Abstract: The nacelle (3) is characterized in that it includes at least one cable (6) having a top end that leaves the nacelle upwardly and a bottom end that leaves the nacelle downwardly, and a mechanism (11) enabling the nacelle to move up and down the cable when the top end of the cable is hooked to a hook unit (4). A mechanism enables the top portion of the cable to be subjected to a tension greater than the weight of the nacelle while the bottom portion (7) of the cable is fixed to an anchor point, said tensioning mechanism serving to vary the distance between the nacelle (3) and said hook unit at the top end of the cable. Further, mechanism (12, 14) acts on command, on said tensioning mechanism in such a manner as to prevent the distance between the nacelle (3) and the hook unit (4) at the top end of the cable from shortening while not preventing it from lengthening.

Abstract: A device for positioning and applying tension to a set of rods (5) for holding a partially submerged platform wherein the device includes a metal frame, (12, 13A, 13B, 13C, 13D, 14), means for vertically moving said frame relative to the platform, at least one jack (21 22) of a first type which has a cylinder and a rod, at least one jack (31,32) of a second type which has a cylinder and a rod, the cylinders of the rods being fast to said frame and being disposed in such a way that the rods move vertically, the rod of the jack of the first type being fast to a plate (25) which is provided firstly with an orifice for the rod of the second type of jack to pass through and secondly with means of fixing to the end of the set of rods, the rod of the second type of jack having a stop (31, 32) at its end, the rods of the jacks of both types being of unequal length and being chosen in such a way that the jack of the second type drives the plate only in the platform immersion step. Application to oil well drilling.

Abstract: This connection means comprises a male connector (1) with a circular groove (5) and a female connector comprising a body (2), a cap (3) and a sleeve (4). The cap (3) hangs from the bottom end of body 2 within which it is able to partly slide. The cap has a bearing surface (7) bearing on the male connector (1) and its bottom part (9) covers the male connector. This bottom part is provided with a circular series of openings (10) each equipped with a finger (11) operable to slide radially. These fingers cooperate with windows (27) in a conical wall (26) of the sleeve (4). Connection is made by gravity, by body 2 pushing down on sleeve 4, which slides downward causing the fingers (11) to slide radially inward. Disconnection is accomplished by sending oil pressure through purposely provided channels (35, 33, 30) into a chamber (20), causing the sleeve (4) to slide up and the fingers (11) to retract.