Abstract: Annular packer (2) arranged on the outside of a production tubing (4) said packer comprises a core (12) comprising elastic polymer swelling by absorption of hydrocarbons. The core (12) may be surrounded by an external mantle of rubber (10), which is permeable to hydrocarbons and may be equipped with a reinforcement (11). The core (12) swells by absorption of hydrocarbons and the packer (2) expands thus in order to seal the annular space (5) between the production tubing (4) and the well wall (6).

Abstract: Annular packer (2) arranged on the outside of a production tubing (4) said packer comprises a core (12) comprising elastic polymer swelling by absorption of hydrocarbons. The core (12) may be surrounded by an external mantle of rubber (10), which is permeable to hydrocarbons and may be equipped with a reinforcement (11). The core (12) swells by absorption of hydrocarbons and the packer (2) expands thus in order to seal the annular space (5) between the production tubing (4) and the well wall (6).

Abstract: Annular packer (2) arranged on the outside of a production tubing (4) said packer comprises a core (12) comprising elastic polymer swelling by absorption of hydrocarbons. The core (12) may be surrounded by an external mantle of rubber (10), which is permeable to hydrocarbons and may be equipped with a reinforcement (11). The core (12) swells by absorption of hydrocarbons and the packer (2) expands thus in order to seal the annular space (5) between the production tubing (4) and the well wall (6).

Abstract: Annular packer (2) arranged on the outside of a production tubing (4) said packer comprises a core (12) comprising elastic polymer swelling by absorption of hydrocarbons. The core (12) may be surrounded by an external mantle of rubber (10), which is permeable to hydrocarbons and may be equipped with a reinforcement (11). The core (12) swells by absorption of hydrocarbons and the packer (2) expands thus in order to seal the annular space (5) between the production tubing (4) and the well wall (6).

Abstract: Annular packer (2) arranged on the outside of a production tubing (4) said packer comprises a core (12) comprising elastic polymer swelling by absorption of hydrocarbons. The core (12) may be surrounded by an external mantle of rubber (10), which is permeable to hydrocarbons and may be equipped with a reinforcement (11). The core (12) swells by absorption of hydrocarbons and the packer (2) expands thus in order to seal the annular space (5) between the production tubing (4) and the well wall (6).

Abstract: Annular packer (2) arranged on the outside of a production tubing (4) said packer comprises a core (12) comprising elastic polymer swelling by absorption of hydrocarbons. The core (12) may be surrounded by an external mantle of rubber (10), which is permeable to hydrocarbons and may be equipped with a reinforcement (11). The core (12) swells by absorption of hydrocarbons and the packer (2) expands thus in order to seal the annular space (5) between the production tubing (4) and the well wall (6).

Abstract: Annular packer (2) arranged on the outside of a production tubing (4) said packer comprises a core (12) comprising elastic polymer swelling by absorption of hydrocarbons. The core (12) may be surrounded by an external mantle of rubber (10), which is permeable to hydrocarbons and may be equipped with a reinforcement (11). The core (12) swells by absorption of hydrocarbons and the packer (2) expands thus in order to seal the annular space (5) between the production tubing (4) and the well wall (6).

Abstract: Annular packer (2) arranged on the outside of a production tubing (4) said packer comprises a core (12) comprising elastic polymer swelling by absorption of hydrocarbons. The core (12) may be surrounded by an external mantle of rubber (10), which is permeable to hydrocarbons and may be equipped with a reinforcement (11). The core (12) swells by absorption of hydrocarbons and the packer (2) expands thus in order to seal the annular space (5) between the production tubing (4) and the well wall (6).

Abstract: A downhole tool for pressure testing of oil and gas wells comprises a generally tubular main tool (1), which is provided with an internal passage (2) and is arranged for attachment at the lower end of a drill pipe string. The main tool (1) is on its outside provided with an inflatable packing element (10), which may be supplied with and relieved of inflating medium via an annular slide valve (5) arranged inside the main tool (1). The slide valve has two active positions, one on each side of a closing initial position, and the slide valve is brought to the active positions by an auxiliary tool (18) which may be run into the passage (2) of the main tool and attached releasably in the slide valve (5).

Abstract: A method for movement-compensating a riser pipe (6) running between a mobile offshore structure (7, 8) and a wellhead (2) on the sea-bed (1), employs a sliding joint (13, 15) in the form of a telescopic device (9) which is volume and pressure balanced. This balancing makes it possible to use the sliding joint under the extreme conditions of pressure which may be experienced in production riser pipes, which the advantage that the production systems may be fitted fixedly to the mobile offshore structure. The method also combines the sliding joint (13, 15) with a hydraulic cylinder (27) which maintains a movement-compensated tension in the riser pipe (6). Several examples of slidng joints (13, 15) with movement-compensated tension cylinders (27, 38, 43) are shown.