Ships

Abstract

To provide a ship capable of reducing the dead space between a tank cover and a cargo tank.SOLUTION: A ship comprises a hull, tanks mounted in the hull, a plate-like tank cover to cover the tank, and a first reinforcement member provided on the outer face of the tank cover and extending to the ship width direction to pass above the tank cover.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to marine vessels. [Background technology]

[0002] Ships that transport liquefied gases such as liquefied carbon dioxide and LNG (Liquefied Natural Gas) are equipped with cargo tanks that store the liquefied gas. Patent Document 1 discloses the configuration of a ship that includes a cargo tank whose upper portion protrudes from the upper deck of the ship's hull and a tank cover that covers the upper portion of the cargo tank. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-14438 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the gross tonnage of a ship, which affects the equipment it is equipped with and port entry fees, is calculated according to the volume of the ship's internal space. In the case of a ship equipped with a tank cover as described in Patent Document 1, the volume of the ship's internal space includes the volume inside the tank cover as well as the volume inside the hull. Therefore, in order to enlarge the cargo tank without increasing the gross tonnage, it is desirable to reduce the gap between the tank cover and the cargo tank as much as possible. However, there is dead space between the tank cover and the cargo tank, and it is difficult to further reduce this dead space.

[0005] The present disclosure has been made to solve the above-mentioned problem, and has an object to provide a ship that is capable of reducing the dead space between a tank cover and a cargo tank. [Means for solving the problem]

[0006] In order to solve the above problems, a vessel according to the present disclosure includes a hull, a tank, a tank cover, a first reinforcing member, and A second reinforcing member; The tank is provided in the hull. It is cylindrical and extends from bow to stern. The tank cover covers the tank and is plate-shaped. The first reinforcing member is provided on an outer surface of the tank cover. The first reinforcing member extends in the width direction of the hull so as to pass above the tank cover. The second reinforcing member is provided on an outer surface of the tank cover and extends in a bow-stern direction of the hull. The tank cover has a polygonal arch shape in a cross section perpendicular to the central axis of the tank, the tank cover having a plurality of straight line portions extending in a tangential direction of the tank and a plurality of corner portions connecting the straight line portions and formed at intervals in a circumferential direction centered on the central axis, both ends of the first reinforcing member are connected to an upper deck of the hull, the first reinforcing members are arranged at intervals in the bow-stern direction, and the second reinforcing members are provided on the outer surface of the straight line portions and arranged at intervals in the width direction of the ship, connecting adjacent first reinforcing members in the bow-stern direction. Effect of the Invention

[0007] According to the present disclosure, the dead space between the tank cover and the cargo tank can be reduced. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a side view showing an overall configuration of a marine vessel according to an embodiment of the present disclosure. [Diagram 2] FIG. 1 is a plan view showing an overall configuration of a marine vessel according to an embodiment of the present disclosure. [Diagram 3] 1 is a half cross-sectional view of a cargo tank and a tank cover provided in a marine vessel according to an embodiment of the present disclosure, viewed from the bow-stern direction. FIG. [Figure 4] FIG. 2 is a side view showing a cargo tank, a tank cover, and a reinforcing member provided in the marine vessel according to the embodiment of the present disclosure. [Diagram 5] FIG. 2 is a plan view showing a cargo tank, a tank cover, and a reinforcing member provided in a marine vessel according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a vessel according to an embodiment of the present disclosure will be described with reference to FIGS. 1 to 5. FIG. (Vessel configuration) 1 to 3, the ship 1 exemplified in this embodiment is a liquefied gas carrier that transports liquefied carbon dioxide. The object to be transported by the ship 1 is not limited to liquefied carbon dioxide, and may be other liquefied gases such as LNG (Liquefied Natural Gas) and LPG (Liquefied Petroleum Gas). The ship 1 at least includes a hull 2, a tank 10, a tank cover 20, and a reinforcing member 30.

