Abstract: A method of providing a downhole seal, such as a packer, in a drilled bore between inner tubing and outer tubing comprises: providing an intermediate tubing section defining a seal arrangement for engaging with the inner tubing; and radially plastically deforming the intermediate tubing section downhole to form an annular extension. The extension creates a sealing contact with the outer tubing.

Abstract: A tubing coupling method is provided. In one aspect, the method comprises providing a length of expandable tubing and a length of larger diameter non-expanding tubing, connecting an end portion of the expandable tubing to an end portion of the non-expanding tubing, running the tubing into a bore, and expanding the expandable tubing. The expandable tubing may form part of an expandable well or sand screen, or may be an expandable bore liner.

Abstract: A method of installing a liner in a drilled bore below a question of bore previously lined with casing comprises the steps of: running a length of liner into the bore such that at least an upper end of the liner in positioned in overlapping relation with at least a lower end of the casing; and plastically deforming a portion of the liner such that an external face of the portion forms an interference fit with an internal face of a portion of the casing. The interference fit preferably provides both hanging support for the liner and a fluid-tight seal between the liner and casing.

Abstract: A method of isolating a section of downhole tubing comprises: running a length of expandable tubing (20) into a tubing-lined borehole (12, 14) and positioning the expandable tubing (20) across a section of tubing to be isolated; deforming at least portions of the expandable tubing (32, 40) to increase the diameter of the portions to sealingly engage the tubing (14) and to isolate the tubing section.

Abstract: There is provided a downhole tubing sealing system (10) comprising a radially expandable slotted tubular body (16) carrying deformable material (22) on the exterior thereof; and a seal member (26) for location within the tubular body and for engaging an inner surface of said body. There is further provided a method of sealing a portion of a downhole bore, the method comprising locating a radially expandable slotted tubular body (16) carrying deformable material (22) on the exterior thereof in a bore, expanding the body radially into contact with the bore wall, and locating a seal member (26) within the body and radially extending the seal member to engage an inner surface of the body, so sealing portion of the downhole bore.

Abstract: A tubing coupling method comprises the steps: providing a length of expandable tubing (72) and a length of larger diameter non-expanding tubing (74); connecting an end portion of the expandable tubing (72) to an end portion of the non-expanding tubing (74) with a portion of expandable tubing (76); running the tubing (72, 74, 76) into a bore; and expanding the expandable tubing (72, 76). The expandable tubing (72) may form part of an expandable well or sand screen, or may be expandable bore liner (12).

Abstract: A method of forming a profile (10) in a section of tubing (12) comprises: providing an expander device (14) having at least one radially extendable expander member (22); positioning the device (14) at a predetermined location in the tubing (12); and extending the member (22) to deform the tubing (12) to create a profile (10).

Abstract: A method of forming a profile (10) in a section of tubing (12) comprises; providing an expander device (14) having at least one radially extendable expander member (22), positioning the device (14) at a predetermined location in the tubing (12); and extending the member (22) to deform the tubing (12) to create a profile (10).

Abstract: A downhole apparatus comprises a plurality of tubing sections. Each tubing section has substantially cylindrical portions initially of a first diameter for coupling to end portions of adjacent tubing sections. The end portions are expandable to a larger second diameter. Each tubing section also has an intermediate folded wall portions initially in a folded configuration. The intermediate folded wall portions are unfoldable to define a substantially cylindrical form of a third diameter.

Abstract: A method of providing a downhole seal, such as a packer (12), in a drilled bore between inner tubing (11) and outer tubing (16) comprises: providing an intermediate tubing section (18) defining a seal arrangement for engaging with the inner tubing; and radially plastically deforming the intermediate tubing section downhole to form an annular extension (40a, 40b). The extension creates a sealing contact with the outer tubing (16).

Abstract: A method of providing a downhole seal, such as a packer (12), in a drilled bore between inner tubing (11) and outer tubing (16) comprises: providing an intermediate tubing section (18) defining a seal arrangement for engaging with the inner tubing; and radially plastically deforming the intermediate tubing section downhole to form an annular extension (40a, 40b). The extension creates a sealing contact with the outer tubing (16).

Abstract: Apparatus (10) for facilitating coupling and cementing of downhole tubulars (12, 28) comprises a tubing section (12, 10) for use in lining a bore. The tubing section has upper and lower ends and defines a tubing wall having cement outlets (20) spaced from the lower end of the tubing. The lower end of the tubing is selectively closed, and swab cups (22) are provided externally of the lower end of the tubing below the cement outlets (20) for restricting passage of cement.

Abstract: A tubing connector for joining the ends of two lengths of expandable tubing including two expandable tubular portions for mounting on the ends of the lengths of expandable tubing. Each portion includes a plurality of circumferentially spaced couplings for engaging corresponding couplings on the other portion. The engaging parts of the couplings are located on parts of the tubular portions which define an upset following expansion.

Abstract: Expandable tubing, as utilized in downhole applications in the oil and gas exploration and extraction industries, includes tubing having a wall with a multiplicity of overlapping longitudinally extending slots therein. The slots have end portions and at least some of the slots are wider at at least one end portion.

Abstract: Downhole apparatus is disclosed for use in expanding liner or tubing. The apparatus comprises a body for connection to a string and an expansion portion on the body. The expansion portion includes a plurality of radially movable parts for defining an outer surface thereof. The parts are initially arranged in an axially and circumferentially offset first configuration in which the parts may assume a smaller diameter first configuration. The apparatus is then run Into a borehole and through a length of expandable tubing. The parts are the moved radially outwardly and axially aligned such that the parts assume a larger diameter second configuration and define a substantially continuous outer circumference. The expansion portion is then pulled through the tubing to expand the tubing.