Sealing arrangement, and corresponding method

摘要

A sealing arrangement and method for dynamic sealing around a drill stem (50) in water-carrying, drilling fluid-carrying or hydrocarbon-carrying wells, comprising at least one dynamic sealing (35a) which is arranged to envelop the drill stem (50), and a receiver unit (30) arranged to receive the at least one sealing (35a), with the dynamic sealing being arranged to be driven into the receiver unit (30) with the help of the drill stem, and to be securely locked in the receiver unit, and also that internal pressure support in the sealing arrangement is provided corresponding to at least the surrounding pressure. The receiver unit (30) is arranged in an area in or near the drill deck of a drilling rig or vessel and in a riser, landing string or in another connection between drill deck and a well to close the return side of the drilling fluid between the drill stem and upper part of the riser, with the receiver unit (30), in connection with a floating rig or drilling ship, being arranged below the compensating unit (21) of the riser to make movement compensation possible between riser (20) and surface vessel (10), or that the receiver unit (30) in connection with a fixed installation, is arranged as a part of the riser connection (20).

主权项

1. Method for dynamic sealing around a drill stem and an upper part of a riser in water-carrying, drilling fluid-carrying or hydrocarbon-carrying wells, having a sealing arrangement for a dynamic sealing comprising at least one dynamic seal placed to envelop the drill stem in the riser for closing a drilling fluid return side between the drill stem and the upper part of the riser, with an internal pressure support being provided in the sealing arrangement the method comprising
assembling a receiver unit in the riser in which the receiver unit in connection with a floating rig or drilling ship, is arranged below a compensating unit of the riser; running the drill stem into the riser with a suspended sealing unit; entering and securely locking the sealing unit to the receiver unit which is mounted as a part of the connection to the well; running subsequent seals suspended on the drill stem without removal of the first installed seal, and securely locking said seals with the help of respective locking devices at mutually spaced apart locations longitudinally in the receiver unit; testing and verifying each seal with pressure testing; and injecting pressure medium through dedicated lines in the receiver unit to provide pressure support for the seals.