JP2018176900A - Ship - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ship capable of securing the size of fuel tank and sucking ability of fuel while securing a view from the bridge.SOLUTION: The ship comprises a hull 10, a bridge arranged on the top of the stern side of the hull 10, a main engine 40 installed in the hull 10, a fuel tank 50 installed at the bow side of the bridge on an upper deck 13 of the hull 10, for the fuel storage of the main engine and with the outer peripheral surface extending along a down-inclined axis O toward the bow side, and a fuel suction pump 70 the suction port of which is arranged at the bow side in the fuel tank 50.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a ship.

  As a carrier ship as a kind of ship, a carrier ship is known in which a plurality of cargo tanks for storing liquefied gas such as LNG are arranged in the ship's direction (see, for example, Patent Documents 1 and 2). The plurality of cargo tanks are spherical tanks having a spherical shape. The spherical tank is provided on the bow side of the bridge provided on the stern side of the ship so that the upper half projects from the upper deck.

  In the carriers of Patent Literatures 1 and 2, the height of the spherical tank disposed on the bow side among the plurality of spherical tanks arranged in the ship's forward direction so as to ensure visibility from the bridge to the front water surface. An arrangement is disclosed that is smaller than a spherical tank located aft.

Japanese Patent Application Laid-Open No. 9-24891 Japanese Patent Application Laid-Open No. 61-241293

  By the way, in the above-mentioned carrier ship, it is also possible to use the liquid gas of the cargo tank as cargo as it is as the fuel of the main engine of the ship. However, due to the request to separate cargo and fuel, a fuel tank for storing fuel may be installed separately from the cargo tank for storing liquefied gas.

  It is desirable that such a fuel tank be made as large as possible in order to secure the cruising distance of the ship. In addition, since it is necessary to install the fuel tank in a limited space in the ship, the installation position of the fuel tank and the size of the fuel tank are limited.

  In particular, depending on the location of the fuel tank, the view from the bridge to the water surface may be obstructed. On the other hand, in order to pump out the fuel in the fuel tank appropriately by the pump, it is also necessary to pay attention to the attitude of the fuel tank in order to secure the liquid level of the fuel at the pump installation position in the fuel tank. is there.

  The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a ship capable of ensuring the size of a fuel tank and the ability to extract fuel while securing a view from a bridge. .

The present invention adopts the following means in order to solve the above problems.
That is, the ship according to one aspect of the present invention includes a hull, a bridge disposed on an upper portion on the stern side of the hull, a main aircraft provided in the hull, and the bridge on the upper deck of the hull. A fuel tank provided on the bow side, the fuel tank having an outer peripheral surface extending along an axis inclined downward toward the bow side while the fuel of the main engine is stored, and a bow side portion in the fuel tank A suction port disposed in the pump to pump out the fuel.

According to the ship of the above aspect, the outer peripheral surface of the fuel tank installed on the upper deck extends along the axis inclined downward toward the bow side. Therefore, it is possible to increase the volume of the fuel tank within the range in which the view can be secured while securing the view from the bridge to the front of the bow.
Furthermore, because the pump sucks the fuel from the bow side portion in the fuel tank which is the lower part of the inclination of the fuel tank, even when the fuel in the fuel tank becomes relatively small, the pump at the time of suction The head of the can be secured. Therefore, it can be reduced that the fuel in the fuel tank is not exhausted until the end.

  In the above aspect, it is preferable that an upper tank line and a lower tank line forming the outer peripheral surface of the fuel tank when viewed from the boat width direction are parallel to the axis.

  Since the upper tank line is inclined downward toward the bow side, it is possible to avoid obstructing the forward view of the bow from the bridge. Furthermore, since the lower tank line inclines downward toward the bow side, when the fuel in the fuel tank runs low, the fuel collects in front of the fuel tank. Therefore, the fuel collected forward can be sucked out by the pump provided on the bow side in the fuel tank.

  In the above aspect, the upper tank line extends along a visibility request line connecting the bridge and the water surface in front of the bow, as viewed in the boat width direction.

