JP2019014453A - Vessel-shaped structure - Google Patents

Abstract

To provide a vessel-shaped structure capable of downsizing a hull without reducing capacity of a cargo hold by being capable of narrowing width of a vertical passage zone immediately below a top deck in a double hull on shipboard from a strength side and recovering property side in damage.SOLUTION: Vertical passage zones are formed in a plurality of water tight zones by dividing a vertical passage zone in a hull front to back direction by water tight horizontal partition walls having manholes in a hull structure provided with a double hull structure on a shipboard side provided with the vertical passage zone immediately below a top deck of the double hull structure provided on a side of a cargo range.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a ship-shaped structure, and more specifically, a longitudinal passage section that is provided directly below the upper deck of the double hull structure on the ship side and on the side of the cargo hold and extends in the longitudinal direction of the hull. The present invention relates to a ship-shaped structure provided.

  In the case of ships, if the cargo loading capacity is the same, it is possible to enter many ports, and to reduce the initial cost of ship construction, in other words, from the viewpoint of port compatibility and initial cost. As long as the captain, the width, and the depth are small, a compact hull is desired. Of these main features such as master, width, and depth, the width of the ship is severely restricted by canal traffic and is an important point that should be considered especially when increasing the cargo volume. .

  Therefore, to reduce the width of the hull (hull width) and reduce the size of the hull, reduce the volume of the cargo hold, such as reducing the width of the cargo hold such as a liquefied gas tank, or change the shape of the cargo hold. It is necessary to devise. In addition, when the cargo volume is increased while maintaining the size of the hull, it is necessary to narrow the width of the portion different from the cargo hold by increasing the width of the cargo hold.

  On the other hand, in liquefied natural gas carriers (LNG ships), container ships, etc., the lower part of the upper deck and the upper part inside the double side wall (double hull) that constitutes the hull, Longitudinal passage sections called under deck passages that run vertically through the entire length are provided, and are often used as passages and piping installation places for crew members and the like.

  For example, the hull is composed of a double hull structure (double hull structure) with an inner shell and an outer shell, which is used by workers for maintenance and inspection inside the hull while ensuring the hull strength of the cargo handling compartment. As a passage, there is a ship in which a duct keel is disposed at the center of the bottom of the hull and an under deck passage is disposed on the upper surface of both sides of the hull (see, for example, Patent Document 1).

  In addition, under deck passages are provided along the length of the hull at the top of the double shell structure, and the partition in the width direction of the hull for partitioning into a plurality of tank chambers also has a double shell structure. A hull structure of a liquefied gas carrier ship in which an under deck passage is also provided on the upper part of the partition wall of the structure has also been proposed (see, for example, Patent Document 2).

  As shown in FIGS. 6 to 10, in the liquefied gas carrier ship 1X according to the prior art, the under deck passage 20X is a watertight transverse bulkhead in the longitudinal direction (X direction) of the hull due to the characteristic of the use as a passage for passage. Without dividing, it is formed by one section extending over the entire cargo area R1. Structurally, the under deck passage 20X is configured to be surrounded by a ship side outer plate 3, a longitudinal partition wall 11a, an upper deck 4, and a floor surface (horizontal girder) 24 along the hull longitudinal direction. These longitudinal structures are provided with longitudinal stiffeners 3b, 11b, 4b and 24b, respectively, and the hulls are supported to support these longitudinal stiffeners 3b, 11b, 4b and 24b. A vertical girder 21X in the plane of the cross section is arranged.

  The vertical girder 21 </ b> X is provided with an arch-shaped (U-shaped) opening 23 in contact with the floor surface 24 so as to pass through the carriage. In order to avoid interference between the opening 23 and the longitudinal stiffeners 3b, 11b, 4b, and 24b, the distance between the opening 23 and the longitudinal stiffeners 3b, 11b, 4b, and 24b needs to be a certain distance or more. Therefore, the passage width BXa of the under deck passage 20X needs to be at least 2 m. The passage width BXa of the under deck passage 20X is the width BXb of the double hull structure 30 constituted by the ship side skin 3 on which the under deck passage 20X is disposed and the inner longitudinal partition wall 11a. Therefore, the problem of securing the passage width BXa of all the under deck passages 20X along the entire cargo area R1 in the longitudinal direction of the hull hinders the hull from being made compact.

