A suction anchor for a subsea well is provided. The suction anchor includes a wellhead support structure. The wellhead support structure is at least in part external of the internal volume of the suction anchor.

A suction anchor for a subsea well is provided. The suction anchor includes a wellhead support structure. The wellhead support structure is at least in part external of the internal volume of the suction anchor.

A subsea fluids storage facility comprises a tank for holding and separating fluids which is equipped with ballast capacity and a separable base to be deployed upon the seabed in shallow or deep water, and the storage facility is connectable to a surface production facility, especially a buoy for processing fluids. In deep water the tank is held at a depth above the base for temperature controlled stabilization of produced oil in the tank.

A subsea fluids storage facility comprises a tank for holding and separating fluids which is equipped with ballast capacity and a separable base to be deployed upon the seabed in shallow or deep water, and the storage facility is connectable to a surface production facility, especially a buoy for processing fluids. In deep water the tank is held at a depth above the base for temperature controlled stabilization of produced oil in the tank.

The present invention relates in some embodiments to a bottom supported drilling unit having two drilling stations for independently drilling (or otherwise working on) two wells simultaneously from a cantilever.

The offshore jack-up has a hull and a plurality of moveable legs engageable with the seafloor. The offshore jack-up is arranged to move the legs with respect to the hull to position the hull out of the water. The method comprises moving at least a portion of a vessel underneath the hull of the offshore jack-up or within a cut-out of the hull when the hull is positioned out of the water and the legs engage the seafloor. A stabilizing mechanism mounted on the jack-up is engaged against the vessel. The stabilizing mechanism is pushed down on the vessel to increase the buoyant force acting on the vessel.

A foundation for a subsea assembly is provided. The foundation includes connection points. The connection points permit other components to be connected to the foundation and permit loads to transfer from the other components into the foundation. The foundation may be a suction anchor. A method of converting an exploration well using the foundation to a production well is also provided.

The invention discloses an offshore Tension Anode system and an installation method thereof. The system comprises a tension platform, a tension device, a composite cable integrated with auxiliary anodes and reference electrodes, and a gravity type foundation base, wherein the tension device is installed on the tension platform; the upper end of the composite cable is tensioned by the tension device, and the lower end of the composite cable sinks to a seabed along with the gravity type foundation base and is anchored by the gravity type foundation base; and the composite cable integrated with the auxiliary anodes and the reference electrodes is a main part of the system. The system is simple in structure and convenient to install and transport. The invention further discloses the installation method of the system, which can safely and reliably install the offshore tension anode system on an offshore platform. The installation method mainly comprises: (1) lifting the composite cable and the gravity type foundation base to an offshore platform; (2) installing the gravity type foundation base on a seabed; (3) installing the composite cable; (4) tension adjustment and lock fixation of composite cable.

An apparatus for use in marine platform jacking is disclosed herein. In one aspect, a jetting valve includes a valve body with a piston assembly disposed therein. The piston assembly is selectively operated to open and close the valve. A biasing member is coupled to the piston assembly. The piston assembly includes a first piston and a second piston. The dual pistons, in cooperation with the biasing member, allow the valve to self-seal thereby preventing entry of a fluid which is external to the valve.

A method of installing an upright elongate hollow subsea foundation that is higher than it is wide, such as a suction pile. The foundation is at least partially embedded in seabed soil. A partition layer is placed within the foundation, for example by injecting a grout, supported by a plug of soil that is surrounded by the foundation. The partition layer is placed on the plug of soil at a level that is spaced from the top of the foundation by at least 20% of the height of the foundation. Above the partition layer, the interior of the foundation may be filled with water and/or a rigid body, such as a solid mass or a hollow liquid-filled tank.