Technical domain of the invention
[0001] The present invention relates to the support structure of semi-submersible floating
platforms designed to marine environments. The invention is related to the structure
of this type, semi-submersible platform that has hydraulics support structure placed
in the bottom that allows you to switch between static and floating positions, gathering
and stretching the same, ensuring the stability of vertical and horizontal.
Prior Art
[0002] There are in use several types of offshore platforms that are classified according
to their support structure. These platforms are classified as fixed or floating. Fixed
platforms are platforms on which the support structure is founded on the sea floor
by gravity or truss towers. The floating platforms are structures where the flat operative
platform is situated above the water line, and this is connected by supporting columns
to the lower structure.
[0003] The semi-submersible floating platforms fall on the floating structures mentioned.
The platform submerged function in the marine environment is achieved by filling the
tanks located in the lower support structure and columns of connection between the
flat operative platform and support structure. This support structure and lower the
columns that connect the flat operative platform are rigid and fixed, and its position
secured through dynamic positioning systems.
[0004] These structures have a high stability allowing a very stable horizontal float.
Description of figures
[0005] Fig. 1 - Figure 1 shows a perspective view of the invention, i.e., the semi-submersible
floating in its static position or elongated.
[0006] The invention, as illustrated in Figure 1, consists of a rigid flat operative platform
(4), supported by a semi-submersible lower support structure that consists of four
main columns (1) that work with hydraulics that allow switching between a position
more elongated and static and a reduced and floating position.
[0007] The lower support structure comprises a vertical truss structure (3) and horizontal
(2). The vertical truss structure (3) is equipped with hydraulics that allows monitoring
of the stretching or recoiling movements of main columns (1). At the bottom of the
four main columns (1) are four circular flooding tanks (8). Under the rigid flat operative
platform (4) are two floating keels (5).
[0008] Fig. 2 - Figure 2 shows a perspective view of the invention, i.e., the semi-submersible
floating in its floating position or recoiled.
[0009] The invention, as illustrated in Figure 2, consists of a rigid flat operative platform
(4), supported by a semi-submersible support structure that consists of four main
columns (1) that work with hydraulics that allow switching between a position more
elongated and static and a reduced and floating position.
[0010] The lower support structure comprises a vertical truss structure (3) and horizontal
(2). The vertical truss structure (3) is equipped with hydraulics that allows monitoring
of the stretching or recoiling movements of main columns (1). At the bottom of the
four main columns (1) are four circular flooding tanks (8).Under the rigid flat operative
platform (4) are two floating keels (5) and an anti-wave support structure (6), composed
of tubular metal elements, which is connected to the horizontal truss structure (2)
and to the rigid flat operative platform (4).
[0011] Fig. 3 - Figure 3 shows a perspective view of the invention, i.e., the semi-submersible
floating in its floating position or recoiled.
[0012] The invention, as illustrated in Figure 3, consists of a rigid flat operative platform
(4), supported by a semi-submersible support structure that consists of four main
columns (1) that work with hydraulics that allow switching between the position more
elongated and static and a reduced and floating position.
[0013] Under the rigid flat operative platform (4), according to Figure 3, there are two
floating keels (5). The invention has under the platform, an anti-wave protection
structure (7) like a "blind", which protects the bottom of the submersible platform
structure and is linked to this through an anti-wave support structure (6), composed
of tubular metal elements.
[0014] Fig. 4 - Figure 4 shows a plan view from the top of the invention, i.e., the semi-submersible
floating.
[0015] The invention, as illustrated in Figure 4, consists of a rigid flat operative platform
(4) with a square geometry.
[0016] Fig. 5- Figure 5 shows a plan view of the bottom of the invention, i.e., the semi-submersible
floating in your static position or elongated.
[0017] The invention, as illustrated in Figure 5, consists of a rigid flat operative platform
(4), supported by a semi-submersible support structure that consists of four main
columns (1) that work with hydraulics that allow switching between the position more
elongated and static and a reduced and floating position.
[0018] The lower support structure comprises a vertical truss structure (3) and horizontal
(2). The vertical truss structure (3) is equipped with hydraulics that allows monitoring
of the stretching or recoiling movements of main columns (1). Under the rigid flat
operative platform of operation (4) are two floating keels (5). At the bottom of the
main columns (1) are four circular flooding tanks (8).
