JP2002362473A - Bow structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bow structure capable of preventing water ingress into a fore peak tank even when a ship bottom is subjected to a raking damage, and suppressing the inclination of a hull and reduction of the stability performance. SOLUTION: A double bottom 2 is provided in a bow part partitioned by a collision bulkhead, an upper part of the double bottom forms the fore peak tank 4, and a lower part of the double bottom forms a void or a protection tank 5'. Even when the ship bottom is subjected to the raking damage, water ingress is stopped by the void 5 or the protection tank 5', and no water ingress occurs in the fore peak tank 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bow structure capable of providing sufficient stability even when a bottom of a ship suffers from a raking damage (a bottom tear).

[0002]

2. Description of the Related Art Conventionally, when a ship is damaged by grounding or the like, a watertight bulkhead separating the hull is provided so that the entire hull is not flooded. Stipulated by regulations.

[0003] For this reason, a bow bulkhead is provided to divide the bow part, and this part is used as a forepeak tank for injecting and discharging ballast water. There is flooding, and the hull inclines greatly forward in the longitudinal direction of the hull, and in some cases this incline may promote inundation of other undamaged tanks, and in the worst case may result in sinking .

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a bow structure capable of preventing ingress of water into a fore peak tank and suppressing a decrease in stability of a hull even when the bottom of the hull suffers from rake damage. Aim.

[0005]

In the bow structure, a double bottom is provided at a bow part separated by a bow bulkhead, a lower portion of the double bottom is vacant, and a separation is performed by the double bottom. The upper part of the bottom of the heavy ship is configured as a fore peak tank.

[0006] In the same bow structure, a double bottom is provided at the bow separated by a bow bulkhead, the lower part of the double bottom is used as a defense tank, separated by the double bottom, and the upper part of the double bottom is formed. It is configured as a fore peak tank.

In addition, a communication valve is provided between the security tank and the forepeak tank, and the security tank and the forepeak tank can be communicated via the communication valve. Further, the opening of the communication valve is synchronized with the opening of the ballast water injection / drainage valve of the fore peak tank.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view schematically showing a bow structure according to the present invention, FIG. 2 is a side view showing another example of the bow structure, and FIG. 3 is a side view showing still another example of the bow structure. .

Reference numeral 1 denotes a hull, which shows only a bow portion. Reference numeral 2 denotes a bow bulkhead provided at the bow from the bottom to the upper deck in the transverse section of the hull 1. Reference numeral 3 denotes a double bottom provided at the bottom of the bow, which is provided so as to further partition the bow divided by the bulkhead 2 into a bottom and an upper part.

Reference numeral 4 denotes a forepeak tank which is formed on the upper part of the double bottom 3 at the bow section separated by the bulkhead 2, and is used as a ballast tank. Numeral 5 is a lower portion of the double bottom 3 at the bow portion which is separated by the bulkhead 2, which is configured as a space completely separated from the fore peak tank 4 by the double bottom 3 in the example shown in FIG. Have been.

In the example shown in FIG. 2 and FIG.
The lower part of the double bottom 3 of the bow section demarcated by is formed as a defense tank 5 '. In FIG. 3, reference numeral 6 denotes a communication valve provided on the double bottom 3, and the defense tank 5 ′ and the forepeak tank 4 can communicate with each other via the communication valve 6. As the communication valve 6, a valve such as a surface valve or a butterfly valve that can reliably open and close under pressure is used.

Reference numeral 7 denotes a ballast water injection / discharge pipe, and reference numeral 8 denotes a ballast water injection / discharge valve provided in the pipe 7. In the example of FIGS. 2 and 3, a ballast water injection / discharge line 7 and a valve 8 are provided in a defense tank 5 ′ formed below the double bottom 3.
Is provided. That is, the defense tank 5 'is also used as a ballast tank.

In the examples shown in FIGS. 2 and 3, since the protection tank 5 'is constructed, fittings as a tank are added, but a sufficient ballast capacity can be secured. In addition, in the example shown in FIG. 3, when injecting and draining ballast water, the defense tank 5 ′ and the forepeak tank 4 are communicated by the communication valve 6, and are performed by one pipe 7 and valve 8. Thus, the operation can be treated as a single tank.

In this case, when the ballast water is injected / discharged, that is, when the ballast water injection / discharge valve 8 is opened, the communication valve 6 is also opened. That is, the opening of the communication valve 6 is synchronized with the opening of the ballast water injection / discharge valve 8. Therefore, the communication between the defense tank 5 'and the forepeak tank 4 is as follows.
The communication valve 6 keeps the closed state only when the ballast water is discharged and discharged, and when the ballast water is not discharged and discharged.

Conventionally, cargo tanks have a double bottom structure so that cargo does not flow out when damaged, but the bow is not loaded because it is not loaded.
There is no double bottom structure. In the present invention, the double bottom 3 is provided at the bow. Regarding the depth of the double bottom 3, since the requirement for the depth of the double bottom of the cargo tank described above is stipulated in the International Convention on the Prevention of Marine Pollution,
So to the depth requirements.

With this configuration, even when the bottom of the ship suffers a raking damage, the flooding stops in the empty space 5 or the defense tank 5 'below the double bottom 3 and does not flood the forepeak tank 4. In the above, the configuration of the bow was explained.In recent years, there are ships that follow the ice sea area, and in the ice sea area, there are ships that move backward while breaking ice at the stern. Configuration.

[0017]

According to the present invention, a double bottom is provided at the bow part separated by a bulkhead, the upper part of the double bottom is used as a forepeak tank, and the lower part of the double bottom is used as an empty space or defense tank. Even in the event of raking damage, flooding will remain in voids or defense tanks and will not flood the forepeak tank.

Therefore, the hull is prevented from tilting greatly in the front-rear direction, and it is also prevented that the hull tilts to promote inundation in other undamaged sections, and the hull's stability is improved. Can be suppressed from decreasing.

[Brief description of the drawings]

FIG. 1 is a side view schematically showing a bow structure according to the present invention.

FIG. 2 is a side view showing another example of the bow structure.

FIG. 3 is a side view showing still another example of the bow structure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Hull 2 Bow bulkhead 3 Bow double bottom 4 Fore peak tank 5 Vacancy 5 'defense tank 6 Communication valve 7 Ballast water injection / discharge valve 8 Ballast water injection / discharge valve

Claims (4)

[Claims] (1) A double bottom is provided at a bow portion separated by a bow bulkhead, a lower portion of the double bottom is vacant, and an upper portion of the double bottom is configured as a fore peak tank separated by the double bottom. The bow structure characterized by: 2. A double bottom is provided at a bow part separated by a bow bulkhead, a lower part of the double bottom is used as a defense tank, and an upper part of the double bottom is configured as a fore peak tank separated by the double bottom. The bow structure characterized by: 3. The bow structure according to claim 2, wherein a communication valve is provided between the defense tank and the forepeak tank, and the defense tank and the forepeak tank can be communicated via the communication valve. . 4. The bow structure according to claim 3, wherein the opening of the communication valve and the opening of the valve for discharging and discharging ballast water are synchronized.