Abstract: A ring member for a downhole apparatus including a swellable material selected to increase in volume on exposure to at least one triggering fluid is described. The ring member is configured to cooperate with a swellable member disposed on a body of the apparatus, and may, for example, function as a gauge ring or a retaining member. The ring member is secured to the apparatus via a coupling arrangement which couples the body to an adjacent well string section. In one embodiment, the ring member is threaded into the well string. In another, it is disposed over an upstanding formation such as a coupling sleeve, for example, by clamping. An assembly and a method of assembly are also described.

Abstract: A downhole apparatus is described comprising a body and a sealing arrangement located on the body. The body has a longitudinal axis and the sealing arrangement comprises at least one elongated sealing member with an axis of elongation extending around the longitudinal axis. The sealing member comprises a material selected to expand on exposure to at least one predetermined fluid, such as a hydrocarbon or aqueous fluid encountered in a wellbore. A method of forming the apparatus and methods of use are described. Embodiments of the invention relate to wellbore packers.

Abstract: A method of forming a downhole apparatus and an apparatus formed by the method is described. The method comprising the steps of providing a body having a longitudinal axis and forming an expanding portion on the body from multiple turns of a partially or substantially cured material around the longitudinal axis of the body. The material is selected to increase in volume on exposure to at least one predetermined fluid, such as a wellbore fluid. Embodiments of the invention include wellbore packers formed by the method.