A truss-like hydraulic lifting apparatus with plugs including a pile reinforcing frame, a truss structure extending through and mounted within the pile reinforcing frame and a first number of uniformly disposed support legs, each having a support leg inserting hole. A first number of power source devices each has a plug corresponding to the support leg inserting hole. A detachable mechanism is provided for detachably fixing each of the power source devices to the pile reinforcing frame. The detachable mechanism includes a base plate laterally fixed relative to the pile reinforcing frame and having an opening through which the support leg vertically passes and forms a protective cap above the power source device. The lateral dimension of the protective cap is larger than the lateral dimension of the power source device.

A truss-like hydraulic lifting apparatus with plugs including a pile reinforcing frame, a truss structure extending through and mounted within the pile reinforcing frame and a first number of uniformly disposed support legs, each having a support leg inserting hole. A first number of power source devices each has a plug corresponding to the support leg inserting hole. A detachable mechanism is provided for detachably fixing each of the power source devices to the pile reinforcing frame. The detachable mechanism includes a base plate laterally fixed relative to the pile reinforcing frame and having an opening through which the support leg vertically passes and forms a protective cap above the power source device. The lateral dimension of the protective cap is larger than the lateral dimension of the power source device.

An offshore platform lifting device for lifting operations at sea after sailed to a certain position of a sea surface includes an upper deck, a plurality of upright columns, a rail seat, a base disposed on the rail seat, two davit arms, two first winches, and two second winches. The upper deck has a lower pontoon. The upright columns are connected between to the upper deck and the lower pontoon. Each upright column is provided with a support leg that is longitudinally inserted through the upright column, thereby positioning the offshore platform lifting device on the seabed through the upright columns. The two davit arms are disposed the base and drives the base to move laterally through a pushing device. The two second winches each have a second cable passing through the two davit arms. A hook is disposed at a distal end of the second cable.

An offshore platform lifting device for lifting operations at sea after sailed to a certain position of a sea surface includes an upper deck, a plurality of upright columns, a rail seat, a base disposed on the rail seat, two davit arms, two first winches, and two second winches. The upper deck has a lower pontoon. The upright columns are connected between to the upper deck and the lower pontoon. Each upright column is provided with a support leg that is longitudinally inserted through the upright column, thereby positioning the offshore platform lifting device on the seabed through the upright columns. The two davit arms are disposed the base and drives the base to move laterally through a pushing device. The two second winches each have a second cable passing through the two davit arms. A hook is disposed at a distal end of the second cable.

A semi-submersible support platform and a positioning method thereof are disclosed. The semi-submersible support platform, used for operations at sea after sailed to a certain position of a sea surface, includes an upper deck and a lower pontoon. The upper deck and the lower pontoon are connected by a plurality of upright columns. Each upright column is provided with a support leg that is longitudinally inserted through the upright column. The lower pontoon has a plurality of chambers for receiving water therein. The support leg has a compartment for receiving water therein. Each upright column includes a leveling mechanism therein. When the support leg sinks to reach the seabed, the leveling mechanism in each upright column is combined with the support leg to support the support leg. The leveling mechanism can drive the upper deck to move up or down along the support leg.

An underwater operation platform, including: a main body; two ducted propellers disposed at the tail end of the main body; a living building; pile legs; a tower crane; a submergence module; lifting devices; and a gantry crane. The main body includes a deck and a moonpool. The submergence module includes a support plate, a plurality of truss members, and a base plate. The living building disposed on the front end of the deck. The pile legs are disposed at the four corners of the main body, respectively. The deck includes two parallel pathways which are located at two sides of the moonpool, respectively, for supporting the gantry crane. The lifting devices are disposed on the deck and are close to four corners of the moonpool. The support plate and the base plate are integrated with the plurality of truss members.

An underwater operation platform, including: a main body; two ducted propellers disposed at the tail end of the main body; a living building; pile legs; a tower crane; a submergence module; lifting devices; and a gantry crane. The main body includes a deck and a moonpool. The submergence module includes a support plate, a plurality of truss members, and a base plate. The living building disposed on the front end of the deck. The pile legs are disposed at the four corners of the main body, respectively. The deck includes two parallel pathways which are located at two sides of the moonpool, respectively, for supporting the gantry crane. The lifting devices are disposed on the deck and are close to four corners of the moonpool. The support plate and the base plate are integrated with the plurality of truss members.

A self-elevating platform comprises a deck structure, a plurality of legs, a plurality of footings, and a jacking system, wherein the plurality of legs pass through the deck structure and are supported by the plurality of footings; and wherein the jacking system comprises a jackcase structure with a first locking pin, a jacking yoke with a second locking pin, a plurality of jacking cylinders with a first end and second end, where the first end of the jacking cylinders is supported by the jackcase structure, and the second end of the jacking cylinders by the jacking yoke; and a fixation system comprising a plurality of tension rods, wherein each tension rod has a first end and a second end, and wherein the first end of the tension rods is securely coupled with the jacking yoke, and the second end of the tension rods is securely coupled with the deck structure; thereby when the plurality of tension rods secures the jacking yoke to the deck structure, the load can be removed from the hydraulic cylinders and transferred to the fixation system.

A self-elevating platform comprises a deck structure, a plurality of legs, a plurality of footings, and a jacking system, wherein the plurality of legs pass through the deck structure and are supported by the plurality of footings; and wherein the jacking system comprises a jackcase structure with a first locking pin, a jacking yoke with a second locking pin, a plurality of jacking cylinders with a first end and second end, where the first end of the jacking cylinders is supported by the jackcase structure, and the second end of the jacking cylinders by the jacking yoke; and a fixation system comprising a plurality of tension rods, wherein each tension rod has a first end and a second end, and wherein the first end of the tension rods is securely coupled with the jacking yoke, and the second end of the tension rods is securely coupled with the deck structure; thereby when the plurality of tension rods secures the jacking yoke to the deck structure, the load can be removed from the hydraulic cylinders and transferred to the fixation system.

A jackup mobile offshore drilling unit includes a hull and a plurality of jacking legs movable longitudinally with respect to the hull and having features thereon to support the hull above a body of water. A storage tank is disposed inside at least one of the plurality of jacking legs. The unit comprises means for moving the storage tank longitudinally inside the at least one of the plurality of jacking legs.