  On the other hand, the ship needs to have the restoration performance at the time of damage specified by the international regulations, and the hull shape needs to satisfy the regulation regarding the stability at the time of damage. When considering the stability at the time of damage, in the case of the under-deck passage that has been completely passed through as described above, a collision that damages some part of the cargo area occurs and the under-deck passage is submerged. All the buoyancy in this underdeck passage section will be lost.

  Usually, since the area occupied by the cargo area of a ship occupies a large area in the longitudinal direction of the hull, the buoyancy lost due to the inundation of the under deck passage section is also increased, and the stability at the time of damage is significantly deteriorated. On the other hand, the stability at the time of damage is greatly affected by the size of the ship. Therefore, when reducing the width of the ship, it is necessary to consider the improvement of stability in case of damage.

JP 2011-148358 A Japanese Patent Laid-Open No. 06-336187

  In connection with this, the present inventors obtained the following knowledge after consideration. In other words, the longitudinal passage section (under deck passage) is not a full passage section, and vertical girder plates that are watertight transverse bulkheads are arranged in the longitudinal direction of the hull to form a plurality of watertight sections. The vertical girder has no arched openings, manholes are arranged, and the vertical girder plates, including non-watertight, are arranged densely in the hull longitudinal direction, thereby reducing the size of the longitudinal stiffener extending in the hull longitudinal direction. can do. As a result, the width of the longitudinal passage section can be reduced. In addition, even if the longitudinal passage section is narrowed, the number of watertight sections is increased, so that the stability at the time of damage can be improved.

  As a result, the width of the longitudinal passage section and the size of the same size as the width of the longitudinal passage section are secured while ensuring the size of the manhole required for the inspection of the hull structure and fittings and the removal of the injured person. The width of the heavy hull can be narrowed to 1.0 m to 1.99 m. Accordingly, it is possible to reduce the size of the hull without reducing the capacity of the cargo hold such as the liquefied gas tank by the amount that the longitudinal passage section is narrowed. Alternatively, the cargo hold width can be increased without increasing the ship width.

  The present invention has been made in view of the above situation, and its purpose is to determine the width of the longitudinal passage section directly below the upper deck in the double hull on the ship side, in terms of strength and stability in the event of damage. It is an object of the present invention to provide a hull-shaped structure that can be narrowed from the surface and can be downsized without reducing the capacity of the cargo compartment.

  In order to achieve the above object, the hull structure of the present invention has a double hull structure on the ship side, and is provided directly below the upper deck of this double hull structure and on the side of the cargo area. The longitudinal passage section is divided in the longitudinal direction by a watertight transverse bulkhead having a manhole, and the longitudinal passage section is divided into a plurality of watertight sections. Is formed and configured.

  According to this configuration, the longitudinal passage section arranged just below the upper deck in the double hull structure on the ship side is divided by the watertight transverse bulkhead, and a part of the watertight transverse bulkhead in the longitudinal passage section is divided. The vertical girders included in the hull are arranged on the ship's outer shell, which forms a double hull structure on the ship's side, the longitudinal bulkhead, the upper deck, etc. The size of the longitudinal stiffener, which is the longitudinal structural member provided, can be reduced. Thereby, the width of the longitudinal passage section can be reduced while avoiding the interference between the longitudinal stiffener and the manhole. In addition, since the manhole is provided, it is possible to secure a passage necessary for the inspection of the hull structure and the fittings and for carrying out the injured person.

  In addition, the vertical girder plates in the longitudinal passage section are densely provided, so that not only can the width be reduced in terms of strength, but also the longitudinal passage section is formed by a plurality of watertight sections, so that the hull caused by a collision, etc. It is possible to improve the restoration performance against the lateral inclination of the hull at the time of damage. As a result, the reduction in stability due to the narrowing of the ship width can be compensated, and the width can be narrowed from the aspect of securing the stability at the time of damage.

  As a result, the width of the double hull structure determined in consideration of the width of the longitudinal passage section can be reduced, and the hull can be made without reducing the width of the cargo section carrying the liquefied gas and the container. It can be downsized.

