Abstract: A carrier adapted to move between a movable vessel, such as a boat, and a stationary platform. The carrier has an extendable and retractable intermediate uphaul line adapted to be connected to a crane on the platform. It also has a downhaul line connected between the carrier and the vessel. When the carrier is being lifted from the vessel, the downhaul line is payed out at a controlled rate with the uphaul line extending and retracting to keep the carrier out of contact with the vessel which may be rising or falling due to wave action of the water. At a predetermined elevation, the tension in the downhaul line is decreased so that the uphaul line retracts to move the carrier out of the area of possible contact with the vessel. The reverse operation is followed to move the carrier from the platform to the vessel.

Abstract: Polymetallic nodules are collected by means of a plurality of self-propelled vehicles which move upwards and downwards between the sea floor and a surface platform under the action of excess ballast which is partially and progressively released as the vehicle approaches the bottom. The vehicles are propelled along the sea floor by means of at least two supporting units each having at least one helical propulsion fin, the remainder of the ballast being released in order to return the vehicles upwards for docking, unloading and energy-recharging in the surface platform.

Abstract: A ship or other vessel having a moonpool therein and an enclosed space above the moonpool is provided with a pontoon which floats on the surface of the sea within the moonpool. The effects of the enclosed space is that said sea surface is calm even when the ambient sea is subject to an adverse swell, and the effect of the pontoon is that it will remain substantially stationary and be independant of the vessels heaving motion, i.e. the pontoon is de-coupled from the vessel. Lifting gear mounted on the pontoon is used to lower and raise submersibles, sub-sea equipment, tethered bells or divers (tethered or free swimming). The pontoon may be used as a stable work area and for loading and unloading cargo; in the latter case, a housing forming the enclosed space above the moonpool has a double opening through which the cargo can pass, but only on opening at a time is opened so as to preserve the enclosed space above the moonpool.

Abstract: Diving bell launch tube has a vertical passageway having a surrounding surge chamber adjacent to the water surface. The surge chamber communicates with the passageway through perforations and the holes of the perforated section are tuned with respect to the surge chamber volumes to achieve damping of water oscillation in the tube.

Abstract: A handling system for lowering and lifting a diving bell between the ocean surface and the deck of a vessel or a marine platform includes a horizontally extendible and retractable frame which mounts sheaves used for directing the hoist cable and umbilical cable into communication with the bell. The frame comprises a pair of elongate beams driven by means of a pair of hydraulic motors having pinions which engage racks built integral with the beams. The frame includes a member having a downwardly opening frusto-conical inner surface which is adapted to mate with a similar frusto-conical superstructure on the diving bell. A plurality of locking fingers are operatively arranged on the upper frusto-conical member for automatically locking the superstructure to the frame in a stabilized position over the water.

Abstract: A method of establishing a ship loading or unloading pier facility comprises providing a buoyant self-propelled vessel having removable jack-up legs and a well carrying a plurality of buoyant jack-up platforms, propelling the vessel with the legs stored on deck to an off-shore site adjacent a shore line, floating the platforms out of the vessel through an opening in the hull thereof, jacking-up the vessel to render it stationary, and arranging the platforms together with connecting tressels to form a roadway between the vessel and to shore. The vessel carries a crane which is used to remove and install the jack-up legs and to transport cargo between a cargo ship moored to the vessel and the roadway.

Abstract: A gantry crane and gantry crane reeving are provided having two pairs of drums on each side of said gantry, an upper sheave assembly on the gantry above each drum, each drum having a pair of independent cables reeving from the drum to said upper sheave assembly above it on the gantry, a lower relatively movable sheave assembly below each upper sheave assembly, one cable from each pair of cables passing over one sheave of the upper sheave assembly and downward around the lower sheave assembly and back over the upper sheave assembly and dead ending at the lower sheave assembly, the other cable from each pair of cables passing over a sheave of the upper sheave assembly across the gantry to the opposite upper sheave assembly on the other side of said gantry and downwardly to the lower sheave assembly on said other side and back over the said opposite upper sheave assembly and dead ending at the said opposite lower sheave assembly.