WO2018230252A1

WO2018230252A1 - Ocean floating body structure

Info

Publication number: WO2018230252A1
Application number: PCT/JP2018/019182
Authority: WO
Inventors: 靖弘十川; 浩太朗高野; 沙織岡
Original assignee: 三井Ｅ＆Ｓ造船株式会社
Priority date: 2017-06-15
Filing date: 2018-05-17
Publication date: 2018-12-20
Also published as: JP2019001321A

Abstract

This ocean floating body structure has a buttock flow-type stern 11. An additional structure 20 is provided on the outer wall surface of a bottom plate 15 of the stern 11. The additional structure 20 extends in the vessel longitudinal direction. The width of the addition structure 20 at the front end is at least 50% of the vessel width and decreases toward the rear. The length of the additional structure 20 in the vessel longitudinal direction is 70%-190% of the vessel width.

Description

Offshore floating structure

The present invention relates to offshore floating structures such as floating production storage and loading equipment (FPSO) and floating storage and loading equipment (FSO), and more particularly to improvement of the stern structure of the floating floating structure.

Offshore floating structures such as FPSO and FSO have been required to have a large dead weight, that is, a large amount of drainage, because the required loading and storage amount of cargo oil has increased with the recent discovery of large oil fields. . Therefore, the hull of this type of offshore floating structure has a box shape, and is often formed by fertilizing the stern. On the other hand, offshore floating structures are towed or self-propelled when moving between different yards in the construction process or moving to the installation sea area, but because the stern part is fertile, large resistance occurs during movement, There is a problem that the propulsion performance and the maintenance performance are poor. As a solution to this, as disclosed in Patent Document 1, the buttocks flow type stern part is adopted to reduce the resistance and improve the propulsion performance, and in addition to the center skeg, an auxiliary skeg is provided to maintain the needle. It is conceivable to ensure performance.

JP2011-168251A

However, the configuration disclosed in Patent Document 1 has a buttock flow type stern, so the bottom deck area of the engine room is small, and it is difficult to arrange a pump for pumping seawater, a bilge pump, a sludge pump, and the like. There's a problem.

An object of the present invention is to make it possible to easily arrange a pump such as a pump for pumping seawater in a stern part in an offshore floating structure having a buttocks flow type stern.

The offshore floating structure according to the present invention includes an additional structure provided on the outer wall surface of the bottom plate of the stern, the additional structure extends in the ship length direction, and the width of the additional structure is 50% or more of the ship width at the front end. It is characterized by becoming narrower toward the rear.

It is preferable that the length of the additional structure in the ship length direction is 70% to 190% of the ship width. The outer surface of the additional structure forms, for example, a triangular prism surface having an axis extending in the vertical direction. The front end width of the additional structure may be the same as the ship width. The corner of the lower end of the additional structure may be formed in a round shape over the entire length of the additional structure.

According to the present invention, it is possible to obtain an offshore floating structure in which a pump such as a seawater pump can be easily arranged at the stern.

1 is a side view showing a schematic configuration of a FPSO hull to which first to fourth embodiments of the present invention are applied. FIG. FIG. 2 is a plan view taken along lines XX and YY in FIG. 1 in the first embodiment. FIG. 2 is a cross-sectional view taken along the line ZZ in FIG. 1 in the first embodiment. It is a perspective view which shows the stern part of 1st Embodiment. FIG. 8 is a plan view taken along the line XX and line YY in FIG. 1 in the second embodiment. FIG. 10 is a plan view taken along lines XX and YY in FIG. 1 in the third embodiment. FIG. 10 is a plan view taken along lines XX and YY in FIG. 1 in the fourth embodiment. FIG. 10 is a cross-sectional view taken along line ZZ in FIG. 1 in the fourth embodiment.

Hereinafter, the present invention will be described with reference to the illustrated embodiments.
FIG. 1 is a side view of a FPSO hull 10 to which the first to fourth embodiments of the present invention are applied, and the configuration of the hull 10 is common to the respective embodiments. The stern 11 is a so-called buttocks flow type, and the bottom plate 15 of the stern 11 is raised rearward.

