TLP) Is an Offshore Floating Platform Which Is Used for Oil and Gas Exploration
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[3164] A Tension Leg Platform (TLP) is an offshore floating platform which is used for oil and gas exploration. The Tension Leg Platform (TLP Platform) is so referred because of its structural dynamics. The offshore platform consists of steeled sinewy pillars that are tautened on purpose and supported with cable-lines to provide weightlessness to the floating operational platform structure above the surface of the water. One of the most extensively used type of oil platform, the oil platform design gains immense credibility primarily because of this structural singularity and secondly because of its high efficiency levels in comparatively deeper high seas operational areas. [3165] The constructional configuration of the TLP platform can be categorized into three major components. The operational rectangular deck of the platform rising above the oceanic surface is quite akin to other types of high seas’ drilling and rig decks. Just below the operational platform are four pontoon-like pillars filled up with air that provide the necessary weightlessness to the above placed operating deck. These pontoon-like structures are regarded to be the mainframe torso of the entire tension leg platform. [3166] Affixed to this torso are the cable-lines that are appropriately tautened so as provide the necessary tenseness that would account for the weightlessness of the overall structure. Extending from the pontoons are the steeled sinews, founded deep into the oceanic depths. These steeled structures enable the provision of stability to the entirety of the offshore oil drilling platform on a more permanent basis, as compared to other existing offshore rig platforms. [3167] The structural paradigm of this type of oil platform prevents disruptions to the drilling operations arising on account of instability of the structure’s foundation. Thus while the tension leg platform is subject to slight sideways motions at its surface because of the tidal motions, the continuity of the drilling operations are well-accounted for because of the stability of the structure at its constructional base. [3168] These kinds of oil platforms are highly suitable in areas prone to regular volatility of the oceanic conditions. Examples of some of the high seas where TLP platforms are currently operated include the Gulf of Mexico and in certain parts of the North Sea. [3169] Alongside being utilized for excavation of oil from their sub-water reservoirs, these platforms have also been recommended to be utilized for the purposes of installing wind turbines in the high seas. The TLP platforms provide a high costto-benefit ratio and their installing in the required oceanic zone is carried out part-by-part by assembling the various components of the platforms. [3170] These ingenious drilling instrumentations have been in operational existence since the latter part of the 20th century. In the course of the three decades since their pioneering, several advancements have been made to their initial engineering concept which had further catapulted the utility value of these engineering marvels while presenting the marine domain with yet another viable alternative to carry out the necessary maritime activities. [3171] Ocean Thermal Energy Conversion (OTEC) Power Plant. When operational, the power plant will be able to generate up to at least 10 megawatts of energy, enough to sustain the energy requirements of a smaller metropolis. high seas were specifically chosen as a preferred location for the power plant. The warmness of the oceanic water in the tropics accounts for a greater degree of variation between the surface and sub-water temperatures which results in great enhanced work ability for the power plant. In addition to its comparatively higher energy generating capacity, the proposed OTEC power plant will also offer the following benefits: Consistent and round-the-clock production of energy without any stoppages or interruptions. Substantial reduction in the emanating of noxious gases. Substantial reduction in conventional fuel consumption costs. [3172] The energy generated through the power plant can also be transferable to other areas like desalination of water resources and providing fuel to electricity-driven automobiles. The OTEC power plant nevertheless promises to bring in significant yields. The OTEC Power Plant: Operational System. 1). Consisting of turbine systems placed above the surface of the water, the OTEC power plant will primarily involve boiling a liquid by channelizing the warm surface waters of the ocean. 2). The liquid utilized will be one having a comparative lower boiling point so as to offset faster boiling. 3). The next step would involve an equally rapid cooling of the thus boiled liquid passed through pipes to the under-water turbine systems positioned underwater. 