  This makes it possible to maximize the volume of the fuel tank as long as the fuel tank does not interfere with the visibility from the bridge to the front of the bow, ie, within the range in which the rules concerning the visibility of the ship do not conflict.

  In the above aspect, it is preferable that the outer peripheral surface of the fuel tank has a cylindrical surface shape centered on the axis.

  This can reduce the cost of manufacturing the fuel tank. In addition, a pressure resistant structure for storing fuel in a high pressure state can be manufactured at low cost.

  In the above aspect, the cargo hold is formed in the hull, and the cargo hold is disposed in the cargo hold and contains a liquefied gas.

  Even if a cargo tank for storing liquefied gas and a fuel tank for storing fuel are separately provided, as described above, visibility from the bridge while ensuring the maximum capacity of the fuel tank, the inside of the fuel tank Fuel consumption can be secured.

  According to the vessel of the present invention, it is possible to secure the size of the fuel tank and the ability to extract fuel while securing the visibility from the bridge.

It is a side view of the carrier according to the embodiment. It is a principal part enlarged view of FIG. It is sectional drawing orthogonal to the axis line of the fuel tank of the carrier according to the embodiment. It is a figure for demonstrating a vision requirement line. (A)-(c) is sectional drawing orthogonal to the axis line of this fuel tank which shows the modification of the fuel tank of a carrier ship.

Hereinafter, a ship 100 according to a first embodiment of the present invention will be described in detail with reference to the drawings. The ship 100 of the present embodiment is a liquefied gas carrier that transports liquefied petroleum gas (LPG) as liquefied gas.
As shown in FIG. 1, the ship 100 includes a hull 10, a bridge 20, a cargo tank 30, a main engine 40, a fuel tank 50, and a pump 70.

  The hull 10 has a weir side 11, a bottom 12 and an upper deck 13. The heel side 11 is comprised from a pair of heel side 11 outer plate which comprises the left and right heel side 11, respectively. The bottom 12 is composed of a bottom 12 outer plate connecting the left and right heel sides 11 at the lower portion.

  The upper deck 13 connects the pair of left and right heel sides 11 above the bottom 12. The upper deck 13 is an exposed deck extending from the bow to the stern. The upper deck 13 extends in the horizontal direction. Depending on the navigation state of the ship 100, the stern side of the upper deck 13 may be inclined downward as the upper deck 13 itself is lowered.

  The hull 10 has a substantially box-like cross-sectional shape orthogonal to the ship's direction, which forms a space inside, by the heel side 11, the bottom 12 and the upper deck 13. A portion on the stern side in the hull 10 is an engine room 14. A portion on the bow side of the engine room 14 in the hull 10 is a cargo hold 15 divided by the engine room 14 and a bulkhead.

  The bridge 20 is provided to extend upward from the top of the hull 10. The bridge 20 is provided on the aft side of the upper part of the hull 10 and is provided above the engine compartment 14. The bridge 20 has multiple layers. In the upper layer of the bridge 20, a control cabin 21 for operating the ship 100 is provided. The cockpit 21 is configured to be able to overlook the front of the ship 100 from a high place.

  The cargo tanks 30 are provided in the cargo hold 15 of the hull 10 so that a plurality (three in the present embodiment) are arrayed in the ship's forward direction. The part between adjacent cargo tanks 30 is provided with a partition which separates the compartment in which each cargo tank 30 is accommodated.

  The cargo tank 30 of the present embodiment is a rectangular tank configured by joining flat plate-like tank wall portions to each other. In the cargo tank 30, LPG as cargo is stored at normal pressure and low temperature. The "normal pressure low temperature state" means a state in which the liquefied state of LPG is maintained only by lowering the temperature of LPG without pressurizing it. LPG is liquefied at normal pressure by setting the temperature to about -46 ° C or less. Therefore, the vessel 100 is provided with an evaporative gas processing device (not shown) for maintaining the LPG in the low temperature liquefied state. A reliquefaction system is employed as the evaporation gas processing system.

