Patent ID: 7985108

Claim:
A modular removable externally mountable diesel hydraulic thruster system for dynamic positioning of a floating semi-submersible vessel with a ballasted waterline comprising at least one submerged pontoon, and wherein each submerged pontoon is provided with at least one vertical column integral with a top of the at least one submerged pontoon, and wherein each vertical column supports a deck above the ballasted waterline, and wherein the modular removable externally mountable diesel hydraulic thruster system comprises: a. at least a pair of azimuthing thrusters wherein each azimuthing thruster is removably mounted to the at least one submerged pontoon of the floating semi-submersible vessel, and wherein each azimuthing thruster generates a variable thrust and each azimuthing thruster comprises: 1. a skid removably secured to the top portion of the submerged pontoon below the ballasted waterline; 2. an upper thruster housing removably connected to the skid, containing a slewing bearing with at least one hydraulic motor driven slewing drive, at least one electric steering angle feedback sensor for indicating the steering angle of the azimuthing thruster and a multiport hydraulic swivel assembly; 3. a tube moveably connected to the upper thruster housing and removable connected on the other end to a hydraulic pod with nozzle; 4. a hydraulic motor inside the hydraulic pod with a rotating propeller drive shaft whereby a fixed pitch propeller is removably mounted to a propeller drive shaft that engages the propeller drive shaft; and 5. a bundle of thruster hydraulic hose assemblies connected to at least one of the hydraulic motors on one end to the multiport hydraulic assembly on the other end; b. at least a pair of diesel hydraulic power units removably secured to the deck, wherein each diesel hydraulic power unit engages one of the azimuthing thrusters, wherein each diesel hydraulic power unit comprises: 1. a power unit housing; 2. a diesel engine driven hydraulic pump package within the power unit housing; 3. at least one hydraulic fluid reservoir; 4. a fuel tank connected to the diesel engine; 5. a cooling system; 6. a starting system connected to the diesel engine; 7. an exhaust system connected to the diesel engine; 8. a bundle of hydraulic hose assemblies, wherein at least one hydraulic hose is connected to the hydraulic motor within the hydraulic pod; and 9. a control system communicating with the azimuthing thruster; c. a dynamic positioning system connected to the diesel hydraulic power unit; and d. at least two position reference sensors and at least two environmental reference sensors connected to the dynamic positioning system.