JP4536677B2 - Structure of water ballast tank and water filling method in a ship. - Google Patents

Description

  The present invention relates to a structure of a water ballast tank in a ship and a water ballasting method for the water ballast in the tank, and in particular, a structure of a water ballast tank that injects a water ballast excluding mud sand into a double bottom water ballast tank. And the water-balling method for the water ballast tank.

In the ship, a double bottom structure is adopted, and the void portion of the double bottom is used as a water ballast tank. In some cases, the side wall portion is also a double wall and a water ballast tank is formed on the side portion. Usually, the water drained into these water ballast tanks is poured and drained through a water drainage pipe provided in the double bottom water ballast tank (see, for example, Patent Document 1).
The double bottom water ballast tank is integrated with a cargo tank above the inner bottom plate and is divided into a plurality of sections in the longitudinal direction of the hull. A branch pipe is provided for each section from the pouring pipe.

  Seawater sucked from the pump is poured into the double bottom water ballast tank through the pouring / draining pipe as a water ballast, and is filled with water. At this time, if the water ballast is sucked up at a shallow draft port, the water ballast mixed with mud sand may be sucked up. It will be in the state which accumulates in the bottom part of a ballast tank.

Even when the water ballast is drained at the time of loading, the accumulated mud sand is difficult to flow out and often remains deposited. If mud sand remains accumulated in the water ballast tank in this way, the loading capacity of the ship is reduced by the weight of the accumulated mud sand, and the loading efficiency is lowered.
Therefore, in order to prevent such a reduction in loading efficiency, it is necessary to remove the accumulated mud sand in the water ballast tank, and the sediment mud sand is discharged regularly.

  However, on the inner surface of the outer plate that forms the double bottom of the ship, vertical and horizontal reinforcing materials such as longages and floor materials are arranged in a lattice shape and are partitioned. In order to remove the muddy sand accumulated between the reinforcing materials, all the sections are manually operated.

  For example, the entire double bottom water ballast tank of a large tanker has a length of about 260 m × width of about 60 m, each section is about 3 m to 6 m × width is about 0.8 to 0.9 m, and the total number of sections is 3 1,000 to 6,000 sections. As described above, the work for removing mud sand manually from a huge area over a wide area is laborious, time consuming and costly, and is extremely inefficient.

  When water ballast is drained, the water is absorbed and discharged from the bell mouth attached to the branch pipe of the pouring / draining pipe. The bell mouth is disposed in a certain section partitioned by the reinforcing material in a lattice shape. Therefore, when the water level falls below the height of the reinforcing material, the water course is formed so that the water ballast in each section flows toward the section where the bell mouth is disposed.

  This water course is formed by a drain hole in the lower end of the vertical and horizontal reinforcements, but if there is a lot of mud sand in the double bottom water ballast tank, the water course may not be formed as planned. In severe cases, the accumulated mud sand blocks the drain hole and the water course may not be formed.

Japanese Patent Laid-Open No. 5-77781 (2nd page, FIG. 1)

  The present invention solves the problems as described above, and deposits mud sand in a limited narrow area, and pours water ballast with low mud sand contamination into the double bottom water ballast tank. It is an object of the present invention to obtain a water ballast tank structure and a watering method for the water ballast tank in a ship that can efficiently and easily remove mud sand.

This is a water ballast tank structure for ships with a double bottom water ballast tank, which forms a water ballast tank for silt that is separated watertight from the double bottom water ballast tank, and one end of the water ballast for silt. A water conduit that opens in the upper layer of the tank and opens in the double-bottomed water ballast tank at the other end is connected to the double-bottomed water ballast tank and the silt ballast tank, and the water ballast is connected to the silt ballast tank. Water was poured into the silt ballast tank, and the water ballast in the upper part of the silt water ballast tank was poured into the double-bottom water ballast tank from the water conduit to make it water-filled . .

  In this water ballast tank structure, the bottom surface of the silt water ballast tank is flattened, and the double bottom water ballast tank and the inner bottom of the silt water ballast tank are provided with drainage pipes. A ship connected to the water injection and drainage pipe provided in the bottom water ballast tank through a valve and provided with a branch pipe that opens into the silt water ballast tank. The side void was formed in the silt water ballast tank.

  Furthermore, a silt water ballast tank is divided into a plurality of sections, and a water conduit is provided to connect the upper layer part and the lower layer part of the adjacent section in order from the section into which the water ballast is introduced, and in the double bottom water ballast tank. And a pouring / draining pipe opened in the silt water ballast tank is connected via a connecting pipe having a valve inserted therein.