  Further, in the above-mentioned ship-shaped structure, the number Np of the watertight compartments partitioning the longitudinal passage section in the longitudinal direction of the hull is equal to or more than the number Nc of the cargo sections in the cargo area, more preferably twice the number Nc. As described above, the watertight transverse bulkhead can be provided at a place where it is easy to provide the watertight transverse bulkhead, and the watertight transverse bulkhead considering the breakage length when the hull is damaged can be appropriately disposed.

  Further, in the above ship-shaped structure, when the minimum width of the longitudinal passage section is 1.0 m or more and 1.99 m or less, the conventional longitudinal passage section is narrower than 2.0 m or more. In addition, it is possible to obtain an optimum width that comprehensively considers the strength surface, traffic surface, restoration performance surface at the time of damage, and the like.

  Further, in the above ship-shaped structure, the cargo compartment is a cargo compartment provided with a liquefied gas tank for storing liquefied gas, and the watertight transverse bulkhead is provided on an extension of the transverse bulkhead between the cargo compartment and the cargo compartment. If it is, it will become easy to provide this watertight horizontal partition, and workability will improve.

  Further, in the above-mentioned ship-shaped structure, if the manhole is not provided on the upper deck of the longitudinal passage section in the center of the hull, it is possible to prevent the hull longitudinal strength from being lowered by providing the manhole, The set longitudinal strength of the hull can be maintained, and manholes can be prevented from becoming obstacles when passing through the upper deck.

  According to the hull form structure of the present invention, the longitudinal passage section directly below the upper deck in the double hull on the ship side is divided in the longitudinal direction of the hull to increase the number of watertight sections, thereby improving strength and damage. Since the width of the longitudinal passage section can be narrowed from the standpoint of maintaining stability at the time, the hull can be downsized without reducing the capacity of the cargo section.

It is a side view which shows typically the structure of the liquefied gas carrier ship of embodiment which concerns on this invention. It is a top view which shows typically the structure of the liquefied gas carrier ship of FIG. FIG. 3 is an enlarged plan view schematically showing three examples of configurations of longitudinal passage sections in the liquefied gas carrier ship of FIG. 1. It is a cross-sectional view which shows the AA cross section of FIG. 3 typically. It is a front view which shows typically the structure of the vertical passage division of FIG. It is a side view which shows typically the structure of the liquefied gas carrier ship in a prior art. It is a top view which shows typically the structure of the liquefied gas carrier ship of FIG. It is an enlarged plan view which shows typically the structure of the longitudinal passage division in the liquefied gas carrier ship of FIG. It is a cross-sectional view which shows the BB cross section of FIG. 8 typically. It is a front view which shows typically the structure of the vertical passage division of FIG.

  Hereinafter, a ship-shaped structure according to an embodiment of the present invention will be described with reference to the drawings. Here, as this ship-shaped structure, a liquefied gas carrier ship provided with a MOSS type spherical liquefied gas tank will be described as an example.

  However, the ship-shaped structure of the present invention is not limited to this liquefied gas carrier ship, but other liquefied gas carrier ships, ships equipped with a liquefied gas fuel tank, container ships, ships with a double ship side, liquefied gas fuel tanks The present invention can also be applied to a floating structure provided with a liquefied gas storage facility such as a floating structure having a liquefied gas storage facility. In the case of a ship, it normally sails, but in the case of a floating structure, it should sail by self-navigation only when going to the offshore installation location, or towed by a tugboat etc. to the offshore installation location. become.

  As shown in FIGS. 1 and 2, the boat-shaped structure according to the embodiment of the present invention is a liquefied gas carrier 1, and is formed around the hull by a ship bottom 2, a ship side outer plate 3 and an upper deck 4, A cargo area R1 in which cargo compartments 11 having liquefied gas tanks 10 are arranged, and an engine room 5 is provided at the rear of the cargo area R1, in other words, at the stern side of the hull, and a propeller shaft extending rearward from the engine room 5 is provided. A propeller 6 is disposed, and a rudder 7 is provided behind the propeller 6. A residential area 8 having a voyage bridge 8a is provided on the stern engine room 5, and a chimney 9 for releasing exhaust gas generated by the engine in the engine room 5 into the atmosphere. Is provided.

