JP4401346B2 - Double hull structure in ship engine room - Google Patents

Description

  The present invention prevents a large amount of seawater from being flooded into a ship engine room due to a ship accident such as a collision, and also prevents marine pollution due to leakage of fuel oil from a fuel tank (FOT) provided in the ship engine room. Concerning structure.

In recent years, fuel oil spill accidents due to ship collision accidents tend to increase against the background of increasing ship volume. In particular, as ships grow in size, fuel oil will be loaded in the thousands of tons, not only leakage of cargo oil loaded in large quantities, but also marine pollution caused by fuel oil spills and engine room safety. Has come to be considered.
However, the ship side skin of the ship engine room has a single-plate structure and can withstand the water pressure of the open ocean. Cracks or breakage, seawater invades into the large-capacity marine engine room, sinks, and cracks in the fuel oil tank wall installed in contact with the ship's outer skin If the oil tank is damaged, the fuel oil may directly flow out to the sea, which may cause sea pollution.

  By the way, the technique of making a ship ship bottom into a double hull structure is proposed conventionally, for example, there exists a technique disclosed by Unexamined-Japanese-Patent No. 5-305895 as a typical thing. This technology is related to a double hull tanker (double hull tanker) that has a double hull side and bottom, and is intended to ensure restoration performance when the hull is damaged. In order to achieve this, the left ballast tank and the right ballast tank, which are continuously formed from the side ballast tank portion along the left and right ship side skin plates to the bottom ballast tank portion along the ship bottom skin plate, are mutually connected to the bottom ballast tank. In order to make the inside of both ballast tanks communicate with each other when the ship side skin or the ship bottom skin is damaged in one of the left ballast tank and the right ballast tank. , Equipped with a rupture disk that breaks and opens at a load pressure higher than a predetermined value due to ingress water on the centerline girder One in which the.

Conventional general cargo ships including this type of tanker often have a ship engine room at the rear of the ship because of the demand for securing the maximum cargo space.
Taking a conventional general cargo ship as an example, an outline of the arrangement of the engine room will be described with reference to the drawings.
FIG. 3 is a stern side longitudinal sectional view of a conventional general cargo ship, with the right side being the bow (not shown) and the left side being the stern. FIG. 4 is a port side perspective view of a ship engine room portion of a conventional general cargo ship.

  In FIG. 3, the ship engine room 110 is provided in the rear part of the cargo ship 100. Then, the ship engine room 110 stands up perpendicular to the traveling direction of the cargo ship 100 with the first deck 121 directly above the bottom shell plate 102 as the floor and the fifth deck 125, which is the dry deck, as the ceiling. The engine room front wall 126 on the bow side and the engine room rear wall 128 on the stern side, the port side outer plate 104 and the starboard side outer plate (not shown) are enclosed.

As shown in FIG. 3, a second deck 122, a third deck 123, and a fourth deck 124 are disposed between the tank top (hereinafter referred to as “first deck”) 121 and the fifth deck 125. The main engine 112 is installed on the first deck 121, and in the installed part of the main engine 112, there is a so-called atrium space where the second deck 122, the third deck 123, and the fourth deck 124 are not present. And, for example, other devices are arranged on each deck in the ship engine room 110 such that the generator 114 is installed on the third deck 123.
The fuel tank 116 is formed of steel plates on the port side outer plate 104, the fifth deck 125, the engine room front wall 126, and the other three surfaces, that is, the fuel tank inner wall 132, the fuel tank rear wall 130, and the bottom surface. The fuel is stored. Therefore, as shown in FIG. 4, the conventional ship engine room 110 has a double bottom only at the bottom, and the port side outer plate 104 and starboard side outer plate (not shown) on the ship side have a single plate structure. ing. Although the ship side has a single plate structure, a girder, a rib, and the like are provided, and the structure that can sufficiently withstand the water pressure in the open ocean has been described above.
JP-A-5-305895

