I. LITERATURE REVIEW OF OFFSHORE OIL AND GAS DRILLING
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These platforms are used in waters not exceeding 200 meters in depth because their cost would
therefore become prohibitive but have the advantage of being able to be ballasted in order to be
moved to another deposit.
The centre of the concrete structure is hollow in order to store oil or water, thereby reinforcing
the stability of the structure.
- Flexible platforms:
Called compliant tower or articulated platforms, this type of platform makes it possible to exploit
the seabed to a depth of about 1000 meters in difficult conditions, the floating bridges are
secured to the bottom by a mechanical hinge, a set of permanently tensioned pipes or by cables
anchored to the seafloor.
- Mobile oil platforms: These platforms are characterized by the possibility of being moved
according to the deposits to be exploited, we find self-elevating and semi-submersible platforms.
- Self- elevating platforms: These platforms are built for oil operations in shallow water
(about 100 meters deep), consist of pillars resting on the seafloor and a hull that can be lifted or
lowered by flotation as required by the site on which they are located, primarily used for drilling
or exploration platforms not equipped with drilling equipment. They can also serve as a place of
life for workers at sea.
- Semi-submersible platforms: These oil platforms allow drilling and oil exploitation to a depth
of up to 1000 meters, can be towed or self-propelled with pods orientable. They are connected to
the seabed by anchors or cables then ballasted in order to immerse them under twenty meters of
water. An upper part of the water ensures the operation. This type of platform thus minimizes
wave movements and thus adapts more easily to difficult seas.
The various oil platforms mentioned above do not allow exploitation in ultra-deep water but still
remain very used since exploitation of shallow water deposits (discovered for the first time by
the technologies developed at the time) may continue for several decades.
The following figure shows the different platforms cited (Fig. 7).
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These platforms are used in waters not exceeding 200 meters in depth because their cost would
therefore become prohibitive but have the advantage of being able to be ballasted in order to be
moved to another deposit.
The centre of the concrete structure is hollow in order to store oil or water, thereby reinforcing
the stability of the structure.
- Flexible platforms:
Called compliant tower or articulated platforms, this type of platform makes it possible to exploit
the seabed to a depth of about 1000 meters in difficult conditions, the floating bridges are
secured to the bottom by a mechanical hinge, a set of permanently tensioned pipes or by cables
anchored to the seafloor.
- Mobile oil platforms: These platforms are characterized by the possibility of being moved
according to the deposits to be exploited, we find self-elevating and semi-submersible platforms.
- Self- elevating platforms: These platforms are built for oil operations in shallow water
(about 100 meters deep), consist of pillars resting on the seafloor and a hull that can be lifted or
lowered by flotation as required by the site on which they are located, primarily used for drilling
or exploration platforms not equipped with drilling equipment. They can also serve as a place of
life for workers at sea.
- Semi-submersible platforms: These oil platforms allow drilling and oil exploitation to a depth
of up to 1000 meters, can be towed or self-propelled with pods orientable. They are connected to
the seabed by anchors or cables then ballasted in order to immerse them under twenty meters of
water. An upper part of the water ensures the operation. This type of platform thus minimizes
wave movements and thus adapts more easily to difficult seas.
The various oil platforms mentioned above do not allow exploitation in ultra-deep water but still
remain very used since exploitation of shallow water deposits (discovered for the first time by
the technologies developed at the time) may continue for several decades.
The following figure shows the different platforms cited (Fig. 7).