  Also, a water ballast tank watering method for a ship having a double bottom portion as a water ballast tank, which forms a silt water ballast tank that is partitioned watertight from the double bottom water ballast tank, and sinks one end. Open the upper part of the mud water ballast tank and provide a water conduit that opens the other end into the double-bottomed water ballast tank, inject the water ballast into the silt ballast tank, and place it in the silt ballast tank. The mud sand was allowed to settle, and the water ballast at the upper layer of the silt water ballast tank was poured into the double bottom water ballast tank to make it hydrated.

  In this water ballast watering method, water ballast once poured into the double-bottomed water ballast tank is absorbed by a pump from a drainage pipe that opens through a branch pipe into the double-bottomed water ballast tank. It is also characterized in that the water ballast is circulated between the double-bottomed water ballast tank and the silt water ballast tank by supplying it to a pouring drainage pipe opened through a branch pipe in the water ballast tank.

  A double bottom water ballast tank and a silt water ballast tank are formed that are water-tightly partitioned. One end is opened in the upper layer of the silt water ballast tank and the other end is opened in the double bottom water ballast tank. A water conduit is installed, water ballast is poured into the silt ballast tank, mud sand is settled in the silt ballast tank, and the water ballast at the upper layer of the silt water ballast tank is turned into a double bottom water ballast tank. Since the water was poured and the water was added, it was possible to deposit a new type of mud sand in the water ballast tank for siltation, and the double-bottomed water ballast tank can be filled with water ballast with less mud sand. As a result, mud sand can be discharged from a narrow silt water ballast tank, so that mud sand discharge work can be performed efficiently and easily. In addition, the water course in the double bottom water ballast tank is no longer adversely affected.

  The best mode of the present invention shown in the drawings will be described below. FIG. 1 is a front sectional view showing a schematic configuration of a water ballast tank in a ship according to the present invention, FIG. 2 is a front sectional view showing a schematic configuration of a water ballast tank having a different pouring method, and FIG. 3 is a diagram of a water ballast tank having a different structure. It is a front sectional view showing a schematic configuration. 4 is a schematic side sectional view showing an example of a cascade type silt water ballast tank, FIG. 5 is a developed plan view of the configuration shown in FIG. 1, and FIG. 6 is a developed plan view of the configuration shown in FIG.

First, the outline of the water ballast tank will be described with reference to FIG. FIG. 1 shows an example in which the side wall portion also has a double structure, and the void portion of the double side wall portion is also formed in the water ballast tank.
The hull 1 has a double hull structure with an outer plate 2, an inner bottom plate 3 and an inner plate 4, and a double bottom water ballast tank 5 is formed between the outer plate 2 and the inner bottom plate 3. .
Further, a silt water ballast tank 6 having a bottom plate 7 is formed between the outer plate 2 and the inner plate 4 so as to be positioned above the double bottom water ballast tank 5. The connecting portion between the double bottom water ballast tank 5 and the silt water ballast tank 6 is kept watertight by a bottom plate 7.

  The double bottom water ballast tank 5, the silt water ballast tank 6 and the tank 6 have one end opened to the upper layer of the silt water ballast tank 6 and the other end opened to the double bottom water ballast tank 5. 8 is communicated. The water conduit 8 is constituted by a pipe, a trunk, or the like.

  The double bottom water ballast tank 5 is provided with a pouring / draining pipe 9 having a branch pipe 9 'provided with a bell mouth B and an opening / closing valve V for each section in the length direction. In addition, a pouring / draining pipe 10 having a branch pipe 10 ′ having a bell mouth B and an on-off valve V is provided for each section in the ship length direction in the lower part of the silt water ballast tank 6. Note that the pouring / draining pipe 10 may be disposed in the double bottom water ballast tank 5 and the branch pipe 10 ′ may be opened through the silt water ballast tank 6 because of the arrangement space. In the figure, reference numeral 11 denotes a longitudinal partition wall vertically passing through the center of the hull 1, and 12 denotes a longage attached to the inner surface of the outer plate 2 in the longitudinal direction.