The so-called double hull structure disclosed in JP-A-5-305895 is intended to prevent the leakage of cargo from the cargo tank when the hull is damaged. The invention relates to the ballast tank portion, and the ship engine room structure itself is not a double hull structure. This is because, on the one hand, it is necessary to maximize the cargo capacity of the ship, and on the other hand, due to the demand for improved propulsion performance, it is necessary to have a structure with the front and rear parts of the hull thinned. This was partly because the main engine 112 had to be installed in the tank top (“first deck”) 121 of the vehicle. Furthermore, in a ship that requires a high ship speed, the main engine 112 must be larger and have a structure with a thinner front and rear of the hull. It was unavoidable to install the engine room structure in a double hull structure because it had to be installed further forward of the deck 121. In addition, if the engine room has a double hull structure,
(1) Since the effective width of the floor of the ship engine room decreases, the cargo loading space 118 is compressed and the cargo loading amount decreases.
(2) The ship engine room has a demerit that the initial cost including the construction cost increases due to the double hull structure.
(3) Compared to the above-mentioned disadvantages, even if there is a leakage of fuel oil from the fuel tank in the ship engine room when the hull is damaged, the amount is small and there is a great risk that the damage will be serious. It is considered that there was no technical idea that the engine room had to have a double hull structure.

  Therefore, in consideration of the above disadvantages, the present invention seeks to provide a safe ship and a ship structure for the purpose of preventing marine pollution by reducing the probability of seawater flooding and oil spilling into the ship engine room. To do.

In order to achieve the above object, a double hull structure of a ship engine room according to claim 1 of the present application includes a front wall of the engine room on the bow side and a rear wall of the engine room on the stern side that are set up perpendicular to the traveling direction of the ship. In the engine room surrounded by the port side outer plate and the starboard side outer plate (hereinafter collectively referred to as the “board side outer plate”), the first deck, which is the floor, The second deck,..., The (n-1) th deck (hereinafter referred to as “each deck” when not specified) in order between the deck and the nth deck (n is a natural number of 3 or more). In addition, on the positions (L ₁ ), (L ₂ ),..., (L _n-1 ) respectively spaced apart from the heel-side outer plate, the port-side inner wall and starboard-side inner wall (hereinafter referred to as these) When called generically, it is called “the inner wall on the heel side”). Is set, stepwise by said respective deck and the ship's side inner wall in a cross-sectional view, or from said _{(L 1)} to _{(L 2),} to the _{(L 2) (L 3)} , ···, ( L _n-1 ) to (L _n ) ((L _n ) is a position (L _n ) at a predetermined distance from the heel-side outer plate of the n-th deck, which is the dry breech deck), in the cross-sectional view, The heel side inner wall is formed in substantially the same shape as the heel side outer plate, the stern side floor surface in the engine room is formed as a second deck, and the first deck and the second deck at the position of the engine room rear wall. ,..., The distances from the respective inner walls of the (n-1) th deck to the outer side plates are α ₁ , α ₂ ,..., Α _n−1 , at the position of the engine room front wall , respectively. From the first inner side wall of the first deck, the second deck, ..., the (n-1) th deck When the distances to the side outer plates are β ₁ , β ₂ ,..., Β _n-1 , the predetermined distances are α ₁ > α ₂ >...> Α _n-1 and β _1. > Β ₂ >...> Β _n−1 , and gradually narrows from the engine room front wall side to the engine room rear wall side.

  According to the first aspect of the present invention, the shore side inner wall is provided in a watertight manner at a predetermined distance from the shore side outer plate of the ship engine room, and on the shore side, from the shore side outer plate and the shore side inner wall. It has become a double wall. In addition, the floor of the ship engine room is a double floor made up of the ship's bottom skin and the first deck. In other words, the ship engine room is in a state of floating at a predetermined distance from the ship's skin. . Therefore, when the hull is damaged, not only can seawater be prevented from entering the ship engine room, but also the fuel oil tank that is an accessory of the ship engine room is installed in the ship engine room. The probability of oil spilling is very low.

  By making the ship engine room a double hull structure, the risk of sinking due to damage to the outer plate and the risk of oil contamination are greatly improved. In addition, since the ship engine room has a double hull structure, the heat insulation effect in the ship engine room is increased, so that the capacity of the fuel-related heater-related equipment in the winter season can be reduced and energy saving can be achieved.

  According to the invention of claim 2 of the present application, since the heel side inner wall has a stepped shape in a cross-sectional view, the heel side inner wall may be attached perpendicularly to each deck, so that machining is easy. In addition, the staircase improves the strength of the double hull (double wall) and makes it less likely to be affected by external forces in the engine compartment. Even if there is an accident, there is an effect that the engine room is less damaged. Furthermore, since the stairs side inner wall is formed with a stepped deck composed of a vertical surface and a horizontal surface, many accessory devices such as various pumps can be installed in an orderly manner, and effective use of the installation location can be achieved.