  The reliquefaction device cools the evaporated gas discharged by vaporization of LPG in the cargo tank 30 by the external heat outside the cargo tank 30 and liquefies it again. The gas liquefied in this way is returned to the cargo tank 30 as LPG. This maintains the low temperature state (for example, a temperature of −46 ° C. or less) in the LPG.

  The main engine 40 is disposed in the engine room 14 in the hull 10. The main unit 40 of the present embodiment is driven by using LPG as fuel. Here, the fuel of the main unit 40 is not limited to LPG, and may be combined (bifuel) of LPG and another fuel, mixed (dual fuel), or the like. By driving the main aircraft 40, the screw 41 provided below the stern of the hull 10 is rotated.

  Next, the fuel tank 50 will be described with reference to FIG. The fuel tank 50 of the present embodiment stores the LPG that is the fuel of the main engine 40. The fuel tank 50 is provided on the upper deck 13. In the present embodiment, for example, of the cargo tanks 30 arranged in three in the forward direction, they are provided on the upper deck 13 above the central cargo tank 30.

  The fuel tank 50 is capable of storing the LPG in a high pressure / normal temperature state. Therefore, the fuel tank 50 is configured of a pressure resistant container. In addition, "a high pressure normal temperature state" means the state by which the liquefied state of LPG is maintained only by pressurizing without cooling LPG.

  The fuel tank 50 has a cylinder 51 and a pair of lids 52. The cylindrical portion 51 has a cylindrical shape centered on the axis O. In the present embodiment, as shown in FIG. 3, the cross-sectional shape orthogonal to the axis O of the cylindrical portion 51 is circular, that is, the cylindrical portion 51 is cylindrical. The thickness of the wall constituting the cylindrical portion 51 is constant. The dimension in the direction of the axis O of the cylindrical portion 51 is larger than the diameter of the cylindrical portion 51. That is, the fuel tank 50 has the axis O direction as the longitudinal direction.

  The pair of lid portions 52 is provided to close both ends of the cylindrical portion 51 in the axis O direction. For example, the cylindrical portion 51 has a curved surface shape protruding outward from both ends of the cylindrical portion 51, and preferably has a spherical shape. As described above, the fuel tank 50 is constituted by the cylindrical portion 51 having a cylindrical shape and the pair of lid portions 52 having a curved surface shape, so that the pressure resistance is secured by forming the fuel tank 50 as a whole in a cylindrical shape. The outer peripheral surface centering on the axis line of the fuel tank 50 also has a cylindrical surface shape. The volume of the fuel tank 50 is sufficiently smaller than the volume of the cargo tank 30.

  Such a fuel tank 50 is provided on the upper deck 13 so as to be inclined downward as the axis O is directed to the bow side. That is, the fuel tank 50 extends along the axis O which goes downward as it goes to the bow side. The axis O coincides with the direction in which the ship 100 is seen in a plan view. The fuel tank 50 may be disposed in a pair so that the axes O of the fuel tanks 50 are parallel to each other in plan view while being spaced apart in the ship width direction.

  An axis O disposed above the upper deck 13 is inclined relative to the upper deck 13 so as to approach the upper deck 13 as it goes to the bow side. The inclination angle of the axis O with respect to the upper deck 13 is directed downward as the axis O is directed to the bow side with respect to the horizontal plane, even when the aft side of the ship 100 and the upper deck 13 is lowered when the ship 100 travels. To the extent that it can maintain its inclination.

  As shown in FIG. 2, a line connecting upper ends of the outer peripheral surface of the cylindrical portion 51 of the fuel tank 50 at the respective boat forward direction positions is referred to as an upper tank line La. The upper tank line La forms an upper contour in a side view of the ship 100. A line connecting the lower ends of the outer peripheral surface of the cylindrical portion 51 of the fuel tank 50 at each ship-to-ship direction position is a lower tank line Lb. The lower tank line Lb forms a lower contour in a side view of the ship 100.