In the example shown in FIG. 2, a double drain water ballast tank 5 is connected to a pouring / draining pipe 9 via an on-off valve V and connected to a bell mouth B disposed in the lower layer portion of the silt water ballast tank 6. A branch pipe 13 is provided.
In the example shown in FIG. 1 and FIG. 2, the upper surface of the bottom plate 7 at the connecting portion between the double bottom water ballast tank 5 and the silt water ballast tank 6, that is, the inner bottom surface of the silt water ballast tank 6 is reinforced. It is formed on a flat inner bottom without attaching any material.

  The structure shown in FIG. 3 is located on the side of the double bottom water ballast tank 5, and a silt water ballast tank 6 having a vertical partition plate 14 is formed between the outer plate 2 and the inner bottom plate 3. ing. The connecting portion between the double bottom water ballast tank 5 and the silt water ballast tank 6 is kept watertight by a vertical partition plate 14.

  As shown in FIG. 4, a horizontal partition plate 15 is provided, and the silt water ballast tank 6 is partitioned into a plurality of stages in the vertical direction (captain direction), and the bell mouth B is disposed in the lower layer in the partition portion on the front side (stern side). In addition, in order from the partition portion where the bell mouth B is disposed, the adjacent conduits are opened at one end at the upper layer portion of the front partition portion, and the water guide pipe 16 is opened at the lower layer portion at the adjacent partition portion. A cascade tank structure can be used. In this case, a bell mouth dedicated to drainage can be disposed in the adjacent partition portion.

FIG. 5 is a plan view of the configuration of FIG. 1, in which the water ballast absorbed through the sea chest 18 and the water absorption pipe 19 is supplied to the water injection / drainage pipe 10 by the pump 17, and branches provided in the water injection / drainage pipe 10 are provided. Water is poured from the pipe 10 ′ into the silt water ballast tank 6, water is poured from the silt water ballast tank 6 into the double bottom water ballast tank 5 through the water conduit 8, and water is poured into the double water tower by the pump 17. 9 shows a line through which the water ballast of the silt water ballast tank 6 is discharged from the discharge pipe 21 via the double bottom water ballast tank 5 and the pouring / draining pipe 10.

When water is poured in this line, the on-off valves V1, V2, V3 provided on the water suction pipe 19, the on-off valves V5, V9 provided on the pouring / draining pipe 10 and the electromagnetic switching provided on the branch pipe 10 'of the pouring / draining pipe 10 The valve V11 is opened, the on-off valves V4 and V8 provided on the pouring drain pipe 9, the on-off valve V6 provided on the drain pipe 21, and the on-off valve V7 provided on the connecting pipe 20 between the pouring drain pipe 9 and the pouring drain pipe 10. And the on-off valve V10 provided in the branch pipe 9 'of the pouring / draining pipe 9 is closed.
When the pump 17 is operated in this state, the water ballast sucked from the sea chest 18 while preventing the entry of suspended matter or the like is supplied from the pump 17 to the pouring / drainage pipe 10 and is made from the branch pipe 10 'to the silt water ballast. Water is poured into the tank 6.

  When the water level in the silt water ballast tank 6 rises, the water ballast flows into the water conduit 8 that opens to the upper layer of the silt water ballast tank 6 and is poured into the double bottom water ballast tank 5. become. At this time, coarse mud sand having a large specific gravity mixed in the water ballast settles in the silt water ballast tank 6, and the double bottom water ballast tank 5 is less contaminated with mud sand in the silt water ballast tank 6. Upper water will be poured.

  When discharging the water ballast, if the on-off valves V2, V3, V4, V6, V7, V8, V9 and the electromagnetic on-off valves V10, V11 are opened and the on-off valves V1, V5 are closed and the pump 17 is operated, the double bottom The water ballast in the water ballast tank 5 and the silt water ballast tank 6 is absorbed by the pump 17 from the pouring drain pipe 9 and the pouring drain pipe 10, and is discharged from the drain pipe 21 through the on-off valve V6 to the outside of the ship. The water ballast may be discharged from the sea chest 18 through the water absorption pipe 19.

  When discharging the water ballast as described above, if the on-off valve V7 is opened and the V8 is closed, the discharge from the silt water ballast tank 6 can be performed with priority, and then the on-off valve V8 is opened. If V7 is closed, the double bottom water ballast tank 5 can be discharged. Therefore, it is possible to start the work of discharging the accumulated mud sand in the silt water ballast tank 6 during the discharge of the water ballast from the double bottom water ballast tank 5.