  According to the third aspect of the present invention, the heel side inner wall is substantially the same shape as the heel side outer plate at a predetermined distance from the heel side outer plate in a cross-sectional view, and the heel side inner wall is perpendicular to each deck. However, the working volume is somewhat difficult compared with the invention according to claim 3, but the effective volume in the ship engine room is widened.

  Further, according to the invention of claim 4 of the present application, the floor surface on the stern side of the ship engine room is the second deck. In this case, the second deck below the floor is a propeller shaft space for connecting the main engine and the propeller, and since it also serves as a cover for the propeller shaft, it is safe and the second deck is the floor. Necessary accessory equipment can be placed on the engine room.

  Moreover, according to the invention which concerns on Claim 5 of this application, it is narrowing gradually from the engine room front wall side to the engine room rear wall side. The larger this distance, the higher the safety of the inner side wall when the outer side plate is damaged, but at the same time the effective floor width of the ship engine room is reduced, which leads directly to a decrease in the cargo load. A large separation distance is required. However, the well-balanced separation distance is determined by the width of the ship and the size of the main engine, and cannot be generalized and is determined individually and specifically. As the ship goes to the stern, the width of the ship decreases, so even if the predetermined distance between the dredging outer plate and the dredging inner wall is gradually narrowed from the engine room front wall side to the engine room rear wall side, safety is improved. There is no impact.

  Hereinafter, Example 1 and Example 2 according to the best mode for carrying out the present invention will be described with reference to FIGS. 1, 2, and 3. FIG. 1 is a port side perspective view of the double hull structure of the marine engine room according to the first embodiment, and FIG. 2 is a port side perspective view of the double hull structure of the marine engine room according to the second embodiment. FIG. 3 is a stern-side longitudinal sectional view of a conventional cargo ship, but can be used as a stern-side longitudinal sectional view of a cargo ship according to Example 1 and Example 2, and will be described with reference to the figure.

  1 to 3, reference numeral 1 is a double hull structure of a marine engine room according to the first embodiment, reference numeral 2 is a double hull structure of a marine engine room according to the second embodiment, reference numeral 11 is a first inner side wall, and reference numeral 12 is a first hull structure. 2 is a third side wall, reference numeral 14 is a fourth side wall, reference number 20 is a side wall according to Example 2, reference number 31 is a stern side inner wall, reference number 100 is a cargo ship, reference number 102 is Ship bottom skin, 104 is a port side shell, 110 is a ship engine room, 112 is a main engine, 116 is a fuel tank, 121 is a first deck, 122 is a second deck, 123 is a third Reference numeral 124 denotes a fourth deck, reference numeral 125 denotes a fifth deck, reference numeral 126 denotes a front wall of the engine room, reference numeral 128 denotes a rear wall of the engine room, reference numeral 130 denotes a rear wall of the fuel tank, and reference numeral 132 denotes an inner wall of the fuel tank. In addition, the same code | symbol is attached | subjected about the same element in a conventional cargo ship.

  First, the configuration and operation of the double hull structure of the ship engine room according to the first embodiment will be described. The ship engine room 110 is surrounded by an engine room front wall 126, an engine room rear wall 128, a port side outer plate 104, and a starboard side outer plate (not shown), as in the conventional cargo ship 100. However, the double hull structure 1 of the ship engine room is mainly composed of a shore-side inner wall erected on the ship inner side of the ship bottom outer plate 102. The heel side inner walls are the first heel side inner wall 11, the second heel side inner wall 12, the third heel side inner wall 13 and the fourth heel side inner wall 14 which are vertical members, and the side edges of the second deck 122 which is a horizontal member. And the side end of the third deck 123 and the side end of the fourth deck 124, and the cross section is stepped.

