JP2018030467A - Bulk carrier - Google Patents

Abstract

[PROBLEMS] To optimize the scale of a bulk carrier, improve the balance of load distribution between longitudinal strength members and lateral strength members in a cargo hold, and to load ballast even in a heavy bulk cargo with a large specific gravity. Even in a state, a bulk carrier that easily equalizes load distribution to longitudinal strength members in the longitudinal direction of the hull is provided. In a bulk carrier, the total length is 250 m or more and 285 m or less, the mold width is 44 m or more and 49 m or less, and the cargo area is divided by a horizontal bulkhead and the maximum width Bc of each cargo hold is The ratio Bc / Lc of the maximum distance Lc in the longitudinal direction of the hull between the horizontal bulkheads is 1.40 or more and 1.65 or less. [Selection] Figure 1

Description

  The present invention relates to a bulk carrier, and more particularly to a bulk carrier that is medium-sized and that can easily equalize load distribution to a longitudinal strength member and a lateral strength member.

  Conventionally, bulk carriers are also called bulk carriers, and carry bulk cargo such as unpacked grains, ore, coal, cement, etc. in a cargo hold. In this bulk carrier, there is a case where the cargo is fixed to one kind, and a case where the cargo is changed from a light bulk cargo with a small specific gravity such as grain to a bulk cargo with a large specific gravity such as ore. When transporting this heavy bulk cargo, instead of loading heavy bulk cargo equally in all cargo holds, considering the convenience of handling and suppressing excessive drop in the center of gravity. Regular warehouse loading is carried out in the cargo hold.

  For this reason, cargo bays and bulk carriers with sufficient strength should be used for both voyages in which such a cargo is loaded in a state where all cargo holds are loaded with relatively light bulk cargo. It is required to be.

  On the other hand, the captain, ship width, draft and air draft (height from the water surface of the ship), etc. are restricted by harbors, routes, canals and the like. For this reason, there is an increasing demand for medium-sized bulk carriers that can enter a large number of ports for relatively large cargo weight and that can efficiently carry out cargo handling.

In this connection, the shipboard inner plate is disposed at a predetermined distance from the shipboard outer plate between the bottom inclined plate forming the bilge hopper tank and the upper deck on the cargo hold side of the shipboard outer plate. At the same time, a hull structure of a bulk carrier is proposed in which a top side tank is provided at the inner corner of the ship side inner plate and the upper deck, and the top side tank is configured as a fuel oil tank (see, for example, Patent Document 1).
The hull structure of such bulk carriers aims to improve safety against damage to the outer skin of the ship side and to prevent leakage of fuel oil due to damage to the outer skin of the fuel oil tank part. In terms of ship strength, the load distribution in the full load state and the ballast state can be appropriately distributed, and development of a medium-sized bulk carrier that makes it easy to use has not been considered.

JP-A-2005-231528

In the bulk carrier, the present invention aims to optimize the scale, improves the balance of load distribution between the longitudinal strength member and the lateral strength member in the cargo hold, and is also capable of loading a heavy bulk cargo with a large specific gravity. An object of the present invention is to provide a bulk carrier that can easily equalize the load distribution to the longitudinal strength members in the longitudinal direction of the hull even in the ballast state.

  In order to achieve the above object, the ship of the present invention is a bulk carrier in which the total length is 250 m or more and 285 m or less, the mold width is 44 m or more and 49 m or less, and the cargo area is divided by a horizontal bulkhead. The ratio Bc / Lc between the maximum width Bc of each cargo hold and the maximum distance Lc in the longitudinal direction between the transverse bulkheads is 1.40 or more and 1.65 or less.

  According to this configuration, the conventional bulk carrier is divided into two categories: a total length of 240 m or less and a category of about 290 m. In the present invention, the total length is 250 m or more and 285 m or less. It can be an easy-to-use bulk carrier that has a large loading weight and is medium in size and can enter many ports.

  At the same time, the ratio Bc / Lc between the maximum width Bc of each cargo hold and the maximum distance Lc in the longitudinal direction of the hull between the horizontal bulkheads is 1.40 or more and 1.65 or less. Both can share the strength of the cargo hold in a well-balanced manner, and can be a bulk carrier with a good balance between longitudinal strength and lateral strength.

  Also, in the above bulk carrier, if the number of cargo holds is an odd number in the longitudinal direction of the hull, this configuration makes it possible to empty the cargo hold when loading heavy bulk cargo with high specific gravity such as ore. Every other cargo is loaded into the cargo hold, but in the case of an odd number, it can be loaded into the first and last cargo hold and the cargo hold can be used effectively, and load distribution in the longitudinal direction of the hull. Can be arranged in a well-balanced manner, the load of the longitudinal strength member can be equalized, and trim adjustment is facilitated.