4). Energy would be generated by this constant process of the fluid being boiled and cooled. [3173] The utilization of OTEC power plants has been considered as an alternative fuel generation system since the late 20th century wherein the cycle consists of cold sea seawater circulating through heat exchange evaporator motor for warm seawater and condenser motor of cold seawater providing the working fluid pumped through the turbine rotor which drives the coupled generator having a rotating magnetic field and matrix of coil wiring in several faces generating a pulsing electric current. the condenser. [3174] Types of offshore rigs: 1.1 Barges. 1.2 Submersibles. 1.3 Platforms. 1.4 Jackups. 1.5 Floaters. 1.6 Semisubmersibles. 1.7 Drill ships. [3175] Barges: A barge rig is designed to work in shallow water (less than 20 ft deep). The rig is floated to the drill site, and the lower hull is sunk to rest on the sea bottom. The large surface area of the lower hull keeps the rig from sinking into the soft mud and provides a stable drilling platform. [3176] A submersible rig is a barge that is designed to work in deeper water (to 50 ft deep). It has extensions that allow it to raise its upper hull above the water level. [3177] Platforms use a jacket (a steel tubular framework anchored to the ocean bottom) to support the surface production equipment, living quarters, and drilling rig (Figure 1). Multiple directional wells are drilled from the platform by using a rig with a movable substructure. The rig is positioned over preset wellheads by jacking across on skid beams. After all the wells are drilled, the rig and quarters are removed from the platform. Smaller platforms use a jack-up rig to drill the wells. Jack-ups [3178] Jackups are like platforms except that the support legs are not permanently attached to the seafloor (Figure 2). The weight of the rig is sufficient to keep it on location. The rig's legs can be jacked down to drill and jacked up to move to a new location. When under tow, a flotation hull buoys the jackup. The derrick is cantilevered over the rear to fit over preset risers if necessary. [3171] Floaters: Offshore rigs that are not attached to or resting on the ocean bottom are called floaters. These rigs can drill in water depths deeper than jackups or platforms can. They have several special features to facilitate this: They are held on location by anchors or dynamic positioning. The drill string and riser are isolated from wave motion by motion compensators. The wellheads and BOPs are on the ocean bottom and are connected to the rig by a riser to allow circulation of drilling mud. There are two categories of floaters: semisubmersibles and drill ships. [3172] Semisubmersibles (also called semis) are usually anchored in place (Figure 3). Although a few semis are self-propelled, most require towing. Because floaters are subject to wave motion, their drilling apparatus is located in the center where wave motion is minimal. Semis are flooded to a drilling draft where the lower pontoons are below the active wave base, thereby stabilizing the motion. [3173] Drill ships: The drilling apparatus on a drill ship is mounted in the center of the ship over a moon pool, which is a reinforced hole in the bottom of the ship through which the drill string is raised and lowered). The ship can be turned into the oncoming wind or currents for better stability, and it can operate in water too deep for anchors. [3174] The inventions include Jackup vessel for offshore installation of wind turbines, consisting of self- elevating, self-propelled jack-up vessels and crew transfer vessels. With a large open deck and wrap-around- the-leg cranes, our jack-up vessels Brave Tern and Bold Tern are among the most versatile and efficient installation vessels in the offshore wind industry. Specifically designed to withstand harsh offshore conditions and is capable of operating throughout the year in water depths of up to 65 meters deep or more. The vessels have 800-tonne wrap-around-the-leg offshore-rated cranes, designed by Gusto MSC, as well as robust, continuous-type hydraulic jacking systems. In addition, each vessel has a DP2-class type dynamic positioning system and is fitted with a Voith Schneider propulsion system enabling secure and accurate positioning capabilities. Brave Tern and Bold Tern feature high-quality accommodation for up to 80 people in 56 cabins and have helidecks for transfers during offshore operations. Marine operations. [3174] Specification regarding the Jackup vessel. Class: DNV +1A1 HSLC R2 Windfarm Service 1 Passengers: 12 (16) Crew: 2 Range: 775nm (max. 100nm from shore) Hull: Aluminium Length o.a.: 20.9m (excl bow fender) Beam: 7.0 m Max draught: 2.1m Bunker capacity: 8000 litres Fresh water capacity: 800 litres Deadweight: 20 t Total forward deck capacity: 51m2 Forward deck dimensions: 6x8.5m Soft impact fender system Danish flagged Propulsion: 2 x CPP [3175] Cargo Handling Max cargo capacity on deck: 8t Deck strength: 2 t/m2 Reinforced loading area: 27 m2 Max lifting capacity: 3000kg Max lifting capacity at max outreach: [email protected] [3176] Passenger Facilities.