Detailed description of the invention
[0019] The invention is a structure of semi-submersible floating platforms where the lower
support structure, that is placed under the rigid flat operative platform is equipped
with hydraulics that allows stretching or recoiling of this structure, which allows
the semi-submersible platforms alternate between a static or stretched position and
a recoiled position or floating. Additionally, the system includes a mobile anti-waves
structure and a self-propulsion system of that will be used when the platform is in
the recoiled position or floating.
[0020] The execution of the structure of semi-submersible floating platforms requires the
consideration of the necessary requirements of buoyancy, positioning, stability, mobility
and functionality. The requirements listed come from the fact that the function of
the structure couldn't interfere with the security required and mandatory to structures
in marine environments, since this structure can, for example, be used in partnership
or in help to other structures that are located in the marine environments.
[0021] The structure of semi-submersible floating platform comprises a flat rigid operative
platform, that is above the waterline, two floating keels in the bottom of the flat
operative platform and a lower support structure which is composed of four main columns,
four circular flooding tanks, a vertical and horizontal truss structure, an anti-waves
structure and its supporting structure, as illustrated in Figures 1 and 3.
[0022] The rigid flat operative platform, as the name implies, is a flat and rigid structure
that lies above the waterline of the marine environment where the structure is.
[0023] The platform provides physical support to the machinery and devices necessary for
its operation, providing in its interior, space and area for its installation. That
platform has, at its top, area for installation and operation of services whose diversity
depends on the desired operation for the entire structure.
[0024] The floating keels are located under the rigid flat operative platform and they give
support and buoyancy to the structure of semi-submersible platform when the lower
support structure is fully recoiled. Thus, the structure will float on the floating
keels in a process similar to a vessel, which they must be properly sealed.
[0025] The lower support structure is located under the rigid flat operative platform and
its position is in an area between the two floating keels above mentioned. The main
columns belonging to the lower support structure connect the platform to the rigid
flat operative platform to the four circular flooding tanks located at the end of
the main columns. These columns consist of hydraulic mechanisms that allow switching
between a more elongated or recoiled position of the columns, according to the operation
of a hydraulic cylinder. When the main columns are in its most elongated position,
they guarantee structural stability of the entire platform.
[0026] The main columns are connected by a vertical truss structure and a horizontal truss
structure. The vertical truss structure connects the vertical columns to the rigid
flat operative platform. These have hydraulics that allows them to track the movement
of recoiling or lengthening of the main columns. When the main columns are in its
most elongated position, the vertical truss structure is also at its most elongated
position, ensuring structural stability of the main columns even if they are subject
to side effects of existing currents in the marine environment.
[0027] The horizontal truss structure, which connects the circular flooding tanks on the
main columns, is a fixed and rigid structure, which tracks the movement of recoiling
or stretching of the main columns and the vertical truss structure without changing
its extension, since it is rigid. This structure ensures the verticality of the main
columns, providing structural rigidity and strength when they are subject to action
from the side effects caused by the chains present in marine environments.
[0028] When the columns are in their recoiled position, the structure of semi-submersible
platform is in its floating position. At this stage, the main columns and the vertical
truss structure is completely recoiled and near the bottom of the rigid flat operative
platform. In the horizontal truss structure, is a support structure consisting of
several metal tubular elements. These metallic elements connected to the tubular truss
structure are the horizontal anti-wave support structure. The front and rear parts
are supported by a structure comprised of tubular metal elements that are connected
to the flat platform of operation for its rigid bottom.
[0029] The anti-wave protection is a structure that protects the whole lower structure of
the semi-submersible platform. This anti-wave protection will only be used when the
semi-submersible platform is in it's more recoiled or floating position. The anti-wave
protection is composed of laminar rectangular elements that are connected to the horizontal
truss structure by metal tubular elements protruding from underneath structure. The
laminar rectangular elements which are linked by their support structure to the horizontal
truss structure, perform a rotation of 90° around a central axis, located along the
axis of those laminar rectangular elements, making a motion similar to a "blind".
When the platform is in its more elongated position, the laminar rectangular elements
have a vertical position which helps to stabilize the platform, functioning as rudders.
When the platform is in it's most recoiled or floating position, laminar rectangular
elements rotate around the axis, in sequence, assuming a horizontal position making
a perfect fit between the laminar elements, constituting the flat part of the anti-wave
structure of the bottom of the semi-submersible platform.
[0030] The front and rear parts of the anti-wave protection are linked to the rigid flat
operative platform through its rigid support structure that performs a rotation movement
around a point, making a motion like "fan" where the laminar elements are arranged
in a movement like "blind".