  If the on-off valves V2, V3, V4, V5, V8, V9 and the electromagnetic on-off valves V10, V11 are opened and the pump 17 is operated with the on-off valves V1, V6, V7 closed, a double bottom water ballast tank The water ballast in 5 can be supplied from the pouring drainage pipe 9 to the pouring drainage pipe 10 via the hump 17 and can be circulated and supplied to the silt water ballast tank 6. Since the silt water ballast tank 6 and the double bottom water ballast tank 5 are communicated with each other by the water conduit 8, the water ballast is used for the silt and the double bottom water ballast tank 5 during the voyage of the ship. It can be circulated between the water ballast tank 6.

By circulating the water ballast in this manner, fine mud sand having a light specific gravity mixed in the water ballast can be further precipitated in the water ballast tank 6 for siltation.
In the example shown in FIG. 5, the drainage pipe 9 has been described as being used exclusively for drainage. However, when water ballast that does not cause any problem of mixing mud sand is poured, the on-off valves V7 and V8 and the electromagnetic on-off valve are used. It is also possible to open the V10, supply water ballast to the pouring / draining pipe 9, and directly pour water into the double bottom water ballast tank 5.

  FIG. 6 is a plan view of the configuration of FIG. 2. The water ballast absorbed through the sea chest 18 and the water absorption pipe 19 is supplied to the water injection / drainage pipe 9 by the pump 17. Water is poured into the silt water ballast tank 6 from the silt water ballast tank 6 through the water conduit 8 and poured into the double bottom water ballast tank 5, and the pump 17 is filled with the drainage pipe 9. The line which discharges the water ballast of the water ballast tank 6 for siltation from the pouring drain pipe 9 through the double bottom water ballast tank 5 and the branch pipe 13 from the drain pipe 21 is shown.

When water is poured in this line, the on-off valves V1, V2, V3 provided on the water absorption pipe 19, the on-off valve V5 provided on the water drain pipe 9, and the electromagnetic on-off valve V12 provided on the branch pipe 13 from the water drain pipe 9. Is closed, and the on-off valve V6 of the drain pipe 21 and the on-off valve V4 provided on the pouring drain pipe 9 and the electromagnetic on-off valve V10 provided on the branch pipe 9 'of the pouring drain pipe 9 are closed.
When the pump 17 is operated in this state, the water ballast sucked from the sea chest 18 while preventing the entry of suspended matter or the like is supplied from the pump 17 to the pouring / drainage pipe 9 and from the branch pipe 13 to the silt water ballast tank. 6 is poured.

  When the water level in the silt water ballast tank 6 rises, the water ballast flows into the water conduit 8 opened to the upper layer of the silt water ballast tank 6, and water is poured into the double bottom water ballast tank 5 from the water conduit 8. Will be. At this time, the coarse mud sand having a large specific gravity mixed in the water ballast is settled in the silt water ballast tank 6, and the double bottom water ballast tank 5 is contaminated with mud sand in the silt water ballast tank 6. Less upper water will be poured.

  When discharging the water ballast, the on-off valves V2, V3, V4, V6 and the electromagnetic on-off valves V10, V12 are opened, and the on-off valves V1, V5 are closed. If the pump 17 is operated in this state, the water ballast in the double bottom water ballast tank 5 and the silt water ballast tank 6 is absorbed by the pump 17 from the pouring drain pipe 9 and passes through the on-off valve V6 to the drain pipe 21. Discharged from the ship.

  A strainer 22 is provided in the front stage of the pump 17 to prevent foreign matter from entering the pump 17. A check valve V13 and a throttle valve V14 are provided on the discharge side of the pump 17.

  In the above description, the double-sided void part is a silt water ballast tank, but a single-sided ship has the same configuration, that is, a limited area, and one end It is possible to implement the present invention by forming a silt water ballast tank with a double bottom water ballast tank that is watertight with a water conduit that opens to the upper layer and has multiple ends that open into the double bottom water ballast tank. Is possible.

  As described above, in the present invention, the narrow silt water ballast tank 6 is provided, the water ballast is once poured into the silt water ballast tank 6, and the silt water ballast tank 6 Since the upper layer water is poured into the double-bottomed water ballast tank 5 so as to be filled with water, mud sand mixed in the water ballast is settled in the silt water ballast tank 6. For this reason, the settled mud sand can be efficiently discharged from the silt water ballast tank 6 which is a limited zone.