  In the above bulk carrier, if the width of the hatch cover of the cargo hold is configured to be 30% or more and less than 50% of the mold width of the bulk carrier, the size of the hatch opening in the upper deck is reduced. Therefore, it becomes easy to maintain the strength of the upper deck.

  The bulk carrier according to the present invention can optimize the scale, improve the balance of load distribution between the longitudinal strength member and the lateral strength member in the cargo hold, and can also load a ballast even in a heavy bulk cargo loaded with a large specific gravity. Even in the state, it is possible to easily equalize the load distribution to the longitudinal strength members in the longitudinal direction of the hull.

1 is a side sectional view schematically showing a configuration of a ship according to an embodiment of the present invention. FIG. 2 is a plan layout view on the upper deck of the ship of FIG. 1. It is front sectional drawing in the cargo hold of the ship of FIG. FIG. 2 is a partially enlarged side sectional view in which a central portion of FIG. 1 is enlarged. It is the elements on larger scale which expanded the center part of FIG. It is a sectional side view which shows the structure of the horizontal partition of the 1st structure of the cargo hold forward or back rather than the center part of the ship of FIG. It is a sectional side view which shows the structure of the horizontal partition of the 2nd structure of the cargo hold of the center part of the ship of FIG. It is the partial expanded side sectional view which expanded the stern side of FIG. It is the elements on larger scale which expanded the stern side of FIG. It is front sectional drawing in the position of the fuel tank of the ship of FIG.

Hereinafter, a bulk carrier according to an embodiment of the present invention will be described with reference to the drawings. The bulk carrier 1 according to the embodiment of the present invention is a bulk carrier that may carry bulk cargoes having a relatively large specific gravity such as coal and ore.

  In the bulk carrier 1 of the embodiment shown in FIGS. 1 to 3, a hull is formed surrounded by the upper deck 2, the ship side outer plate 3, and the ship bottom 4, and on the stern side, the engine room 6, the propeller 7, and the rudder 8. And are provided. Further, an upper structure 9 including a bridge, a residential area, a chimney, a bridge wing portion 9a, and the like is provided above the engine room 6.

  The bulk carrier 1 has a total length Lo shown in FIG. 1 of 250 m or more and 285 m or less, preferably 260 m or more and 280 m or less, and a mold width Bm shown in FIGS. 2 and 3 is 44 m or more and 49 m or less, preferably Is configured as a medium-sized bulk carrier with a length of 44.5 m or more and 48 m or less.

  According to this configuration, the conventional bulk carrier is divided into a total length of 240 m or less and a category of around 290 m. In the present invention, the total length Lo is 250 m or more and 285 m or less, preferably 260 m or more. And by setting it as 280 m or less, it can be set as the easy-to-use bulk carrier which has a comparatively large cargo weight and can enter many ports at medium scale.

  In this embodiment, the bulk carrier 1 is configured as a valveless hull form without a bow valve. Further, with respect to the hull longitudinal direction X, the position of the rear end of the bridge wing portion 9a is based on the position of the stern side intersection of the side flat line and the upper deck side line that are the boundary line between the flat surface portion and the curved surface portion on the ship side of the hull. Is also configured to be forward. That is, with respect to the hull longitudinal direction X, the deck line is configured to have a full width at the position of the rear end of the bridge wing portion 9a.

  Furthermore, the ratio (d / D) of the full draft D and the mold depth D as shown in FIG. 3 is 0.74 or less, preferably 0.71 or less. As a result, it is possible to secure the appropriate height of the freeboard f when carrying cargo having a relatively large specific gravity such as coal or ore.

  And in this invention, as shown in FIG.4 and FIG.5, the hull front-back direction X between the maximum width Bc of each cargo hold 10 which divided the cargo division of the bulk carrier 1 by the horizontal bulkhead 12, and the horizontal bulkhead 12 is shown. The ratio Bc / Lc of the maximum distance Lc is 1.40 or more and 1.65 or less, preferably 1.45 or more and 1.60 or less. Here, the maximum distance Lc is the distance from the rear end of the horizontal partition 12 to the rear end of the adjacent horizontal partition 12 at the center of the height of the horizontal partition 12.

  According to this configuration, the ratio Bc / Lc of the maximum width Bc of each cargo hold and the maximum distance Lc in the longitudinal direction between the horizontal bulkheads is 1.40 or more and 1.65 or less, preferably 1.45 or more and Since it is 1.60 or less, the load to the cargo hold 10 can be shared in a balanced manner by both the longitudinal strength member and the lateral strength member, and it becomes a bulk carrier with a good balance between the longitudinal strength and the lateral strength. It can be made more appropriate.