[0010] (Hull configuration) The hull 2 ​​has a pair of side walls 3A, 3B, a bottom plate 4 (see FIG. 1), and an upper deck 5 that form its outer hull. The side walls 3A, 3B have a pair of side wall shells that form the port and starboard sides, respectively. The bottom plate 4 has a bottom shell plate that connects the side walls 3A, 3B. The pair of side walls 3A, 3B and the bottom plate 4 give the outer hull 2 ​​a U-shape in a cross section perpendicular to the bow-stern direction FA. The upper deck 5 illustrated in this embodiment is a full-length deck that is exposed to the outside. A superstructure 7 having accommodation areas is formed on the upper deck 5 of the hull 2.

[0011] A cargo carrying section 8 (in other words, a cargo hold) is formed inside the hull 2, closer to the bow 2a than the superstructure 7. The cargo carrying section 8 is recessed toward the bottom 4 of the ship below in the vertical direction Dv with respect to the upper deck 5, and has an opening that opens upward.

[0012] (Tank configuration) Tanks 10 are arranged in the cargo carrying section 8. In this embodiment, the hull 2 ​​is shown to have multiple (e.g., two) tanks 10 arranged at intervals in the bow-stern direction FA. The number of tanks 10 arranged in the cargo carrying section 8 of the hull 2 ​​and the layout of the tanks 10 can be changed as appropriate.

[0013] Fig. 4 is a side view showing a cargo tank, a tank cover, and a reinforcing member provided in the marine vessel according to the embodiment of the present disclosure, and Fig. 5 is a plan view showing a cargo tank, a tank cover, and a reinforcing member provided in the marine vessel according to the embodiment of the present disclosure. As shown in FIG. 4 and FIG. 5, the tank 10 has a cylindrical shape extending in the bow-stern direction FA. The tank 10 can store liquefied carbon dioxide therein. The tank 10 includes a tubular portion 12 and a head plate portion 13. The tubular portion 12 extends in the bow-stern direction FA as the longitudinal direction Dx. In this embodiment, the tubular portion 12 has a cylindrical shape with a circular cross section perpendicular to the longitudinal direction Dx. The head plate portions 13 are formed on both sides of the tubular portion 12 in the longitudinal direction Dx. Each head plate portion 13 has a hemispherical shape that is convex toward the outside in the longitudinal direction Dx, and closes both sides of the tubular portion 12 in the longitudinal direction Dx. Note that, although the tank 10 has been described as being cylindrical, the tank 10 is not limited to being cylindrical. For example, the tank 10 may be spherical, rectangular, or the like.

[0014] As shown in Figures 3 and 4, an upper portion 10a of the tank 10 in the vertical direction Dv protrudes above the upper deck 5 of the hull 2. As shown in Figure 3, the upper portion 10a of the tank 10 protruding above the upper deck 5 forms an arc shape extending in the circumferential direction Dc of the tank 10 centered on the tank central axis C in a cross-sectional view perpendicular to the tank central axis C extending in the bow-stern direction FA.

[0015] The tank cover 20 has a plate shape. The tank cover 20 of this embodiment is formed of a material such as metal. The tank cover 20 is disposed on the upper deck 5 and covers the tank 10 from above in the vertical direction Dv. The ship 1 of this embodiment includes a plurality of tank covers 20 that respectively cover the plurality of tanks 10.

[0016] The tank cover 20 is disposed on the outer side Dro of the tank 10 in the radial direction Dr centered on the tank central axis C at a distance. In other words, the inner surface 20g of the tank cover 20 facing the tank 10 is disposed on the outer surface of the upper part 10a of the tank 10 at a distance in the radial direction Dr. In other words, the tank cover 20 rises upward from the periphery of the opening of the cargo loading section 8, and closes the opening of the cargo loading section 8 from above while covering the upper part 10a of the tank 10. The tank cover 20 extends in the circumferential direction Dc centered on the tank central axis C so as to follow the upper part 10a of the tank 10. The tank cover 20 illustrated in this embodiment is formed in a polygonal arch shape having a plurality of straight line parts extending in the tangential direction of the tank 10 and a plurality of corner parts 20c formed at intervals in the circumferential direction Dc connecting these straight line parts in a cross section perpendicular to the tank central axis C shown in FIG. 3.