That is, the engine room rear wall 128 and a position separated by a predetermined distance (β ₁ ) at the position of the engine room front wall 126 from the port side outer plate 104 of the first deck 121 that is the floor surface of the ship engine room 110. The first heel-side inner wall 11 is erected in a vertical direction from a line (L ₁ ) connecting the positions separated by a predetermined distance (α ₁ : not shown) at about the position along the port-side outer plate 104. The upper end of the first heel side inner wall 11 abuts on the second deck 122. Further, a position separated by a predetermined distance (β ₂ ) at the position of the engine room front wall 126 and a position separated by a predetermined distance (α ₂ ) at the position of the engine room rear wall 128 are generally along the port side outer plate 104. The second heel side inner wall 12 is erected in the vertical direction from above the connected line (L ₂ ), and the upper end of the second heel side inner wall 12 abuts on the third deck 123. Similarly, the third heel side inner wall 13 is erected from above the line (L ₃ ), its upper end is in contact with the fourth deck 124, and the fourth heel side inner wall 14 is erected from above the line (L ₄ ) The upper end abuts on the fifth deck 125 to form a heel side inner wall having a stepped cross section. The starboard side wall is similarly formed with a stepped cross section on the starboard side.

The predetermined distances (α) and (β) have a relationship of α ₁ > α ₂ > α ₃ > α ₄ and β ₁ > β ₂ > β ₃ > β _4, respectively. This is because the heel side outer plate is inclined inward while curving outward from the upper part to the lower part, the corner formed by the first deck 121 and the first heel side inner wall 11,..., And the fourth deck 124. This is because the corners formed by the fourth heel side inner wall 14 each maintain an effective separation distance from the port side outer plate. Further, β ₁ > α ₁ ,..., Β ₄ > α ₄ .

The floor of the ship engine room 110 is the first deck 121 on the bow side, but is the second deck 122 on the stern side. A main engine 112 (see FIG. 3) is installed on the first deck 121 on the bow side, but a propeller shaft (see FIG. 3) that extends from the main engine 112 below the second deck 122 on the stern side. It is a shaft space. A stern side inner wall 31 is erected between the first deck 121 and the second deck 122 on the floor of the ship engine room 110.
As in the conventional cargo ship, a fuel tank 116 is formed in contact with the engine room front wall 126 in the ship engine room 110. That is, the fuel tank 116 has a side plate of the second deck 122, a side plate of the third deck 123, and a side plate of the fourth deck 124 that constitute the stepped inner wall as a bottom plate, and the fifth deck 125 as a cover plate. The first heel side inner wall 11, the second heel side inner wall 12, the third heel side inner wall 13 and the fourth heel side inner wall 14, which constitute the heel side inner wall, the engine room front wall 126, the fuel tank inner wall 132, the fuel Surrounded by four wall surfaces of the tank rear wall 130.

  With the above-described configuration of the double hull structure 1 for the ship engine room, the ship engine room 110 holds the effective distance from the staircase side inner wall that holds the effective distance from the port side outer plate 104 and the starboard side outer plate (not shown). And the floor of the marine engine room 110 is a double floor made up of the bottom shell plate 102 and the first deck 121 or the second deck 122, so to speak, The ship engine room 110 is in a state of floating while maintaining a predetermined distance from the outer plate of the ship 100. Therefore, when the hull skin is damaged, not only can seawater be prevented from entering the marine engine room, but also the fuel tank 116, which is an accessory of the marine engine room 110, is installed in the marine engine room. The probability that the fuel oil in the fuel tank 116 will flow out is extremely small. Furthermore, if air is sealed in the space between the shore side outer plate and the shore side inner wall, and the space between the ship bottom outer plate 102 and the ship engine room 110, the heat retention performance in the ship engine room 110 increases because the air has low thermal conductivity.

  Next, the configuration and operation of the double hull structure of the ship engine room according to the second embodiment will be described. Since the structural difference between the double hull structure 1 of the ship engine room and the double hull structure 2 of the ship engine room lies in the inner side wall, the different inner side wall will be mainly described.