  That is, in a cargo hold where the maximum distance Lc is relatively short compared to the maximum width Bc where the ratio Bc / Lc exceeds 1.65, the strength is mainly handled by a double bottom vertical strength member. In order to maintain the strength of the storage 10, it is necessary to strengthen the longitudinal strength member. On the other hand, in a cargo hold where the maximum distance Lc where the ratio Bc / Lc is less than 1.40 is relatively long compared to the maximum width Bc, the strength is handled by the lateral strength member, and in order to maintain the strength of the cargo hold. It is necessary to strengthen the double-bottom lateral strength member. In other words, in each case, the strength distribution for the longitudinal strength member and the lateral strength member is biased.

  Further, when the number Nc of cargo holds 10 is set to an odd number in the longitudinal direction X of the hull, when ores having a large specific gravity are transported, the cargo holds between them are emptied and the ores etc. Can be loaded into the cargo hold 10 at the front (NO. 1 in FIG. 1) and the cargo hold 10 at the rear (NO. 7 in FIG. 1). The load distribution in the hull longitudinal direction X of the bulk carrier 1 can be arranged in a more balanced manner than when the number Nc of the holds 10 is an even number, and the load of the longitudinal strength member can be equalized. Further, the trim (vertical inclination with respect to the hull longitudinal direction X) can be easily adjusted.

  In this medium-sized bulk carrier 1, the number Nc of cargo holds 10 is preferably 7 out of odd numbers, and the ratio Bc / Lc in the cargo hold 10 within the above range Lo is within the above range. Easy to configure. Further, when the number Nc of the cargo holds 10 is 5, not only the maximum distance Lc becomes too large, but also the cargo holds 10 and the hatch covers 11 become too large, making it difficult to manufacture the hatch covers 11. On the other hand, when the number Nc of the cargo holds 10 is 9, the maximum distance Lc becomes too small.

  Further, as shown in FIG. 3, in the bulk carrier 1, the ship side outer plate 3 on the side surface side of the cargo hold 10, the bottom plate 17 on the ship bottom side, the bottom side tank 15 on the lower side, and the top side tank 16 on the upper side The ship side skin 3 has a single ship side structure. And in this top side tank 16, the lower side of the inclination board 16a is bent and the horizontal part 16b is provided.

  In addition, as shown in FIG. 3, when the width Bh of the hatch cover 11 of the cargo hold 10 is set to be 30% or more and less than 50% of the mold width Bm of the bulk carrier 1, the hatch in the upper deck 2 Since the magnitude | size of the opening part 2a becomes small, it becomes easy to maintain the intensity | strength in the upper deck 2. FIG. The hatch cover 11 moves on the hatch cover rail 11a to open the hatch opening 2a. 3 and 10, the hatch cover rail 11a is omitted and not shown.

  Further, as shown in FIGS. 6 and 7, a horizontal partition wall 12 that partitions the cargo hold 10 includes a corrugated plate (corrugated partition wall) 12a, a lower earth tool 12b disposed at the lower end of the corrugated plate 12a, and the corrugated plate. And an upper stool 12c disposed at the upper end of 12a.

  Then, as shown in FIG. 6, the lower tool 12b of the transverse bulkhead 12 is formed so that the lower end side extends forward in the hull longitudinal direction X, and the front position P1 of the lower end of the lower tool 12b is the lower end of the corrugated plate 12a. It is set as the structure located ahead in the hull front-back direction X rather than the front side position P3.

In the present invention, as shown in FIG. 7, only in the horizontal bulkheads (the horizontal bulkheads in front of No. 4 and No. 5) 12 of the cargo holds 10 in the central part of the hull of the cargo holds 10, the horizontal bulkheads. Not only the front side position P1 of the lower end of the 12 lower tools 12b but also the rear side position P2 of the lower end is positioned behind the rear side position P4 of the lower end of the corrugated plate 12a in the hull longitudinal direction X.
That is, if the lower end of the lower tool 12b stands upright with respect to the bottom plate 17 of the cargo hold, the degree of stress concentration at this intersection increases, but the lower end of the lower tool 12b is inclined with respect to the bottom plate 17 of the cargo hold. Thus, the degree of stress concentration can be reduced.

  According to this configuration, since the degree of stress concentration generated at the lower end of the transverse bulkhead 12 can be reduced even when ballast water is added to a part of the cargo hold 10 at the center of the hull, load distribution by ballast water can be reduced. It can be made more appropriate, and it becomes easy to equalize the load of the load on the longitudinal strength member in the hull longitudinal direction. Thereby, ballast water can be mounted also in a cargo hold at the time of stormy weather, and draft can be deepened and safer voyage can be implemented.