[0017] In this embodiment, the tank cover ends 20a of the tank cover 20 located on both sides in the circumferential direction Dc centered on the tank central axis C are joined to the upper deck 5 by welding or the like. In this embodiment, the upper deck 5 arranged around the tank 10 has a protruding portion 53 protruding toward the inside of the cargo carrying section 8, in other words, toward the tank 10 side in the ship's width direction Dw and the bow-stern direction FA. The protruding portion 53 supports the tank cover ends 20a from below. The tank 10 of this embodiment has an oval shape with a constant dimension in the ship's width direction Dw of the cylindrical portion 12 when viewed from above. In this embodiment, the dimension in the ship's width direction Dw of the portion of the tank cover 20 covering the cylindrical portion 12 is constant, and the dimension in the ship's width direction Dw of the portion of the tank cover 20 covering the end plate portion 13 of the tank cover 20 decreases toward the bow 2a side and the stern 2b side, respectively.

[0018] The reinforcing member 30 is a member that reinforces the plate-shaped tank cover 20. The reinforcing member 30 is provided along the tank cover 20. In this embodiment, the reinforcing member 30 includes a first reinforcing member 31 and a second reinforcing member 32.

[0019] The first reinforcing members 31 extend in the circumferential direction Dc centered on the tank central axis C, and are arranged at intervals in the bow-stern direction FA. The first reinforcing members 31 are arranged on the outer side Dro in the radial direction Dr with respect to the tank cover 20. More specifically, the first reinforcing members 31 are provided along the outer surface 20f of the tank cover 20. The first reinforcing members 31 of this embodiment are continuously formed so as to pass from one side in the ship width direction Dw to the upper side of the tank cover 20 and reach the other side in the ship width direction Dw. Here, the outer surface 20f of the tank cover 20 is the surface of the tank cover 20 facing outward, opposite to the inner surface 20g facing the tank 10 side described above. The first reinforcing members 31 are formed so as to protrude outward in the radial direction Dr from the outer surface 20f of the tank cover 20.

[0020] As shown in FIG. 5, the first reinforcing members 31 each extend in the ship width direction Dw when viewed from above. The first reinforcing members 31 illustrated in this embodiment are arranged parallel to each other when viewed from above. The first reinforcing members 31 are formed in a polygonal arch shape in a cross section perpendicular to the tank central axis C, similar to the tank cover 20. The first reinforcing members 31 can be formed, for example, from a steel frame material having an H-shaped or I-shaped cross section, a steel pipe material having a rectangular cross section, or the like. The first reinforcing members 31 in this embodiment are joined to the outer surface 20f of the tank cover 20 by, for example, welding, bolt fastening, or the like. The first reinforcing members 31 illustrated in this embodiment are provided in the tank cover 20 at a position outside the cylindrical portion 12 of the tank 10 in the radial direction Dr. The first reinforcing members 31 may be provided not only in the cylindrical portion 12 of the tank 10 but also in a position outside the end plate portion 13 in the radial direction Dr. In this embodiment, the case where the multiple first reinforcing members 31 are arranged at equal intervals in the bow-stern direction FA is illustrated, but the intervals are not limited to being equal.

[0021] The reinforcing member ends 31a of the first reinforcing member 31 located on both sides in the circumferential direction Dc are each joined to the upper deck 5 by welding, bolting, etc. The reinforcing member ends 31a of the first reinforcing member 31 are each supported from below by the above-mentioned overhanging portions 53.