The first embodiment will be described with reference to FIGS. In FIG. 2, the solid line shows the planar shape seen along line XX in FIG. 1, and the broken line shows the planar shape seen along line YY in FIG. 1, but both overlap at the rear end. ing. FIG. 3 is a cross-sectional view taken along line ZZ in FIG. FIG. 4 is a perspective view of the stern portion as viewed obliquely from below. In FIG. 4, imaginary lines S <b> 1 and S <b> 2 are virtual lines indicating the boundary between the stern 11 and the hull parallel portion 13.

The hull 10 is a hull parallel portion 13 having a box shape except for the stern 11 and the bow 12. Both

side walls

14 and 14 of the stern 11 are flat plates parallel to each other, and are on an extension of the side wall 17 of the hull parallel portion 13. The bottom plate 15 also has a flat plate shape and is inclined so as to become higher toward the rear.

An additional structure 20 is provided on the outer wall surface of the bottom plate 15. The additional structure 20 extends in the ship length direction, and the planar shape thereof has a triangular shape that becomes narrower toward the rear (see FIG. 2). The additional structure 20 is basically composed of three flat plates and has a pair of

side plates

21 and 21 and a bottom plate 22. The bottom plate 22 is a flat plate obtained by extending the ship bottom 16 of the hull parallel portion 13. The front ends of the

side plates

21, 21 are located at the boundaries S 1, S 2 with the hull parallel part 13, and the rear ends 23 of the

side plates

21, 21 intersect slightly on the front side with respect to the rear end surface 18 of the stern 11. That is, the outer surface of the additional structure 20 forms a triangular prism surface having an axis extending in the vertical direction.

In the present embodiment, the width Ba of the front end of the additional structure 20 is substantially the same as the ship width B of the hull parallel portion 13, but may be 50% or more of the ship width B. The length La of the additional structure 20 in the ship length direction is 70% to 190% of the ship width B, and more preferably 100% to 150% of the ship width B.

As described above, in the present embodiment, the additional structure 20 whose width decreases toward the rear is provided on the outer wall surface of the bottom plate 15 of the stern 11, and the width Ba of the front end of the bottom of the additional structure 20 is the ship width B. It presents a triangle that is about the same as. That is, the volume of the additional structure 20 is considerably larger than that of a normal skeg, and the area of the bottom is also large. Therefore, a space for arranging a pump such as a pump for pumping seawater can be easily secured on the bottom surface in the additional structure 20. Further, since the side plate 21 of the additional structure 20 is a flat plate extending substantially in the ship length direction, the same effect as that of a normal skeg is obtained with respect to the needle-keeping performance of the hull 10. Further, since the additional structure 20 is configured so that the width becomes narrower toward the rear, the flow of water from the hull parallel portion 13 is smooth, the resistance increase can be suppressed, and the propulsion performance is improved. To do.

As a FPSO construction method, the stern 11 and the bow 12 are manufactured in a first yard, temporarily joined, and moved to a second yard in which the hull parallel part 13 is manufactured. In this manufacturing process, when leaving the dock at the first yard and when entering the dock at the second yard, the stern 11 is sufficient to create a stacked state of the combined body of the stern 11 and the bow 12. It is preferable that there is a buoyancy. In this regard, in the present embodiment, the volume of the additional structure 20 is larger than that of a normal plate-shaped skeg, so that the buoyancy of the stern 11 is increased and dead weight is compared with the conventional configuration in which the plate-shaped skeg is provided. Can be increased.

Further, in the method of manufacturing the stern 11 as a mega block, the stern 11 may be moved within the manufacturing yard, or the stern 11 may be moved from another yard to be combined with the hull portion to complete the hull. is there. Even in such a case, according to this embodiment, since the volume of the additional structure 20 is large, the buoyancy of the stern 11 can be increased, so that the manufacture of the hull is facilitated.

通常 Normal merchant ships have a complicated three-dimensional shape due to propulsion performance, etc. For example, in the manufacture of stern, complicated bending work is required, and the work takes time. In this regard, in the present embodiment, the additional structure 20 has a triangular prism shape, and the pair of

side plates

21 and 21 and the bottom plate 22 are flat plates, so that the work is simple, thereby shortening the construction period of the FPSO. it can.

