An arrangement and a method for installing a propulsion unit to a hull of a ship. The propulsion unit comprises an upper part of the propulsion unit attachable to the hull of the ship and a lower part of the propulsion unit where to a propeller shaft is rotatably supported, and the upper part of the propulsion unit having flanges to attach the flanges tightly to the hull, and wherein there is an aperture in bottom of hull where to the propulsion unit is to be installed. The arrangement comprises a plurality of watertight covers covering openings in the bottom of hull and a plurality of watertight covers covering openings in the top of the upper part of the propulsion unit, wherein the arrangement comprises a removable hull-side cover covering at least the opening under it, and at least one removable propulsion unit side cover covering the opening under it and facing the opening, and the removable covers are bolted from the hull-side.

A method and an arrangement for sealing a propeller shaft located under water. The propeller shaft is arranged at a pod of a ship and an air chamber is provided circumferentially around the propeller shaft. The method includes supplying compressed air from a compressed air source to the air chamber, discharging compressed air from the air chamber in an air return line and colleting liquid present in the compressed air discharged from the air chamber in an intermediate leakage tank that is provided in the air return line. The method includes closing the air return line upstream of the intermediate leakage tank, and supplying compressed air to the intermediate leakage tank to effect flowing of liquid present in the intermediate leakage tank to a leakage tank.

External loading test apparatus having a test subsystem includes a structure with at least three pillars supporting a platform, the platform being configured to receive a podded electric propulsion motor in a hanging position while allowing operation of said pod, and the test subsystem for applying a force on the pod to simulate full scale external loading. The test subsystem comprises a pod actuator interface, an actuator, and an actuator structure interface.

A marine vessel capable of improving propulsion efficiency for the entire operation of the marine vessel. In the marine vessel, which includes a hull and a propeller provided on a stern side of the hull, n.sup.2D/√(Bd) is 4 or more and 35 or less, in a case where n is the number of the propeller, D is a diameter of the propeller, B is a water line breadth of the hull, and d is a draft of the hull.

A vessel (1) comprises a hull (2) including a bow (3) and a stern (4) and has a length-to-beam ratio which is smaller than 10:1, preferably smaller than 5:1. The hull (2) has a vertical centre plane (CP) extending in a direction from the bow (3) to the stern (4). At each side of the centre plane (CP) the vessel (1) has at least two azimuth thrusters (6) including respective propellers (6a), which azimuth thrusters (6) are located next to each other in transverse direction of the centre plane (CP). Each azimuth thruster (6) drivably coupled to its own prime mover (7).

A system for offshore production of LNG from an FLNG vessel includes a floating LNG vessel including a hull and a deck, a topsides hydrocarbon processing facility installed at or above the deck of the hull of the FLNG vessel, a FLNG vessel cargo containment system comprising one or more insulated FLNG vessel cryogenic storage tanks installed within the hull of the FLNG vessel, a dynamic positioning control system operatively associated with a system of thrusters onboard the FLNG vessel where the dynamic positioning control system maintains the FLNG vessel at a desired heading around a station keeping point during LNG cargo offloading operations, and a computer processor for receiving a set of real-time monitored environmental data.

An assembly for a retractable thruster suitable for attachment to the hull of a maritime vessel. The assembly comprises a thruster accommodating structure from which the thruster may be deployed into and retracted from the water. The thruster accommodating structure is provided with a drive assembly that suspends the thruster and further comprises a thruster deploying and retracting device, a thruster rotating device, a motor assembly, and a switching device. The same drive assembly is used for deploying, retracting, and rotating the thruster.

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.

An improved amphibious vehicle comprising: a drive train; a plurality of ground engaging wheels; a cooling system; a water propulsion system; and a hull which defines a passenger compartment, wherein the form/shape of the hull below the waterline is substantially defined by a plurality of buoyancy modules that are demountably mountable to the amphibious vehicle.

A support strut has an upper end rotatable supported at a bottom of a vessel and a lower end supporting a casing. A first electric motor within the casing drives a propeller via a first shaft. An annular nozzle surrounds an outer perimeter of the propeller and is fixedly supported on the casing, with a support construction comprising at least three vanes extending in the radial direction between the outer perimeter of the casing and the inner perimeter of the nozzle. A duct for water flow is formed through the interior of the annular nozzle. The propeller pulls the vessel in a driving direction. The vanes are positioned after the propeller in the driving direction of the vessel, whereby the vanes are optimized for redirecting rotational flow components of the flow produced by the propeller into axial thrust.