Abstract: A reinforcement ring, includes an annular coil spring with a core unit arranged inside to prevent deforming or twisting of the ring under load. The core unit is formed from a chain of interlinked elements, each having a male part and a female part; the male parts of each element being engaged with corresponding female parts of an adjoining element.

Abstract: Downhole plug, especially designed for closing an annular conduit in an oil or gas well, under high pressure and temperature. It has two radially expandable ring elements 13, 15, which are arranged on a carrying cylindrical element 32, between two mutually axially movable pressure elements 12, 14, having an expansion sleeve in between. The ring elements can, by insertion of the downhole plug in a well, be expanded from an inner position, seen radially, to a sealing position against the wall of the well. The radially expandable ring elements 13, 15, comprises a closed series of circumferentially overlapping seal elements 13A, 15 A. By the expanding movement they are mutually moved in the circumferential direction, thereby maintaining a seal against each other. They form an outer sealing surface 38, which can provide a seal against a cylindrical pipe wall, and they have an inwards facing sealing surface 47.

Abstract: A retrievable well plug has a through shaft (12) with link connections (62, 64) and a packer element (66). By pushing the link connections (62, 64) and the packer element towards each other, the link connections (62, 64) and the packer element (66) expand radially, such that a mechanical barrier for the packer element (66) is formed. The links (76; 174, 176) have a generally T-shaped cross sectional profile and include an arm (78) with an end (80) meant for fastening to the fastening devices (72, 74). The other end of the arm (78) fastens to the second link (77) of the link connection (62, 64). Upper supporting surfaces (84, 86; 184; 192, 194) of the links (76; 174, 176) form an approximately tight mechanical barrier against the packer element (66) in an expanded position. The anchoring device (20) has a number of gripping devices (22), wherein the gripping devices (22) at setting of the well plug (10) expand radially, thereby providing an anchoring of the well plug (10) to the well bore wall.

Abstract: A device for use with a retrievable bridge plug (30) comprising an upper packer element (3) and a lower packer element (11). The upper element (3) is connected to an upper link (6), which can rotate around a first pin (5). Upper link (6) is rotatably connected to a lower link (8) by a second pin (7). Lower link (8) can rotate around a third pin (9). An angle (&agr;) is formed between the longitudinal axis of the bridge plug and a line extending through the first pin (5) and the second pin (7), and correspondingly through the second pin (7) and the third pin (9), which is greater than zero when upper link (6) and lower link (8) is drawn. Upper link (6) and lower link (8) are arranged for, at setting, to expand radially by compression of upper packer bracket (3) against lower bracket (12), for forming a mechanical barrier for upper packer element (3) and lower packer element (11).

Abstract: A bridge plug (1) for use in a casing (7), for example in oil and/or gas wells, comprising a packing element (2) of a resilient material is disclosed. The packing element (2) is adapted for at impact from a running tool to expand from a first diameter, to a second diameter that is greater than the first diameter which corresponds to the inner diameter of the casing that is to be sealed. The packing element (2) is divided in zones forming at least one expandable sealing packing element (34, 35) and at least one expandable support packing element (31, 32, 33), where the support packing elements (31, 32, 33) are expandable to a smaller diameter than the sealing packing elements (34, 35). The bridge plug (1) is further comprised of an anchoring means (3) that is provided for holding the bridge plug (1) in its place in the casing by a friction surface (28) that is pressed radially against the casing (7).