Abstract: An arrangement including a gearwheel connected to the propulsion unit, a steering electric motor operatively connected to the gearwheel and controlled by a drive, a force transmission arrangement including a clutch between the gearwheel and the steering electric motor, and a measurement unit for measuring rotational motion positioned at each side of the clutch. The steering electric motor is arranged to rotate the gearwheel and thereby also the propulsion unit. A difference in the output signals of the two measuring units indicating slipping of the clutch is detected. The steering electric motor is controlled to at least reduce the difference in the output signals when the difference exceeds a predetermined threshold.

Abstract: An arrangement including a gearwheel connected to the propulsion unit, a steering electric motor operatively connected to the gearwheel and controlled by a drive, a force transmission arrangement including a clutch between the gearwheel and the steering electric motor, and a measurement unit for measuring rotational motion positioned at each side of the clutch. The steering electric motor is arranged to rotate the gearwheel and thereby also the propulsion unit. A difference in the output signals of the two measuring units indicating slipping of the clutch is detected. The steering electric motor is controlled to at least reduce the difference in the output signals when the difference exceeds a predetermined threshold.

Abstract: The arrangement comprises a seal (500) sealing a cylindrical rotating part (100) passing through an opening in a support structure in the vessel (10) against a medium (W). The seal (500) comprises a package of annular seal rings (510, 520, 530). Each seal ring (510, 520, 530) comprises a seal part (512, 522, 532) being supported in a corresponding seal support part (511, 521, 531). The seal support part (511) in the first seal ring (510) positioned closest to the medium (W) has the form of a cylinder (511A) provided with an annular flange (511B) at one end of the cylinder (511A). The outer surface of the cylinder (511A) is supported and sealed with an auxiliary seal (610) against the inner circumference of the opening. The annular flange (511B) is supported against the support structure (83) surrounding the opening.

Abstract: The propulsion unit comprises a strut having an upper portion with an upper end portion passing through a passage formed between a first outer bottom and a second inner bottom in a vessel. The upper end portion is rotatable supported with a slewing bearing and sealed with a slewing seal. An upper slewing seal prevents lubrication medium leakage from the slewing bearing, whereby access to the upper slewing seal is provided in a radial direction from the interior of the vessel or from the interior of the strut in order to be able to service the upper slewing seal. A lower slewing seal is positioned at a vertical distance below the upper slewing seal and prevents sea water from penetrating into the hull of the vessel, whereby access to the lower slewing seal is provided in a radial direction from the interior of the vessel or from the interior of the strut in order to be able to service the lower slewing seal.

Abstract: A propulsion unit is disclosed with a hollow strut having an upper portion with an upper end portion passing through a passage (P1) formed between a first outer bottom and a second inner bottom in a vessel. The upper end portion is rotatably supported with a slewing bearing and sealed with a slewing seal towards the vessel. A cooling arrangement includes a cooling air duct system, at least one fan and at least one cooling unit. The slewing seal can include an upper slewing seal and a lower slewing seal at a vertical distance (H1) from each other with a space formed between the slewing seals. The upper end portion has openings (O1) into the space between the slewing seals. A first cooling air duct is directed to this space, whereby cooling air (L1) can be circulated through the first cooling air duct (400) into the space and through the openings (O1) in the upper end portion to the interior of the strut, or return air (L2) can be circulated from the strut in an opposite direction.

Abstract: The propulsion unit comprises a strut having an upper portion with an upper end portion passing through a passage formed between a first outer bottom and a second inner bottom in a vessel. The upper end portion is rotatable supported with a slewing bearing and sealed with a slewing seal. An upper slewing seal prevents lubrication medium leakage from the slewing bearing, whereby access to the upper slewing seal is provided in a radial direction from the interior of the vessel or from the interior of the strut in order to be able to service the upper slewing seal. A lower slewing seal is positioned at a vertical distance below the upper slewing seal and prevents sea water from penetrating into the hull of the vessel, whereby access to the lower slewing seal is provided in a radial direction from the interior of the vessel or from the interior of the strut in order to be able to service the lower slewing seal.

Abstract: The arrangement comprises a seal (500) sealing a cylindrical rotating part (100) passing through an opening in a support structure in the vessel (10) against a medium (W). The seal (500) comprises a package of annular seal rings (510, 520, 530). Each seal ring (510, 520, 530) comprises a seal part (512, 522, 532) being supported in a corresponding seal support part (511, 521, 531). The seal support part (511) in the first seal ring (510) positioned closest to the medium (W) has the form of a cylinder (511A) provided with an annular flange (511B) at one end of the cylinder (511A). The outer surface of the cylinder (511A) is supported and sealed with an auxiliary seal (610) against the inner circumference of the opening. The annular flange (511B) is supported against the support structure (83) surrounding the opening.

Abstract: A propulsion unit is disclosed with a hollow strut having an upper portion with an upper end portion passing through a passage (P1) formed between a first outer bottom and a second inner bottom in a vessel. The upper end portion is rotatably supported with a slewing bearing and sealed with a slewing seal towards the vessel. A cooling arrangement includes a cooling air duct system, at least one fan and at least one cooling unit. The slewing seal can include an upper slewing seal and a lower slewing seal at a vertical distance (H1) from each other with a space formed between the slewing seals. The upper end portion has openings (O1) into the space between the slewing seals. A first cooling air duct is directed to this space, whereby cooling air (L1) can be circulated through the first cooling air duct (400) into the space and through the openings (O1) in the upper end portion to the interior of the strut, or return air (L2) can be circulated from the strut in an opposite direction.