  The upper tank line La and the lower tank line Lb are inclined downward toward the bow side. In the present embodiment, the upper tank line La and the lower tank line Lb are parallel to the axis O. Since the thickness of the cylindrical portion 51 constituting the fuel tank 50 is constant, the bottom surface defining the space in the fuel tank 50 is also inclined in the same manner as the lower tank line Lb because the lower tank line Lb is inclined. doing.

  The inclined attitude of the fuel tank 50 as described above is, for example, made by the tank support portion 60 that supports the inclined tank. The tank support 60 supports the fuel tank 50 on the upper deck 13 such that the axis O of the fuel tank 50 is inclined as described above. For example, in the present embodiment, the fuel tank 50 is supported by the upper ends of the bow side support 61 and the stern side support 62. The bow side support portion 61 and the stern side support portion 62 are each fixed on the upper deck 13, and the upper end of the stern side support portion 62 is positioned above the upper end of the bow side support portion 61. Due to the difference in height between the stern side support portion 62 and the bow side support portion 61, the inclined attitude of the fuel tank 50 is maintained. The configuration of the tank support portion 60 is not limited to the above configuration, and may be another configuration as long as the fuel tank 50 can be supported on the upper deck 13 in an inclined posture.

  Here, referring to FIG. 4, the inclination attitude of the fuel tank 50 will be described in more detail. The fuel tank 50 is disposed on the upper deck 13 so as to be below the visibility request line Lv shown in FIG. 4. Here, the visibility request line Lv is a virtual line connecting the cockpit 21 of the bridge 20 and a shorter position of twice the full length Loa of the ship 100 or 500 m from the bow on the water surface in front of the bow.

  That is, in the ship 100, according to the rule, a structure such as the fuel tank 50 on the upper deck 13 is a view from the cockpit 21 of the bridge 20 to the shorter position of twice the total length or 500m from the bow of the water surface in front of the bow. It is defined as a requirement not to interfere with More specifically, the base end of the view request line Lv on the bridge 20 side is defined as a position 750 mm from the front wall in front of the cockpit 21 to the aft side and a position 1800 mm from the floor surface. If the fuel tank 50 is disposed below the visibility request line Lv, that is, if the upper tank line La of the fuel tank 50 is not located above the visibility request line Lv, the requirement according to the above rule is satisfied. .

  In order to increase the volume of the fuel tank 50 as much as possible, the upper tank line La of the fuel tank 50 is preferably arranged as close as possible to the visibility request line Lv. The upper tank line La of the fuel tank 50 may be parallel to the visibility request line Lv. The upper tank line La of the fuel tank 50 may extend in line with the visibility request line Lv. That is, the upper tank line La of the fuel tank 50 may extend along the visibility request line Lv.

  Next, the pump 70 will be described. The pump 70 has a role of pumping LPG in the fuel tank 50 to the main machine 40, as shown in FIG. A drive unit such as an electric motor for driving the pump 70 may be provided in the fuel tank 50 or may be provided outside the fuel tank 50. In particular, since the LPG stored in the fuel tank 50 has an insulating property, there is no problem in providing a drive unit in the fuel tank 50.

  The pump 70 is provided with a suction port at the bow side of the fuel tank 50. In particular, in the present embodiment, the suction port of the pump 70 is disposed in the vicinity of the boundary between the cylinder 51 and the lid 52 on the bow side in the space inside the fuel tank 50. It is preferable that the suction port of the pump 70 be provided at the lowermost position in the space in the fuel tank 50 or in the vicinity of the position. The suction port of the pump 70 is preferably provided corresponding to the lowermost tank line Lb of the fuel tank 50. The fuel drawn from the pump 70 is transferred to the main unit 40 via the pipe 71.

Next, the operation of the present embodiment will be described.
In the present embodiment, the outer peripheral surface of the fuel tank 50 installed on the upper deck 13 extends along the axis O inclined downward toward the bow side. Therefore, it is possible to increase the volume of the fuel tank 50 within a range where the view can be maintained while securing a large view from the cockpit 21 of the bridge 20 to the front of the bow.

