Methods and systems are for transferring fluid cargo between a first vessel and a second vessel at open sea in a Parallel configuration. The first vessel is equipped with a cargo connection point and the second vessel is equipped with cargo manifold. A tubular line is connectable between the cargo connection point and the cargo manifold. The method can include attaching a self-propelled buoy to the second vessel; connecting a cargo connection between the self-propelled buoy and the cargo manifold; connecting a cargo line between the cargo connection point and the self-propelled buoy; transferring cargo between the cargo connection point and the cargo vessel; and relying on the self-propelled buoy to keep the self-propelled buoy within predetermined distance boundaries from the first vessel also when the self-propelled buoy is attached to the second vessel.

An example is directed to a mooring apparatus for mooring a vessel via a mooring buoy to an anchor under weather conditions from a light weather condition up to a preset maximum weather condition. A single-bouncer mooring apparatus includes a bouncer connected via an anchor line to the anchor having an anchor weight, the bouncer having a bouncer weight; and a catenary section line connected between the mooring buoy and the bouncer, the catenary section line having a catenary section length and a catenary section weight. The bouncer weight, the catenary section length, and the catenary section weight are selected to place the bouncer just touching the bottom of the body of water in the preset maximum weather condition for the vessel having the vessel length and the vessel weight. A multiple-bouncer mooring apparatus includes two or more bouncers connected in series via respective catenary section lines to the mooring buoy.

System for mooring a large vessel for production of hydrocarbons, such vessel for example being a FPSO vessel, the mooring system comprising at least two floating bodies of the hang-off type, moored by means of differentiated compliance spread anchoring system to the sea bed, allowing partly weathervaning of the large vessel; a riser system extending from the sea bed to each the floating bodies, and means for transfer of fluids from the two floating bodies to the large vessel, the floating bodies and the large vessel being provided with locking means, locking floating bodies to the large vessel at the bow and the stern of the vessel in a mechanically rigid manner, thus providing a integrated, rigidly fixed unit comprising the large vessel and the floating bodies.

A mooring apparatus using a submerged pontoon that does not interfere with floaters and sailing vessels, is not affected by oceanic weather conditions by being submerged at a constant depth, easily separates the floater such as FPSO from the submerged pontoon, in order to cope with an emergency such as stormy weather and avoids collision, and, upon the emergency being terminated, enables the floater such as FPSO to return to the operation area and moor to the submerged pontoon and start the operation. An apparatus for mooring a floater using a submerged pontoon including a submerged pontoon that is placed and fixed at a constant depth below the bottom of the floater, wherein the submerged pontoon is fabricated with buoyant pipes, assumes a planar polygon, is lashed by ropes that are connected to weights or anchors on the seabed and is lashed by ropes that are connected to the floater.

A disconnectable mooring system for offshore semi-submersible floating structures. A disconnectable buoy has a number of mooring lines which include a buoy chain between the mooring chain and the buoy. The mooring chain and the buoy chain are connected via a three way mooring connector, with the third connection configured to pull the mooring connector to a mooring point on the structure. In a first configuration the buoy is disconnected and supports the mooring chains for recovery at shallow depths to be pulled in. In a second configuration, the mooring lines are pulled in via the mooring connectors thereby providing a spread mooring to the structure with the buoy chain left as a catenary between the buoy and mooring point.

Anchoring system having a floating platform from which first anchoring lines emerge, an anchoring block with at least three non-aligned anchoring points, a central float swinging arms being joined by a joint to the block, the joint located in an intermediate area so that each arm has an internal section and an external section, the internal section located between the intermediate area and an inner free end, and the outer section located between the intermediate area and an outer free end, the inner end closer to the central float than the outer end, so that first anchoring lines leaving the floating platform are joined to the outer free ends. The system has second anchoring lines between the central float and the inner end portions containing the inner free ends of the inner sections of the arms. Also a method of install and uninstalling such a system.

A disconnectable mooring system for offshore semi-submersible floating structures. A disconnectable buoy has a number of mooring lines which include a buoy chain between the mooring chain and the buoy. The mooring chain and the buoy chain are connected via a three way mooring connector, with the third connection configured to pull the mooring connector to a mooring point on the structure. In a first configuration the buoy is disconnected and supports the mooring chains for recovery at shallow depths to be pulled in. In a second configuration, the mooring lines are pulled in via the mooring connectors thereby providing a spread mooring to the structure with the buoy chain left as a catenary between the buoy and mooring point.