The double hull structure 2 of the marine engine room is mainly composed of a shore-side inner wall 20 erected on the inner side of the ship bottom outer plate 102. The heel side inner wall 20 is located at a predetermined distance (β ₁ ) at the position of the engine room front wall 126 from the port side side outer plate 104 of the first deck 121 and a predetermined distance at the position of the engine room rear wall 128 ( α ₁ (not shown) is a line (L ₁ ) connecting the distant position substantially along the port side outer plate 104, at the position of the engine room front wall 126 from the port side outer plate 104 at the level position of the second deck 122. A line (L ₂ : in FIG. 2) connecting a position separated by a predetermined distance (β ₂ ) and a position separated by a predetermined distance (α ₂ ) at the position of the engine room rear wall 128 along the port side outer plate 104. ...,... At a predetermined distance (β ₅ ) at the position of the engine room front wall 126 from the port side outer plate 104 at the level position of the fifth deck 124 and at the position of the engine room rear wall 128. A predetermined distance (α ₅ ) away And a wall (L ₅ ) connecting the positions approximately along the port side outer plate 104, respectively, and each having a substantially linear shape with a cross section substantially identical to the cross section of the port side outer plate 104. ing. Similarly, on the starboard side, a heel side inner wall having a cross section substantially the same shape as the cross section of the starboard side outer plate (not shown) is formed.
Since the predetermined distances (α) and (β) and the floor surface of the ship engine room 110 have the same configuration as the double hull structure 1 of the ship engine room, the description thereof is omitted.

  Due to the configuration of the double hull structure 2 of the ship engine room, the ship engine room 110 maintains a predetermined distance from the outer plate of the ship 100 by the double wall and the double floor, similarly to the double hull structure 1 of the ship engine room. And it is in a floating state. Therefore, the operation of the double hull structure 2 in the marine engine room is the same as that of the double hull structure 1 in the marine engine room, but the double hull structure 2 in the marine engine room is more in the marine engine room 110 than the double hull structure 1 in the marine engine room. The effective volume of is large.

FIG. 1 is a port side perspective view of a double hull structure of a marine engine room according to a first embodiment. FIG. 2 is a port side perspective view of a double hull structure of a marine engine room according to a second embodiment. FIG. 3 is a vertical cross-sectional view of the stern side of a conventional cargo ship. FIG. 4 is a perspective view of the port side of a ship engine room portion of a conventional cargo ship.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Double hull structure of ship engine room which concerns on Example 1 2 Double hull structure of ship engine room which concerns on Example 2 11 1st ridge side inner wall (the ridge side inner wall which concerns on Example 1)
12 2nd heel side inner wall (the heel side inner wall concerning Example 1)
13 3rd heel side inner wall (the heel side inner wall concerning Example 1)
14 4th heel side inner wall (the heel side inner wall concerning Example 1)
20 Mineral side wall according to Example 2 100 Cargo ship 102 Ship bottom skin 104 Port side skin 110 Ship engine room 116 Fuel tank 121 First deck 122 Second deck 123 Third deck 124 Fourth deck 125 Fifth deck 126 Engine room Front wall 128 Rear wall of engine room

Claims (1)

The engine room front wall on the bow side and the stern side engine room rear wall that are set up perpendicular to the traveling direction of the ship, the port side outer plate and the starboard side outer plate. In the engine room formed by being surrounded by
The second deck,..., The (n-1) deck (hereinafter, these are specified) between the first deck that is the floor and the nth deck (n is a natural number greater than or equal to 3) not time as "the deck" in.), a position separated a predetermined distance each from the ship's side outer plate _{(L 1), (L 2} ), ···, the port side on _{(L n-1)} An inner wall and a starboard side inner wall (hereinafter, collectively referred to as a “board side inner wall”) are vertically and vertically watertight up to the respective decks immediately above, and in a cross-sectional view, the side wall and the decks Stepwise, or from (L ₁ ) to (L ₂ ), from (L ₂ ) to (L ₃ ), ..., (L _n-1 ) to (L _n ) ((L _n ) is , A cross-sectional view to a position (L _n ) that is a predetermined distance away from the heel side outer plate of the nth deck that is the dry front deck The heel side inner wall is formed in substantially the same shape as the heel side outer plate,
The floor on the stern side in the engine room is formed as a second deck,
The distances from the respective inner side walls of the first deck, the second deck,..., The (n-1) th deck to the outer side outer plate at the position of the rear wall of the engine room are respectively α ₁ , α ₂ ,. ..., Α _n-1 , the distance from each heel side inner wall of the first deck, second deck,..., (N−1) deck to the heel side outer plate at the position of the engine room front wall When β ₁ , β ₂ ,..., Β _n-1 are set, the predetermined distances are α ₁ > α ₂ >...> Α _n-1 and β ₁ > β ₂ >. A double hull structure for a ship engine room, which is> β _n-1 and gradually narrows from the engine room front wall side to the engine room rear wall side.

Images