Tensioner for applying tension to riser, has annular lubricant reservoir mounted to interior wall surface of inner barrel that is telescopingly engaged with outer barrel

摘要

A tensioner has an annular lubricant reservoir (25) mounted to the interior wall surface of an inner barrel (19) that is telescopingly engaged with an outer barrel (13). A lubricant port (33) extends from the reservoir through the inner barrel to the exterior wall surface of the inner barrel for dispensing lubricant between the inner and outer barrels. Independent claims are also included for the following: (i) a further tensioner for an offshore structure, comprising: inner and outer barrels engaging each other for movement between retracted and extended positions, each having a closed end and an open end communicating interiors of the barrels with each other; a gas port for introducing gas pressure to the interiors of the barrels, urging the barrels toward the extended position; a primary seal between the inner and outer barrels at the open end of the inner barrel for sealing the gas pressure within the interiors of the barrels; an annular lubricant reservoir mounted to an interior wall surface of the inner barrel at the open end of the inner barrel, the reservoir having an interior in fluid communication with the gas pressure in the interiors of the barrels; and a lubricant port extending from the lubricant reservoir through the inner barrel to a high pressure side of the primary seal for dispensing lubricant between the inner and outer barrels; and (ii) applying tension to a sub-sea structure, by mounting a lubricant reservoir to an interior wall surface of an inner barrel and forming a lubricant port from the lubricant reservoir through the interior wall surface of the inner barrel, placing the inner barrel into an outer barrel; connecting the subsea member to one of the barrels and the offshore structure to the other of the barrels, pressurizing interiors of the inner and outer barrels to urge the barrels to an extended position relative to each other, and introducing lubricant to the lubricant reservoir, which flows through the lubricant port to lubricate between the inner and outer barrels as they move relative to each other.