[0022] The second reinforcing member 32 extends in the bow-stern direction FA. In other words, the second reinforcing member 32 extends in the direction of the tank central axis C when viewed from above. The second reinforcing members 32 are arranged at intervals in the circumferential direction Dc. The second reinforcing members 32 are arranged outside the tank cover 20 in the radial direction Dr. More specifically, the second reinforcing member 32 is provided along the outer surface 20f of the tank cover 20. The second reinforcing member 32 of this embodiment is continuously formed so as to pass above the tank cover 20 from the bow 2a side in the bow-stern direction FA to the stern 2b side in the bow-stern direction FA. The second reinforcing member 32 is formed to protrude outward in the radial direction Dr from the outer surface 20f of the tank cover 20, similar to the first reinforcing member 31. In other words, the reinforcing members 30 of this embodiment (the first reinforcing member 31 and the second reinforcing member 32) do not protrude from the inner surface 20g of the tank cover 20 toward the tank 10 side.

[0023] The second reinforcing members 32 are arranged at intervals in the ship width direction Dw when viewed from above. In other words, the second reinforcing members 32 are arranged at intervals in the circumferential direction Dc centered on the tank central axis C. The second reinforcing members 32 can be formed, for example, from steel frame material with an H-shaped or I-shaped cross section, steel pipe material with a rectangular cross section, angle material with an L-shaped cross section, or the like. The second reinforcing members 32 in this embodiment are joined to the outer surface 20f of the tank cover 20 by, for example, welding, bolting, or the like.

[0024] 4 and 5, the second reinforcing member 32 is formed so as to connect the first reinforcing members 31 adjacent to each other in the fore-aft direction FA. As a result, the multiple first reinforcing members 31 and the multiple second reinforcing members 32 are arranged in a lattice pattern when viewed from above. The multiple second reinforcing members 32 illustrated in this embodiment extend parallel to each other along the tank central axis C between the first reinforcing member 31 located furthest to the bow in the fore-aft direction FA and the first reinforcing member 31 located furthest to the stern when viewed from above.

[0025] (Action and effect) The ship 1 of the above embodiment is provided with a first reinforcing member 31 extending in the ship width direction Dw. This reinforces the tank cover 20. Therefore, the tank cover 20 itself can be made thinner than when the first reinforcing member 31 is not provided. Furthermore, since the first reinforcing member 31 is provided on the outer surface 20f of the tank cover 20, there is no need to secure a space between the tank cover 20 and the tank 10 to place the first reinforcing member 31. Therefore, the gap between the tank cover 20 and the tank 10 can be reduced by shortening the interval between the inner surface 20g of the tank cover 20 and the outer surface of the tank 10, so that the dead space between the tank cover 20 and the tank 10 can be reduced. As a result, the volume of the internal space of the ship 1 is reduced, and it is possible to reduce the total tonnage that affects the installed equipment and port entry fees. Furthermore, by providing the first reinforcing member 31 only on the outer surface 20f side of the tank cover 20, there is no need to consider interference with the tank 10 when increasing the cross section of the first reinforcing member 31 to improve strength, and the degree of design freedom is increased.

[0026] In the above embodiment, the reinforcing member ends 31a on both sides of the first reinforcing member 31 are connected to the upper deck 5 of the hull 2. This allows the first reinforcing member 31 to be firmly fixed to the hull 2, thereby enhancing the reinforcing effect of the first reinforcing member 31 on the tank cover 20.

[0027] Furthermore, the ship 1 of the above embodiment includes, in addition to the first reinforcing member 31, a second reinforcing member 32 extending in the bow-stern direction FA. Therefore, the tank cover 20 can be reinforced more firmly. And, like the first reinforcing member 31, the second reinforcing member 32 is also provided only on the outer surface 20f side of the tank cover 20, so that the gap between the tank cover 20 and the tank 10 can be reduced, and the dead space between the tank cover and the cargo tank can be reduced. Also, by providing the second reinforcing member 32, it can be used as a scaffold when performing maintenance or inspection work on the tank cover 20. Therefore, there is no need to set up a separate scaffold when performing maintenance or inspection work, and the burden on the worker can be reduced.

