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 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 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 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 casing centraliser (10) includes an annular body (12) and a substantially cylindrical bore (16) extending longitudinally through the body (12). A number of blades (14) extend longitudinally along the body (12) and are circumferentially distributed around the body (12) to define a flow path between each adjacent pair of blades (14). Each flow path provides a fluid flow path between longitudinally opposite ends of the centraliser (10) and each blade (14) has a radially outer edge providing a well bore contacting surface. The cylindrical bore (16) through the body (12) is a clearance fit around casing intended to be centralised by the centraliser (10). The centraliser (10) is typically manufactured from a material which includes zinc and is preferably a zinc alloy.

Abstract: A casing centraliser (10) includes an annular body (12) and a substantially cylindrical bore (16) extending longitudinally through the body (12). A number of blades (14) extend longitudinally along the body (12) and are circumferentially distributed around the body (12) to define a flow path between each adjacent pair of blades (14). Each flow path provides a fluid flow path between longitudinally opposite ends of the centraliser (10) and each blade (14) has a radially outer edge providing a well bore contacting surface. The cylindrical bore (16) through the body (12) is a clearance fit around casing intended to be centralised by the centraliser (10). The centraliser (10) is typically manufactured from a material which includes zinc and is preferably a zinc alloy.