well.

Abstract: This invention relates to a slotted expandable centraliser. In preferred embodiments, the centraliser is adapted to be used in conjunction with slotted casing, and can expand with the casing when an expander cone is propelled through the casing.

Abstract: A centralizer for use in centralizing casing or other tubulars such as tubulars in an oil or gas well comprising an annular body with a bore extending through the body and one or more blades, the centralizer being adapted to fit around a tubular to be centralized, and comprising a tempered metal such as austemperized ductile iron (ADI).

Abstract: A centraliser primarily for use when casing an oil or gas well, the centraliser having low frictions coatings or sliders on the outer surface thereof.

Abstract: A tubing shoe (30) comprising: a body (32) for mounting on the end of a tubing string; and reaming members (36) extending longitudinally and helically around the body, the reaming members providing substantially complete circumferential coverage of the body whereby, in use, when the tubing shoe is advanced axially into a bore, the reaming members (36) provide reaming around the shoe circumference. A rotatable torque reducing sleeve or centraliser (38) may also be mounted on the body, rearwardly of the reaming members.

Abstract: A centraliser (1) has a substantially annular body (6), a substantially cylindrical bore extending longitudinally through the body (6), and at least one roller ball (29). The roller ball (29) is preferably secured to the centraliser (1) in a manner which enables the roller ball (29) to rotate in all directions with respect to the centraliser (1), and one roller ball (29) is secured within at least one aperture (9; 109) provided in the sidewall of the body (6). Preferably, an assembly (27, 28, 39; 127, 128, 139) is provided to house the rollerball (29) within the at least one aperture (9; 109), and the roller ball (29) may be arranged to project either outwardly or inwardly from the sidewall.

Abstract: A centraliser primarily for use when casing an oil or gas well, the centraliser having low frictions coatings (19) or sliders (129) on the outer surface thereof.

Abstract: A casing centraliser and assembly comprising a tubular and a centraliser, the centraliser comprising a plastics material.

Abstract: A tubing shoe (30) comprising: a body (32) for mounting on the end of a tubing string; and reaming members (36) extending longitudinally and helically around the body, the reaming members providing substantially complete circumferential coverage of the body whereby, in use, when the tubing shoe is advanced axially into a bore, the reaming members (36) provide reaming around the shoe circumference. A rotatable torque reducing sleeve or centraliser (38) may also be mounted on the body, rearwardly of the reaming members.

Abstract: A casing centralizer and assembly comprising a tubular and a centralizer, the centralizer comprising a plastics material.

Abstract: A centralizer for use in centralizing casing or other tubulars such as tubulars in an oil or gas well comprising an annular body with a bore extending through the body and one or more blades, the centralizer being adapted to fit around a tubular to be centralized, and comprising a tempered metal such as austemperized ductile iron (ADI).

Abstract: A gripping device (10) is described which has an inner member (14) and an outer member (12). The inner member has a split (20) which define a first end (6) and a second end (8). A selectively operable device (18) is also included to keep the first and second ends (6, 8) apart to permit the device (10) to be placed around an object (30) and to permit the first and second ends (6, 8) to move towards each other so that the inner member (14) grips the object (30). At least part of an outer face (26) of the inner member (14) interfits with at least a part of an inner face (22) of the outer member (12) in a manner such that when a load is applied to the outer member (12), the inner face (22) of the outer member (12) acts upon the inner member (14) to cause compression of the inner member (14) thereby increasing the grip of the inner member (14) on the object (30).