  The cargo area R1 is provided with a spherical liquefied gas tank 10 called a MOSS tank for storing liquefied gas. A part of the liquefied gas tank 10 protrudes above the upper deck 4 and is provided in a row (four in this case) in a line in the longitudinal direction of the hull.

  As shown in FIGS. 3 to 5, the liquefied gas carrier 1 has a double hull structure 30 on the ship side, directly below the upper deck 4 of the double hull structure 30, and cargo. A longitudinal passage section 20 is provided on the side of the section 11 and extends in the hull longitudinal direction (X direction). This longitudinal passage section 20 is divided in the longitudinal direction of the hull by a watertight transverse partition wall 21 having a manhole 22, and the longitudinal passage section 20 is formed by a plurality of watertight sections. That is, the vertical passage section 20 is not a full passage section, and the watertight horizontal partition wall 21 is arranged in the hull longitudinal direction to form a plurality of watertight sections. Examples of the arrangement of the watertight horizontal partition walls 21 are illustrated in FIGS. 3 (a), 3 (b), and 3 (c).

  And if this watertight horizontal partition 21 is provided on the extension of the horizontal partition between the cargo compartment 11 and the cargo compartment 11, it will become easy to provide this watertight horizontal partition, and workability will improve.

  Further, by arranging the vertical girder plates in the longitudinal passage section 20 with a narrow interval in the longitudinal direction of the hull, the size of the longitudinal stiffener that protrudes inside the longitudinal passage section 20 and extends in the longitudinal direction of the hull. Can be reduced. This longitudinal stiffener includes a longitudinal stiffener 4b on the lower side of the upper deck 4, a longitudinal stiffener 3b on the inner side of the ship side outer plate 3, and a longitudinal side on the side of the longitudinal bulkhead 11a of the cargo compartment 11. There are a stiffener 11b, a longitudinal stiffener 24b below the floor plate (horizontal girder) 24, and the like. Accordingly, in the watertight horizontal partition wall 21, a manhole 22 having a watertight structure with a waterproof door or a bolted lid 22 a as shown in FIG. 5 is arranged instead of the arch-shaped opening shown in FIG. 10. Thereby, since the number of watertight divisions increases, even if the width Ba of the longitudinal passage division 20 becomes narrow, the stability at the time of damage can be maintained.

  Accordingly, the width Ba of the longitudinal passage section 20 is ensured while ensuring the size of the manhole (for example, 600 mm × 600 m, 600 mm × 800 mm) necessary for the inspection of the hull structure and the fittings and the removal of the injured person. And the width Bb of the double hull structure 30 on the ship side having the same size as the width Ba can be reduced to 1.0 m to 1.99 m. Accordingly, it is possible to reduce the size of the hull without reducing the capacity of the cargo hold such as the liquefied gas tank 10 by the amount that the longitudinal passage section 20 is narrowed. Alternatively, the width of the cargo compartment 11 can be increased without increasing the ship width.

  Then, the number Np of watertight compartments that divide the longitudinal passage section 20 in the hull longitudinal direction is set to be equal to or greater than the number Nc of the cargo sections 11, more preferably twice the number Nc. As a result, the watertight horizontal partition wall 21 can be provided in a place where it can be easily provided, and the watertight horizontal partition wall 21 in consideration of the breakage length when the hull is damaged can be provided at an appropriate site.

  Further, the minimum width of the longitudinal passage section 20 (referred to as the smallest width among the sections of the plurality of watertight sections dividing the longitudinal passage section 20 in the longitudinal direction of the hull) is 1.0 m or more and 1 .99m or less. More preferably, it is 1.0 m or more and 1.6 m or less. Thereby, the width BXa of the under deck passage 20X of the prior art as shown in FIGS. 6 to 10 can be made narrower than 2.0 m. At the same time, it is possible to obtain an optimum width that comprehensively considers the strength surface, the traffic surface, and the restoration performance surface at the time of damage.

  Further, in the center of the hull, more specifically, if there is no manhole on the upper deck 4 of the longitudinal passage section 20 in the range of 30% of the length between the vertical lines from the midship in the front-rear direction, a manhole is provided. Therefore, the hull longitudinal strength can be prevented from being lowered, and the strictly set hull longitudinal strength can be maintained, and the manhole can be prevented from becoming an obstacle when passing through the upper deck 4.