FIG. 5 shows the stern part of the second embodiment, the solid line shows the planar shape seen along line XX in FIG. 1, and the broken line shows the planar shape seen along line YY in FIG. Show. In the second embodiment, the width Ba at the ship bottom at the front end of the additional structure 20 is narrower than the ship width B of the hull parallel portion 13. That is, the triangle of the bottom plate 22 (see FIG. 3) of the additional structure 20 is longer than the triangle of the bottom plate 22 (see FIG. 3) in the first embodiment, and the rear end 23 which is the apex of the triangle is rounded. . Further, unlike the first embodiment, the side plate 21 has a curved surface shape that spreads outward as it extends upward and increases in width as it approaches the front end. On the other hand, the bottom plate 15 (see FIG. 3) of the stern 11 extends back and forth in a flat plate shape, and at its front end, the connecting portion 19 of the hull parallel portion 13 with the bottom 16 (see FIG. 4) has a predetermined line segment length on both sides. Have

In the second embodiment, the additional structure 20 is formed thinner than in the first embodiment, and the pair of

side plates

21 and 21 are curved in a flare shape. A connecting portion 19 between the bottom plate 15 of the stern 11 and the bottom 16 of the hull parallel portion 13 has a predetermined line segment length on both sides. Therefore, compared with 1st Embodiment, the flow of the water from the ship bottom 16 of the hull parallel part 13 to the baseplate 15 of the stern 11 becomes smoother, resistance increase can be suppressed, and propulsion performance improves. .

FIG. 6 shows the stern part of the third embodiment, the solid line shows the planar shape seen along line XX in FIG. 1, and the broken line shows the planar shape seen along line YY in FIG. As shown, both overlap at the rear end. The difference in configuration between the third embodiment and the first embodiment is that the width Ba of the front end of the additional structure 20 is narrower than the ship width B of the hull parallel portion 13. Other configurations are the same as those of the first embodiment.

According to the third embodiment, since the additional structure 20 is composed only of a flat plate, the manufacture of the stern 11 is significantly simplified as compared with the second embodiment.

7 and 8 show the stern part of the fourth embodiment. In FIG. 7, the solid line shows the planar shape seen along line XX in FIG. 1, and the broken line shows the planar shape seen along line YY in FIG. 1 (however, before the corner 24 is round). Virtual line). FIG. 8 is a cross-sectional view taken along line ZZ in FIG. The configuration of the fourth embodiment is basically the same as that of the first embodiment, but the shape of the lower end of the additional structure 20 is different. That is, in the fourth embodiment, the corner 24 where the side plate 21 and the bottom plate 22 intersect is formed in a round shape over the entire length of the additional structure 20. The round shape of the corner portion 24 is an arc having the same curvature as the round shape of the corner portion where the ship bottom 16 (see FIG. 4) and the side wall 17 (see FIG. 4) in the hull parallel portion 13 intersect. The curved surface shape may be changed so as to smoothly connect to the corner where the ship bottom 16 and the side wall 17 intersect. Other configurations are the same as those of the first embodiment.

According to the fourth embodiment, since the corner 24 at the lower end of the additional structure 20 is formed in a round shape over the entire length, the flow of water around the additional structure 20 becomes smooth, and an increase in resistance is suppressed. Can improve the propulsion performance.

In addition, you may apply the round-shaped corner | angular part 24 of 4th Embodiment to the structure of 2nd Embodiment (FIG. 5) and the structure of 3rd Embodiment (FIG. 6). The components of the first to fourth embodiments can be freely combined. For example, the rounded rear end 23 of the additional structure 20 in the second embodiment is added to the configuration of the other embodiments. May be.

11 Stern 15 Bottom plate 20 Additional structure

Claims

An offshore floating structure having a buttocks flow type stern, comprising an additional structure provided on an outer wall surface of the bottom plate of the stern, the additional structure extending in a ship length direction, the width of the additional structure being a front end An offshore floating structure characterized by being 50% or more of the ship width and becoming narrower toward the rear.
The offshore floating structure according to claim 1, wherein the length of the additional structure in the ship length direction is 70% to 190% of the ship width.
The offshore floating structure according to claim 1 or 2, wherein an outer surface of the additional structure forms a triangular prism surface having an axis extending in a vertical direction.
The offshore floating structure according to any one of claims 1 to 3, wherein a width of a front end of the additional structure is the same as a ship width.
The offshore floating structure according to any one of claims 1 to 4, wherein a corner portion at a lower end of the additional structure is formed in a round shape over the entire length of the additional structure.