Patent ID: 7992275

Claim:
A method for lifting thrusters on floating vessels for floating vessel transit, for floating vessel dry docking, for thruster maintenance, or combinations thereof, the method comprising: a. forming a thruster well with a thruster well wall and a thruster well bottom flange for engagement with a thruster mounting flange of a thruster, wherein the thruster at least partially extends into water through a hull of a floating vessel; b. installing a plurality of alignment guide plates concentrically around the thruster in the thruster well, wherein each alignment guide plate extends from proximate the thruster well bottom flange to a thruster well wall top of the thruster well wall to provide a rough alignment of the thruster mounting flange to the thruster well bottom flange; c. positioning a least one seal adjacent the thruster mounting flange to provide a water tight connection between the thruster well bottom flange and the thruster mounting flange; d. installing a plurality of fasteners to secure the thruster mounting flange to the thruster well bottom flange while compressing the at least one seal; e. forming a plurality of clevises on an inside surface of the thruster well wall; f. fastening a plurality of clamps to the thruster well wall using the plurality of clevises, wherein each clamp has an actuator adapted to extend and retract and a linkage connected to the actuator; g. maintaining each of the clamps in an open position during normal thruster operation, and during removal of the thruster: actuating each clamp to extend to a closed position to secure the thruster mounting flange to the thruster well bottom flange while compressing the at least one seal; h. lowering a flexible lift line and a connector of a lifting means into the thruster well, and engaging the connector with a lifting eye of the thruster or with a lifting eye of a portion of the thruster; i. raising the thruster or the portion of the thruster out of the thruster well using the lifting means; j. transporting the thruster or the portion of the thruster using a moveable transport device connected to the lifting means to a deck of the floating vessel; k. actuating each of the plurality of clamps to extend to hold the thruster mounting flange against the thruster well bottom flange and to ensure that the at least one seal remains compressed, and while the clamps are actuated, removing the plurality of fasteners that secure the thruster mounting flange to the thruster well bottom flange; l. flooding the thruster well with water; m. disengaging the plurality of clamps; and n. lifting the thruster with the lifting means.