Description of Method
[0031] The structure of the floating semi-submersible platform ensures buoyancy based on
the Archimedes buoyancy principle, which formulated that when a body is dived in a
liquid, it will shift a proportion of liquid equal to its volume, and the weight of
that liquid volume is subtracted from the weight of the body by the force called impulse.
Thus, the practice of monitoring the depth of such platforms has become possible and
is used quite often.
[0032] The movement of recoiling and extension of the main columns and the vertical truss
structure will be made by means of hydraulic mechanisms, by pressurizing the fluid
contained within the hydraulic mechanisms, performing the stretching of hydraulic
cylinders. The combination of pressurized liquid density inside the hydraulics and
the flooding of the circular flooding tanks at the bottom of the main columns, allows
monitoring of buoyancy and stability of the structure during the recoiling or stretching
of the main columns and the vertical truss structure.
[0033] The lower structure of the semi-submersible floating platform is arranged to ensure
the structural stability of the platform when it is in the most elongated position.
At this stage, in which the semi-submersible platform is in its static position, it
is necessary to ensure horizontal and vertical stability, since the structure is subject
to the effect of existing currents in marine environments.
[0034] The arrangement of the lower structure of the semi-submersible platform was achieved
in order to offer the least resistance to these maritime currents. When completed,
the process of transition from the recoiled or floating position to an elongated or
static position, the semi-submersible floating platform will get the water line of
the marine environment halfway up the main columns, thus minimizing the movements
of the rigid operative platform caused by the excitation of the waves. The stabilization
of the position of semi-submersible floating platform when it is in its most elongated
and static position, is achieved through a system currently in use so-called dynamic
positioning system.
[0035] This system consists of a complex system of sensors that can be GPS, sonar, anemometers,
or other, that measure the position and direction of the platform, sending information
to a central processor responsible for executing the control algorithm. This processor
automatically sends the information to control propellers or rudders which ensure
the platform position. This system is widely used in various ways to navigate in marine
environments. When the semi-submersible floating platform passes from is it's most
elongated and static position to a recoiled or floating position, there is a reversal
of the referred process, gathering the lower support structure of the platform, that
consist of the main columns and the vertical truss structure and horizontal.
[0036] After gathering all the lower support structure, the semi-submersible platform can
be seen floating on the two floating keels that stay under the rigid flat operative
platform. In order to protect the lower support structure of the platform, the anti-waves
protection is activated. The laminar rectangular elements that form the anti-waves
protection are in their upright position and when the entire lower support structure
of the platform is recoiled, they rotate around the axis that lies within. The movement
ends when the rectangular laminar elements are in a horizontal position, making anti-waves
protection platform. On the front and rear parts of this anti-waves protection, multiple
rectangular laminar elements, supported by its supporting structure, will rotate around
the connection point on the rigid flat operative platform.
[0037] In order to make a protection in a circular form, rectangular laminar elements "fall"
of the rigid flat operative platform, disposing the protection elements in a movement
such as "blind".
[0038] The platform gains this way, a new mobility while floating on those floating keels
and self-propelled floating through the effect of suitable propellants.
1. - Support structure of semi-submersible floating platforms, aimed at the marine environment,
with hydraulics placed in the lower support structure that allows switching between
elongated and recoiled positions, is characterized by consisting of a rigid flat operative platform (4), two floating keels (5), four main
columns (1), a vertical truss structure (3), a horizontal truss structure (2), an
anti-wave support structure (6), an anti-wave protection (7) and four circular flooding
tanks (8).
2. - Semi-submersible floating platform with hydraulics and autonomous movement characterized by, according to claim 1, having hydraulics mechanisms in the lower structure of the
platform, to switch between static and most elongated position and a more recoiled
and floating position.
3. - Semi-submersible floating platform with hydraulics and autonomous movement characterized by, according to claim 1, having four circular flooding tanks (8) in the main columns
(1) with hydraulics.
4. - Semi-submersible floating platform with hydraulics and autonomous movement characterized by, according to claim 1, having floating keels (5) self-propelled.
5. - Semi-submersible floating platform with hydraulics and autonomous movement characterized by, according to claim 1, having an horizontal truss structure (2) in the rigid flat
operative platform (4), an anti-wave support structure (6).
6. - Semi-submersible floating platform with hydraulics and autonomous movement characterized by, according to claim 1, having an anti-wave protection (7) under the lower support
structure, which act as a rudder, providing the stability of the platform.
7. - Semi-submersible floating platform with hydraulics and autonomous movement characterized by, according to claim 1, having an anti-wave protection (7) under the rigid flat platform
of operation.