[0028] Moreover, the second reinforcing member 32 in the above embodiment connects the first reinforcing members 31 adjacent to each other in the bow-stern direction FA. Therefore, the tank cover 20 can be reinforced more effectively by the first reinforcing member 31 and the second reinforcing member 32 extending in different directions.

[0029] Furthermore, in the above embodiment, a plurality of second reinforcing members 32 are disposed at intervals in the ship width direction Dw. Therefore, when viewed from above, the plurality of first reinforcing members 31 and the plurality of second reinforcing members 32 are arranged in a lattice pattern, which makes it possible to reinforce the tank cover 20 even more effectively.

[0030] (Other embodiments) Although the embodiments of the present disclosure have been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like that do not depart from the gist of the present disclosure are also included.

[0031] In the above embodiment, the case where both the first reinforcing member 31 and the second reinforcing member 32 are provided has been described. However, the present invention is not limited to the case where both the first reinforcing member 31 and the second reinforcing member 32 are provided. For example, only one of the first reinforcing member 31 and the second reinforcing member 32 may be provided as necessary. Also, in the above embodiment, the case where a plurality of second reinforcing members 32 are provided at intervals in the ship width direction Dw has been described, but only one second reinforcing member 32 may be provided.

[0032] Furthermore, in the above embodiment, the first reinforcing member 31 is formed in a straight line extending in the ship's width direction Dw when viewed from above, but the shape of the first reinforcing member 31 is not limited to a straight line extending in the ship's width direction Dw when viewed from above. The shape of the first reinforcing member 31 may be, for example, a curved line extending in the ship's width direction Dw when viewed from above, a combination of a straight line and a curved line, a zigzag shape, etc.

[0033] Also, in the above embodiment, a case has been described in which the reinforcing member end 31a of the first reinforcing member 31 is connected to the upper deck 5 of the hull 2. However, the reinforcing member end 31a of the first reinforcing member 31 may be connected to the upper deck 5 as necessary, and for example, among the multiple reinforcing member end portions 31a, some or all of the reinforcing member end portions 31a may not be connected to the upper deck 5.

[0034] In the above embodiment, the first reinforcing member 31 extends continuously from one side to the other side in the ship width direction Dw. However, the first reinforcing member 31 may extend intermittently from one side to the other side in the ship width direction Dw. Similarly, the second reinforcing member 32 extends continuously from the bow 2a side to the stern 2b side in the fore-aft direction FA, but may extend intermittently from the bow 2a side to the stern 2b side in the fore-aft direction FA. In addition, the first reinforcing member 31 and the second reinforcing member 32 are connected to each other, but the first reinforcing member 31 and the second reinforcing member 32 may not be connected to each other.

[0035] Furthermore, in the above embodiment, some of the multiple first reinforcing members 31 and the multiple second reinforcing members 32 may be provided on the inner surface 20g of the tank cover 20. In that case, the first reinforcing members 31 and the second reinforcing members 32 provided on the inner surface 20g of the tank cover 20 are preferably disposed at positions that avoid interference with the tank 10. For example, the second reinforcing members 32 may be provided on the inner surface 20g at the corner portions 20c of the tank cover 20.

[0036] Furthermore, in the above embodiment, the gap between the tank 10 and the tank cover 20 is an empty space, but for example, a heat insulating material that insulates the tank 10 from heat may be disposed therein.

[0037] <Additional Notes> The ship 1 described in the embodiment can be understood, for example, as follows.

[0038] (1) A ship 1 in a first embodiment comprises a hull 2, a tank 10 provided in the hull 2, a plate-shaped tank cover 20 covering the tank 10, and a first reinforcing member 31 provided on an outer surface 20f of the tank cover 20 and extending in the ship width direction Dw of the hull 2 ​​so as to pass above the tank cover 20.

