Abstract: An overload prevention apparatus for a jacking system of a rack and pinion type for use in offshore structures is disclosed. Each of the pinions is provided with a torque meter and tachometer for detecting a relative position between the pinion and the rack. The information detected by the torque meter and the tachometer are respectively fed to a computer the output of which is supplied to an adjust unit for equalizing the load on the jacking system.

Abstract: A mooring system for a tanker comprising an outrigger secured to the tanker, a buoy anchored by chains, and a buoy supporting structure mounted in the outrigger, the buoy supporting structure being connected to or disconnected from the buoy.

Abstract: A device for locking the vertical position of a leg relative to an off-shore work platform having a vertical rack with angular teeth and a lock body with mating angular teeth. The lock body is positioned between a pair of upper and lower wedge members adapted to slidably engage a horizontal face on one side and an inclined face on the other side. The inclined faces of the upper and lower blocks are in opposed directions parallel to the pressure faces of the teeth of the rack and block body. The wedge blocks are adapted to be displaced horizontally in coordination so that when moved simultaneously, a horizontal displacement of the lock body occurs, and when one is moved without the other, an angular displacement of the lock body parallel to the pressure surface of the meshing teeth of the rack is obtained.

Abstract: A method for handling an underwater wellhead assembly by means of an offshore jack-up drilling rig or platform wherein the wellhead assembly is prepared on the shore or quay and is carried on the drilling rig to a preselected drilling location and lowered down therefrom to the ocean floor.

Abstract: An oil fence arrangement for effectively preventing oil spills from spreading or diffusing over the surface of the sea. The arrangement is of a double wall construction and can fold into a small space.

Abstract: A ship for collecting oil from oil spills floating on the surface of the sea comprising a pair of side hulls forming between them a flow passage through which a stream of oil-laden water will flow when the ship travels through the floating oil on the sea. Between the side hulls, a center hull is provided in which a well is formed having a bottom which opens into the flow passage and through which the oil in the passage may float upwardly to be trapped in the well. A pump is provided to pump the trapped oil from the well. The bottom of the well is below the surface of the sea and the stream is deflected under the bottom by a forwardly-inclined segment extending between the side hulls. A splash plate is provided to overlie the upper end of the segment to direct the upward splashes from the segment over the top edge of the segment into a splash chamber behind the segment. The water and/or oil collected in the splash chamber may flow into the well through a communicating opening.