Abstract: A system and method of starting a water jet propulsion system for a ship in which the propulsion system includes a stator shell adapted to be mounted to the hull and having a nozzle ending in an outlet with a cross-sectional outlet area, an impeller housing attached to the stator shell and having an upstream inlet, and an impeller rotatably mounted in the impeller housing for receiving water from the inlet and discharging it through the nozzle of the stator shell so as to create a water jet upon rotation of the impeller. The method includes reducing the outlet area by partly closing the nozzle during a start up phase of the water jet propulsion system, wherein there is provided a back flow hindering arrangement arranged to hinder air to enter into the impeller housing via the nozzle.

Abstract: A system and method of starting a water jet propulsion system for a ship in which the propulsion system includes a stator shell adapted to be mounted to the hull and having a nozzle ending in an outlet with a cross-sectional outlet area, an impeller housing attached to the stator shell and having an upstream inlet, and an impeller rotatably mounted in the impeller housing for receiving water from the inlet and discharging it through the nozzle of the stator shell so as to create a water jet upon rotation of the impeller. The method includes reducing the outlet area by partly closing the nozzle during a start up phase of the water jet propulsion system, wherein there is provided a back flow hindering arrangement arranged to hinder air to enter into the impeller housing via the nozzle.

Abstract: The present invention relates to a steering arrangement for ships propelled by water jet, comprising a steering device (6) that is pivotal about an essentially vertical shaft (5) having a first center line (C1), at least one hydraulic cylinder (2; 3) for turning said steering device (6), which hydraulic cylinder is directly or indirectly articulately connected to the ship's body at one of its ends (2B; 3B), a turning device (4) connected to said shaft (5), for attachment to a second end (2A; 3A) of said hydraulic cylinder at a distance from said shaft (5), a reversing device (7) arranged in connection with said steering device (6) about an essentially horizontal shaft (12), an additional hydraulic cylinder (9) arranged to act on the reversing device (7), the additional hydraulic cylinder (9) following the movement of the steering device (6), characterized in that all the hydraulic cylinders (2,3,9) are arranged within a sheltered space (1) located above the extension of said vertical shaft (5), which space (1

Abstract: The present invention relates to a steering arrangement for ships with a water jet unit, comprising a steering device that is pivotable about an essentially vertical shaft having a first center line, at least one hydraulic cylinder articulately connected at a first end of the hydraulic cylinder to the attachment flange of the water jet unit, a turning device connected to the shaft for attachment to a second end of the hydraulic cylinder at a distance from the shaft, a reversing device for pivoting the steering device, the reversing device being arranged about an essentially horizontal shaft, an additional hydraulic cylinder arranged to act on the reversing device, the additional hydraulic cylinder following the movement of the steering device, characterized in that all the hydraulic cylinders are arranged within a sheltered space located above the extension of the vertical shaft.

Abstract: The present invention relates to a steering arrangement for ships propelled by water jet, comprising a steering device (6) that is pivotal about an essentially vertical shaft (5) having a first centre line (C1), at least one hydraulic cylinder (2; 3) for turning said steering device (6), which hydraulic cylinder is directly or indirectly articulately connected to the ship's body at one of its ends (2B; 3B), turning device (4) connected to said shaft (5), for attachment to a second end (2A; 3A) of said hydraulic cylinder at a distance from said shaft (5), a reversing device (7) arranged in connection with said steering device (6) about an essentially horizontal shaft (12), an additional hydraulic cylinder (9) arranged to act on the reversing device (7), the additional hydraulic cylinder (9) following the movement of the steering device (6), characterised in that all the hydraulic cylinders (2,3,9) are arranged within a sheltered space (1) located above the extension of said vertical shaft (5), which space (1)

Abstract: The invention comprises a propulsion system for ships comprising an impeller (13, 14), a stator shell (1), and a impeller housing (3) for achieving a waterjet, a shaft (11, 12) for the propulsion of the impeller (13), and a bearing arrangement for the shaft (11, 12) in the stator shell (1), and preferably a sealing (15) of the shaft (11, 12) in the impeller housing (3), wherein said bearing arrangement comprises at least one sliding bearing unit (25; 26) intended to carry axial load, and which sliding bearing preferably is water lubricated.

Abstract: A propulsion system for ships having an impeller (13, 14), a stator shell (1), and an impeller housing (3) for achieving a water jet, a shaft (11, 12) for the propulsion of the impeller (13), and a bearing arrangement for the shaft (11, 12) in the stator shell (1), and preferably a sealing (15) of the shaft (11, 12) in the impeller housing (3), wherein the shaft (11, 12) consists of a light weight shaft, which has considerably lower bending rigidity than a homogenous, conventional steel shaft, and the driving force is transmitted via at least one non-flexible coupling (11B, 12A) and via the bearing arrangement which is rigid as to bending and handles the axial load, to the stator shell (1), such that a high power density is achieved.

Abstract: The present invention relates to a steering arrangement for ships with water jet unit, comprising a steering device that is pivotable about an essentially vertical shaft having a first centre line, at least one hydraulic cylinder articulately connected at a first end of the hydraulic cylinder to the attachment flange of the water jet unit, a turning device connected to said shaft for attachment to a second end of said hydraulic cylinder at a distance from said shaft, a reversing device for pivoting the steering device, the reversing device being arranged about an essentially horizontal shaft, an additional hydraulic cylinder arranged to act on the reversing device, the additional hydraulic cylinder following the movement of the steering device, characterized in that all the hydraulic cylinders are arranged within a sheltered space located above the extension of said vertical shaft.

Abstract: The invention comprises a propulsion system for ships comprising an impeller (13, 14), a stator shell (1), and a impeller housing (3) for achieving a waterjet, a shaft (11, 12) for the propulsion of the impeller (13), and a bearing arrangement for the shaft (11, 12) in the stator shell (1), and preferably a sealing (15) of the shaft (11, 12) in the impeller housing (3), wherein said bearing arrangement comprises at least one sliding bearing unit (25; 26) intended to carry axial load, and which sliding bearing preferably is water lubricated.