  Next, the ballast tank 30 will be described. The ballast tank 30 is disposed in the bottom side tank 15 and the top side tank 16. The number Nbb of the partition walls 31 in the hull longitudinal direction X of the ballast tank 30 is made smaller than the number Ncb of the partition walls 12 of the cargo hold 10 in the hull longitudinal direction X. That is, with respect to the hull longitudinal direction X, the number Nb of the ballast tanks 30 with respect to the full length direction X of the hull in the cargo area is made smaller than the number Nc of the cargo holds 10. Thereby, systems, such as a ballast piping to the ballast tank 30, can be simplified, and also the partition wall 31 of the ballast tank 30 is reduced, and the weight can be reduced.

  For example, when the number Nc of cargo holds 10 is 7, as shown in FIG. 1 cargo hold is used as it is as one section of ballast tank 30, and NO. 2 cargo hold 10 and NO. No. 3 cargo hold 10 part, NO. 4 cargo hold 10 and NO. No. 5 cargo hold 10 part, NO. 6 cargo hold 10 and NO. Each of the two sections of the 7 cargo hold 10 is a ballast tank 30. As a result, with respect to the hull longitudinal direction X, the number Nb of the ballast tanks 30 is 4 with respect to 7 of the number Nc of the cargo holds 10.

  As shown in FIGS. 3 and 10, when the duct keel 4a is provided at the center of the ship bottom, a ballast pipe (not shown) communicating with the ballast tank 30 is arranged inside the duct keel 4a. Will be able to. Thereby, since it is not necessary to arrange the ballast pipe in the ballast tank, maintenance can be performed even when the ballast tank is filled with water, and the corrosion of the ballast pipe can be prevented and the maintenance of the ballast pipe can be simplified.

  Further, as shown in FIGS. 8 to 10, the fuel tank (cross hatched portion) 40 is provided at the position of the top side tank 16. With this configuration, the fuel tank 40 is easily separated from the ship-side outer plate 3 so that fuel does not flow out in the event of an accident, and a double side configuration can be easily adopted. Further, by using part of the void space 40a on the ship side of the fuel tank 40 and the ballast tank 30 as a reservoir tank for rainwater / deck washing water, etc., it is possible to prevent sewage outflow from the ship.

  In this fuel tank 40, a void space (gap) 40 a or a ballast tank (shaded hatched portion) 30 is provided on the ship side with the ship side skin 3, that is, the ship side has a double structure, It is configured not to directly contact the ship side skin 3 so that fuel leakage to the outside does not occur even in the event of an accident such as a collision.

  Regarding the arrangement of the fuel tank 40 in the longitudinal direction X of the ship, for example, in the configurations of FIGS. 7 cargo hold 10 and engine room 6.

  According to the bulk carrier 1 configured as described above, the scale can be optimized, the load distribution between the longitudinal strength member and the lateral strength member in the cargo hold 10 can be improved, and a heavy bulk cargo having a large specific gravity can be obtained. The load distribution to the longitudinal strength members in the longitudinal direction of the hull can be easily equalized in both the loaded state and the ballast state.

DESCRIPTION OF SYMBOLS 1 Bulk carrier 2 Upper deck 2a Hatch opening 3 Ship side outer plate 4 Ship bottom 4a Duct keel 9a Bridge wing part 10 Cargo hold 11 Hatch cover 12 Lateral bulkhead 12a Corrugated plate 12b Lower earth tool 16 Top side tank 16a Inclined plate 16b Horizontal part 17 Cargo hold bottom plate 30 Ballast tank 31 Ballast tank partition wall 40 in the longitudinal direction Fuel tank 40a Void space Lo Total length B1 Corrugated plate width in the longitudinal direction B2 Lower width of the lower tool B2 in the longitudinal direction of the hull B2f Lower end of the lower tool Overhang B2a Overhang to the rear of the lower end of the lower tool Bm Mold width Bc Maximum cargo hold width Bh Hatch cover width d Full draft D Type depth Lc Maximum cargo hold distance P1 Front of lower tool lower end Position P2 Under the lower tool Side position X hull longitudinal direction after the lower end of the front position P4 corrugated plate of the lower end of the side position P3 corrugated plates after

Claims (3)

  In the bulk carrier, the total length is 250 m or more and 285 m or less, the mold width is 44 m or more and 49 m or less, and the cargo area is divided by the horizontal bulkhead between each maximum cargo width Bc and the horizontal bulkhead. A bulk carrier in which the ratio Bc / Lc of the maximum distance Lc in the longitudinal direction of the hull is 1.40 or more and 1.65 or less.   The bulk carrier according to claim 1, wherein the number of the cargo holds is an odd number in the longitudinal direction of the hull.   The bulk carrier according to claim 1 or 2, wherein a width of a hatch cover of the cargo hold is 30% or more and less than 50% of a mold width of the bulk carrier.

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