Semi-submersible

The terms semisubmersible, semi-submersible, semi- submersible vessel, semi submersible and semi-submersible boat to be used for various maritime objects. It is either ships that can sink by flooding ballast tanks so that the loading surface comes to lie under water and can accommodate floating goods, or to ships and platforms, which are designed so that the largest part of the float well below the waterline. Even drug submarines that are designed so that the surface vessel is very small and therefore not to be seen as possible, or used as a tourist boats with large portholes below the waterline for observation of fish and coral are called semi-submersible.

Semi-submersible vessels with cargo area

Semi-submersible vessels with cargo area used for the transportation of floating solids. You can regulate their depth by flooding and emptying of floats and thereby set the loading area so under water that floating loads can be added or deleted. These semi-submersible vessels are primarily used as heavy-duty vessels for the transport of other ships, oil rigs, submarines or heavy. Among the largest and most powerful in relation to the transport capacity of semi-submersible vessels include the Dockwise Vanguard, with a capacity of up to 110,000 tonnes and the Blue Marlin, all the oil platforms with a weight of nearly 60,000 tons can carry.

Semi-submersible with floats far below the water surface

Semi-submersible with floats are far below the water surface due to their construction even when the waves are calm in the water and lead, compared with normal vessels, small rolling movements. These properties are achieved by the majority of the float is very far below the surface and is connected to a construction of small cross-section with the surface vessel. Often a catamaran -like structure is chosen with two cylindrical floats. Because the present on the water surface undulations strongly decrease already at shallow depths, thus the buoyant body is exposed to a quieter lake than when it is close to the water surface like a classic ship. The stability of the floating object is thus less affected by the surface currents and the waves from a conventional hull.

This semi-submersible principle is used both for stationary structures such as work platforms and drilling rigs as well as ships. Likewise, deepwater service vessels, which are used for the construction of offshore structures, often designed as semi-submersible.

A further application of this principle is the small- waterplane -area twin -hull ship ( SWATH ). These ships are similarly designed as a twin-hulled boat catamaran. The waterplane area is kept as small as possible, which means that the floats are far below the water surface.

Semi-submersible as drugs submarine

Semi-submersibles are used for the smuggling of drugs from Central America to Mexico. Her hull is generally constructed of fiberglass and is driven by a diesel engine. You go just below the water surface and can therefore be from another ship look bad, but are out of the air relatively easy to discover.

Semi-submersibles for fish observation

In tourism semisubmersible be used for observation of fish and coral. These boats are provided at the bottom with large portholes, which allow passengers easy observation of marine life without diving or snorkeling equipment.