  In addition, if the entire passage 17 different from the longitudinal passage section 20 is provided on the liquefied gas tank 10 and above the upper deck 4, this whole hole without opening the manhole 22 of the watertight transverse partition wall 21. The cargo area R1 can be moved in the front-rear direction of the hull using the passage 17.

  According to this configuration, the longitudinal passage section 20 disposed immediately below the upper deck 4 in the double hull structure 30 on the ship side is divided by the watertight transverse partition wall 21, and the watertight lateral in the longitudinal passage section 20 is separated. The vertical girder including the bulkhead 21 as a part thereof is arranged with a narrow interval in the longitudinal direction of the hull so that the ship-side outer plate 3 constituting the ship-side double hull structure 30 and the inner vertical plate thereof are arranged. The longitudinal stiffeners 3b, 11b, 4b, which are longitudinal structural members provided on the partition wall 11a, the upper deck 4 and the like, can be reduced in size. Thereby, the width Ba of the longitudinal passage section 20 can be narrowed while avoiding interference between the longitudinal stiffeners 3b, 11b and 4b and the manhole 22. In addition, since the manhole 22 is provided, the passage required for the inspection of the hull structure and the fittings and the removal of the injured person can be secured.

  Further, by providing the watertight transverse partition wall 21, not only can the width Ba be reduced in terms of strength, but also the longitudinal passage section 20 is formed by a plurality of watertight sections. The restoration performance with respect to the horizontal inclination can be improved. As a result, the reduction in stability due to the narrowing of the ship width can be compensated, and the width can be narrowed from the aspect of securing the stability at the time of damage.

  As a result, the width Bb of the double hull structure 30 determined in consideration of the width Ba of the longitudinal passage section 20 can be reduced, and the width of the cargo section 11 on which liquefied gas or a container is mounted is reduced. The hull can be downsized without any problems.

  Therefore, according to the natural gas carrier 1 of the above embodiment, the longitudinal passage section 20 directly below the upper deck 4 in the double hull structure 30 on the ship side is divided in the longitudinal direction of the hull so that the number of watertight sections By increasing the width, the width Ba of the longitudinal passage section 20 can be narrowed from the viewpoint of strength and maintenance of damage stability, so that the hull can be downsized without reducing the capacity of the liquefied gas tank 10. Become.

DESCRIPTION OF SYMBOLS 1, 1X Liquefied gas carrier 3 Ship side outer plate 3b Longitudinal stiffener 4 Upper deck 4b Longitudinal stiffener 10 Liquefied gas tank 11 Cargo compartment 11b Longitudinal stiffener 17 Whole passage 20 Longitudinal passage compartment 20X Under deck passage 21 Watertight transverse bulkhead 21X Vertical girder plate 22 Manhole 22a Bolt-tight lid 23 Arch-shaped opening 24 Bottom plate (horizontal girder)
24b Longitudinal stiffener 30 Double hull structure Ba, BXa Longitudinal passage section width Bb, BXb Double hull width R1 Cargo area

Claims (5)

A hull form structure having a double hull structure on the ship side, and a longitudinal passage section that is provided directly below the upper deck of this double hull structure and on the side of the cargo area and extending in the longitudinal direction of the hull In things,
A ship-shaped structure in which the longitudinal passage section is divided by a watertight transverse bulkhead having a manhole in the longitudinal direction of the hull, and the longitudinal passage section is formed by a plurality of watertight sections.   2. The ship-shaped structure according to claim 1, wherein the number Np of the watertight compartments partitioning the longitudinal passage section in the longitudinal direction of the hull is equal to or greater than the number Nc of cargo compartments in the cargo area.   The ship-shaped structure according to claim 1 or 2, wherein a minimum width of the longitudinal passage section is 1.0 m or more and 1.99 m or less.   The cargo section is a cargo section provided with a liquefied gas tank for storing liquefied gas, and the watertight transverse bulkhead is provided on an extension of the transverse bulkhead between the cargo section and the cargo section. The ship-shaped structure of any one of -3.   The ship-shaped structure according to any one of claims 1 to 4, wherein a manhole is not provided on the upper deck of the longitudinal passage section in the center of the hull.

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