Transport cap of a sea foundation pile, installation cradle of the transport cap of a sea foundation pile, method of installing a transport cap inside a foundation pile, towing set of sea foundation piles, method of sea towage foundation piles and preparation of a foundation pile for installation in the seabed

A method for installing a transport cap inside a foundation pile using an installation cradle, the method comprising the steps of:

• placing axially the installation cradle (17) having a bed diameter (23) equal to a pile diameter (29) at the pile base (29 using a lifting device,
• placing a pneumatic plug (1) of the pile (17),
• pumping air inside the plug (1) to a pressure not less than 10% higher from a current atmospheric pressure surrounding the plug (1), and
• pumping water into a water system (26);
• flowing the water through nozzles (25);
• wherein when the water pumped through the nozzles (25) begins to flow into the pile (29), the transport the cap (1) stabilizes in position and moves into the pile (29) and pressurizes inside the transport cap (1) to seal the inside of the pile (29) with the plug (1).

A towing set for sea foundation piles provided with a tendon and catches comprising:

• a steel tendon (31) covered with a cylinder-shaped elastomeric shield (32);
• wherein the cylindrical shield (32) is made of a flexible material optionally reinforced with fibres;
• wherein at the ends of the steel tendon (31) have bumpers (33) of the shield (32);
• wherein the tendon (31) has at the ends catch elements in the form of hooks or shackles enabling the towing set (30) to be attached to the towing ship and the towed pile on the other side.

A method of preparing a foundation pile for installation in the seabed towed by a wet method in a set of piles, behind the tug, the method comprising the steps of:

• disconnecting pile (29) with caps (1) from a towed set of piles and towed a the place of foundation installation;
• disconnecting a towing set (30) hunging on a mooring buoy;
• and
• preparing a foundation by the following phases:
• annealing a valve control cable (34), caps WR and R in a lower part of the pile (29);
• removing the air until the caps WR and R are free to move inside the pile (29);
• beginning to upright the pile (29) automatically, the bottom of the pile plunges under the water surface, and the caps WR and R lift inside the pile (29), displaced by the water flowing from the bottom;
• catching an outer cap D at the top of the pile with a crane sling and the caps D and WD in the upper part of the pile (29) are annealed by means of the valve control cable (34) and the air until the caps D and WD can freely slide inside the pile (29);
• gradually submerging the vertical pile (29) and suspending the caps (1) on the crane are successively removed from the inside of the pile (29);
• vertically placing the pile (29) on the seabed.