If the inner bottom surface of the silt water ballast tank 6 is formed flat as shown in FIGS. 1 and 2, the mud sand can be discharged very easily.
Moreover, if water is slowly poured into the silt water ballast tank 6 and the water level in the silt water ballast tank 6 is increased over time, more mud sand is stored in the silt water ballast tank. 6 can be precipitated.
However, since the water ballast water injection speed has a balance with the unloading operation, it is difficult to precipitate most mud sand mixed in the water ballast.

  In particular, the fine mud sand having a light specific gravity enters the double bottom water ballast tank 5 while being mixed in the water ballast. Therefore, in such a case, the present invention allows the water ballast to circulate between the double-bottomed water ballast tank 5 and the silt water ballast tank 6 during navigation after the water ballast is once watered. More mud sand was allowed to settle in the silt water ballast tank 6.

  For passage to the double bottom water ballast tank 5, it is possible to provide a watertight hatch on the bottom plate 7 and the vertical partition plate 14 of the silt water ballast tank 6.

The front sectional view showing the schematic structure of the water ballast tank according to the present invention. FIG. 3 is a front sectional view showing a schematic configuration of a water ballast tank having a different drainage method. FIG. 3 is a front sectional view showing a schematic configuration of a water ballast tank having a different structure. The schematic sectional side view which shows the example of the water ballast tank for cascade type silt. The expanded top view of the structure shown in FIG. The expanded top view of the structure shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hull 2 Outer plate 3 Inner bottom plate 4 Inner plate 5 Double bottom water ballast tank 6 Silt water ballast tank 7 Bottom plate 8 Water conduit 9 Inlet / drain pipe 10 Inject / drain pipe 11 Longitudinal partition wall 12 Longi 13 Branch pipe 14 Vertical partition Plate 15 Horizontal partition plate 16 Water guide pipe 17 Pump 18 Sea chest 19 Water intake pipe 20 Connection pipe 21 Discharge pipe B Bell mouth V valve

Claims (9)

Formed with a double-bottomed water ballast tank, it forms a water ballast tank for silt with a narrow bottom surface, one end is opened in the upper part of the water ballast tank for silt, and the other is a double-bottom water ballast tank A water conduit that opens inside is connected to communicate the double bottom water ballast tank and the silt ballast tank ,
Water ballast is once poured into the silt ballast tank, and mud sand is precipitated in the silt ballast tank, and the water ballast at the upper layer of the silt water ballast tank is poured into the double bottom water ballast tank from the water conduit. The structure of a water ballast tank in a ship, characterized by being inflated .   2. The structure of a water ballast tank in a ship according to claim 1, wherein the inner bottom surface of the silt water ballast tank is formed flat. The structure of a water ballast tank in a ship according to claim 1 or 2, wherein a water drainage pipe is provided in the double bottom water ballast tank and in the inner bottom portion of the silt water ballast tank. Is connected to the note drain pipe provided in the double bottom water ballast tank, the vessel according to claim 1 or claim 2, characterized in that a branch pipe opening into silt for water ballast tank Water ballast tank structure. 2. The drainage pipe provided in the double bottom water ballast tank and the drainage pipe provided in the silt water ballast tank are connected through a connecting pipe having a valve inserted therein. The structure of the water ballast tank in the ship as described in any one of -3. The water ballast tank for siltation according to any one of claims 1 to 5, wherein a water ballast tank for siltation is formed in a side void portion of the ship partitioned by an outer plate and an inner plate. Construction. The water ballast tank for siltation is divided into a plurality of sections, and a water guide pipe is provided to communicate the upper layer part and the lower layer part of the adjacent section in order from the section into which the water ballast is introduced . The structure of the water ballast tank in the ship as described in any one of Claims .   Formed with a double-bottomed water ballast tank, it forms a water ballast tank for silt with a narrow bottom surface, one end is opened in the upper part of the water ballast tank for silt, and the other is a double-bottom water ballast tank A water conduit is opened in the water, and water ballast is poured into the silt ballast tank, mud sand is precipitated in the silt ballast tank, and the water ballast in the upper layer of the silt water ballast tank is double-bottomed. A water ballast tank watering method in a ship, characterized in that water is poured into a water ballast tank.   Water ballast once poured into the double-bottomed water ballast tank is absorbed by a pump from a drainage pipe provided in the double-bottomed water ballast tank, and supplied to the pouring drainage pipe provided in the silt water ballast tank. The water-ballasting method for a water ballast tank in a ship according to claim 8, wherein the water ballast tank is circulated between the double bottom water ballast tank and the silt water ballast tank.

Images