[0039] The ship 1 is provided with a first reinforcing member 31 extending in the ship width direction Dw. This reinforces the tank cover 20. Therefore, the tank cover 20 itself can be made thinner than when the first reinforcing member 31 is not provided. Since the first reinforcing member 31 is provided on the outer surface 20f of the tank cover 20, it is not necessary to secure a space between the tank cover 20 and the tank 10 to place the first reinforcing member 31. Therefore, the gap between the tank cover 20 and the tank 10 can be reduced, and the dead space between the tank cover and the cargo tank can be reduced. As a result, the volume of the internal space of the ship 1 is reduced, and it is possible to reduce the total tonnage, which affects the equipment to be installed and the port entry fee.

[0040] (2) The ship 1 according to a second aspect is the ship 1 of (1), in which both ends of the first reinforcing member 31 are connected to the upper deck 5 of the hull 2.

[0041] This allows the first reinforcing member 31 to be firmly fixed to the hull 2, thereby enhancing the reinforcing effect of the first reinforcing member 31 on the tank cover 20.

[0042] (3) The ship 1 according to a third aspect is the ship 1 of (1) or (2), further comprising a second reinforcing member 32 provided on the outer surface 20f of the tank cover 20 and extending in the bow-stern direction FA of the hull 2.

[0043] As a result, the tank cover 20 can be more strongly reinforced by the second reinforcing member 32 extending in the bow-stern direction FA than when only the first reinforcing member 31 is provided.

[0044] (4) The ship 1 according to a fourth aspect is the ship 1 of (3), in which the second reinforcing member 32 is provided on an outer surface 20 f of the tank cover 20.

[0045] This makes it possible to reduce the gap between the tank cover 20 and the tank 10, thereby reducing the dead space between the tank cover 20 and the tank 10. In addition, the second reinforcing member 32 can be used as a foothold during maintenance and inspection work.

[0046] (5) The ship 1 in the fifth aspect is the ship 1 of (3), wherein the first reinforcing members 31 are arranged at intervals in the bow-stern direction FA, and the second reinforcing members 32 connect adjacent first reinforcing members 31 in the bow-stern direction FA.

[0047] As a result, since a plurality of first reinforcing members 31 and second reinforcing members 32 are assembled, the tank cover 20 can be reinforced even more effectively.

[0048] (6) The ship 1 according to a sixth aspect is any one of the ships 1 according to (3) to (5), in which the second reinforcing members 32 are arranged at intervals in the ship's width direction Dw.

[0049] As a result, the multiple first reinforcing members 31 and the multiple second reinforcing members 32 are arranged in a lattice pattern when viewed from above, so that the tank cover 20 can be reinforced even more effectively. [Explanation of symbols]

[0050] 1...ship 2...hull 2a...bow 2b...stern 3A, 3B...shipside 4...bottom 5...upper deck 7...superstructure 8...cargo space 10...tank 10a...upper part 12...cylindrical part 13...head plate part 20...tank cover 20a...tank cover end 20c...corner 20f...outer surface 20g...inner surface 30...reinforcing member 31...first reinforcing member 31a...reinforcing member end 32...second reinforcing member 53...projection C...tank central axis Dc...circumferential direction Dr...radial direction Dro...outer side Dv...vertical direction Dw...ship width direction Dx...longitudinal direction FA...fore-aft direction

Claims

[Claim 1] The hull and A cylindrical tank provided in the hull and extending in a bow-stern direction; A plate-shaped tank cover that covers the tank; A first reinforcing member provided on an outer surface of the tank cover and extending in a ship width direction of the hull so as to pass above the tank cover; A second reinforcing member provided on an outer surface of the tank cover and extending in a bow-stern direction of the hull; Equipped with the tank cover has a polygonal arch shape in a cross section perpendicular to the central axis of the tank, the tank cover having a plurality of straight line portions extending in a tangential direction of the tank and a plurality of corner portions connecting the straight line portions and formed at intervals in a circumferential direction around the central axis, Both ends of the first reinforcing member are connected to the upper deck of the hull, The first reinforcing member is disposed in a plurality of positions spaced apart in the bow-stern direction, The second reinforcing members are provided on an outer surface of the straight portion, are arranged at intervals in the ship width direction, and connect adjacent first reinforcing members in the bow-stern direction.

Images