Abstract: An installation of bottom-to-surface connections having a plurality of bottom-to-surface connections arranged in a fan from a common floating support. The installation having a first number k of first bottom-to-surface connections, with each first number of connections having a first riser connected to a first undersea pipe tensioned in substantially vertical manner by a first float, and a diving first flexible connection pipe connecting the floating support and first riser. The installation further having a second number m of second bottom-to-surface connection, with each second number of connections having a second rigid pipe connected to a second undersea pipe and tensioned by a second buoyancy element, and a second flexible connection pipe providing the connection between the floating support and the second rigid pipe.

Abstract: An installation of bottom-to-surface connections having a plurality of bottom-to-surface connections arranged in a fan from a common floating support. The installation having a first number k of first bottom-to-surface connections, with each first number of connections having a first riser connected to a first undersea pipe tensioned in substantially vertical manner by a first float, and a diving first flexible connection pipe connecting the floating support and first riser. The installation further having a second number m of second bottom-to-surface connection, with each second number of connections having a second rigid pipe connected to a second undersea pipe and tensioned by a second buoyancy element, and a second flexible connection pipe providing the connection between the floating support and the second rigid pipe.

Abstract: A bottom-surface connection installation for at least two undersea pipes resting on the sea bottom, the installation comprising: a first hybrid tower having a vertical riser anchored to a first base and connected to an undersea pipe resting on the sea bottom and having its top end connected to a first float below the surface, and a first connection pipe, preferably a flexible pipe, providing a connection between a floating support and the top end of said riser; and at least one second rigid pipe rising from the sea bottom where it rests or from a second undersea pipe resting on the sea bottom and to which its bottom end that is not anchored to said first base is connected, up to below the surface, where its top end is connected to a second float situated at substantially the same depth as said first float, and fastened to said first float to at least one respective said connection pipe that is flexible and serves to connect it to the same said floating support.

Abstract: A bottom-surface connection installation for at least two undersea pipes resting on the sea bottom, the installation comprising: a first hybrid tower having a vertical riser anchored to a first base and connected to an undersea pipe resting on the sea bottom and having its top end connected to a first float below the surface, and a first connection pipe, preferably a flexible pipe, providing a connection between a floating support and the top end of said riser; and at least one second rigid pipe rising from the sea bottom where it rests or from a second undersea pipe resting on the sea bottom and to which its bottom end that is not anchored to said first base is connected, up to below the surface, where its top end is connected to a second float situated at substantially the same depth as said first float, and fastened to said first float to at least one respective said connection pipe that is flexible and serves to connect it to the same said floating support.

Abstract: A method for triggering and controlling lateral bucking in underwater pipelines by installation of supporting systems, positioned in certain points of the seabed. Upper surfaces of the supports, on which the pipelines rest, are tilted with respect to the horizontal plane, and transversally with respect to the direction of the pipelines.

Abstract: Apparatus for heating and lagging at least one main undersea pipe for conveying a flow of hot effluent. The apparatus includes a covering of thermally insulating material surrounding the main pipe(s), and covered by a leaktight outer protective casing and an internal chamber coaxial with the outer casing. The insulating covering surrounds the internal chamber in an annular space between the outer casing and the internal chamber. The main pipe is contained inside an internal chamber that is preferably cylindrical in shape. A heat-transfer fluid having a maintained temperature surrounds the main pipe contained inside the internal chamber and is circulated inside the internal chamber.

Abstract: Apparatus for heating and lagging at least one main undersea pipe for conveying a flow of hot effluent. The apparatus includes a covering of thermally insulating material surrounding the main pipe(s), and covered by a leaktight outer protective casing and an internal chamber coaxial with the outer casing. The insulating covering surrounds the internal chamber in an annular space between the outer casing and the internal chamber. The main pipe is contained inside an internal chamber that is preferably cylindrical in shape. A heat-transfer fluid having a maintained temperature surrounds the main pipe contained inside the internal chamber and is circulated inside the internal chamber.

Abstract: A bottom-to-surface connection installation for an undersea pipe. The installation comprises a vertical riser having its bottom end connected to an undersea pipe on the sea bed, and having a float at its top end, and a pipe connecting a floating support at the top end of the vertical riser. The connection between the riser bottom end and the undersea pipe is via an anchor system having a base on the sea bed. The base holds and guides junction elements between the bottom end of the riser and the end of the lower end of the undersea pipe. The junction elements comprise a rigid pipe element presenting an angled bend and a pipe coupling element which are fixed to a moving support of the base. The junction elements are fixed to the moving support and are free to move only in translation in a single longitudinal direction.

Abstract: A bottom-to-surface connection installation for an undersea pipe. The installation comprises a vertical riser having its bottom end connected to an undersea pipe on the sea bed, and having a float at its top end, and a pipe connecting a floating support at the top end of the vertical riser. The connection between the riser bottom end and the undersea pipe is via an anchor system having a base on the sea bed. The base holds and guides junction elements between the bottom end of the riser and the end of the lower end of the undersea pipe. The junction elements comprise a rigid pipe element presenting an angled bend and a pipe coupling element which are fixed to a moving support of the base. The junction elements are fixed to the moving support and are free to move only in translation in a single longitudinal direction.

Abstract: This invention provides a seismic joint for an underwater floating tunnel having: (a) a joint portion (i) having a transverse section essentially the same as that of the tunnel, (ii) being rigidly fastened to land at one end (A) thereof, and (iii) being elastically constrained to the tunnel at its other end (B) via a plurality of operably affixed means which performs an elastic function and a damping function; (b) a collar welded onto the external surface of the tunnel facing end (B) of the portion, said collar being capable of sliding on and along the external surface of the joint portion; and (c) a means for providing a water-tight seal between the internal surface of the collar and the external surface of the joint portion.