  That is, if the fuel tank 50 is inclined toward the bow side, it is possible to suppress obstructing the view from looking down toward the water surface from the cockpit 21 of the bridge 20 toward the bow side. Furthermore, since the stern side of the fuel tank 50 is positioned upward due to the inclined posture, the fuel tank 50 occupies a space that has not been used so far and does not hinder the visibility. Therefore, the fuel tank 50 can expand the effective volume which can store fuel.

  Furthermore, even if the fuel in the fuel tank 50 is relatively low because the pump 70 sucks the fuel from the portion on the bow side in the fuel tank 50 which is the lower part of the inclination of the fuel tank 50, The head of the pump 70 at the time of suction can be secured. That is, as shown in FIG. 2, when the remaining amount of LPG in the fuel tank 50 decreases, the LPG gathers on the bow side in the fuel tank 50 according to the inclination of the fuel tank 50. The pump 70 sucks the LPG thus collected through the suction port, so that the fuel in the fuel tank 50 can be prevented from remaining without being used to the end. That is, the ability of the pump 70 to extract fuel can be ensured.

  Here, if the inclination attitude of the fuel tank 50 is reverse to that of the present embodiment, that is, if the axis O of the fuel tank 50 is inclined downward toward the stern side, the bow side of the fuel tank 50 is upward Will be located in In this case, the view from the cockpit 21 of the bridge 20 may be obstructed. Also, in order to ensure visibility, the fuel tank 50 has to be installed at the stern side further, which hinders the freedom of installation. In addition, if the fuel tank 50 is installed on the bow side so as not to obstruct the view from the bridge 20, the fuel tank 50 itself needs to be configured small, and the effective volume is reduced.

  On the other hand, if the fuel tank 50 is disposed so as to extend downward as the axis O of the fuel tank 50 is directed to the bow side as in the present embodiment, the fuel tank 50 on the upper deck 13 is Of the fuel tank 50 on the deck can be improved. Furthermore, the volume of the fuel tank 50 can be maximized as long as the view from the bridge 20 is not impeded.

  Furthermore, in the present embodiment, in particular, the upper tank line La of the fuel tank 50 and the lower tank line Lb are parallel to the inclined axis O. That is, since the upper tank line La inclines downward toward the bow side, it is possible to further avoid the hindrance to the forward view of the bow from the bridge 20. Furthermore, since the lower tank line Lb inclines downward toward the bow side, the bottom surface constituting the space inside the fuel tank 50 also inclines in the same manner. Therefore, when the LPG in the fuel tank 50 decreases, the fuel in the fuel tank 50 is guided by the bottom to the bow side, so that the LPG can be collected in the bow side of the fuel tank 50. it can. Therefore, the pump 70 provided on the bow side in the fuel tank 50 can efficiently suck out the fuel collected on the front side.

  Furthermore, since the upper tank line La extends along the visibility request line Lv connecting the bridge 20 and the water surface in front of the bow when viewed from the boat width direction, the fuel tank 50 can meet the required rules. The volume of the fuel tank 50 can be maximized without impairing the visibility from the bridge 20 to the front of the bow.

  Further, since the fuel tank 50 has a cylindrical shape, the cost of manufacturing the fuel tank 50 can be reduced. Furthermore, a pressure-resistant structure for storing fuel in a high pressure state can be manufactured at low cost.

  Then, even if the cargo tank 30 storing LPG as cargo and the fuel tank 50 storing LPG as fuel are separately provided as in the present embodiment, as described above, the volume of the fuel tank 50 is increased. It is possible to secure visibility from the bridge 20 and suction of fuel in the fuel tank 50 while ensuring the maximum.

  As mentioned above, although embodiment of this invention was described, this invention can be suitably changed in the range which does not deviate from this within the technical idea of the invention, without being limited to this.

  For example, as a first modification, a fuel tank 150 shown in FIG. 5A may be adopted. The first modified fuel tank 150 has a shape in which two cylindrical portions 151 extending in the direction of the axis O are arranged in parallel with each other and united in part in the circumferential direction.

  As a second modification, a fuel tank 160 shown in FIG. 5 (b) may be employed. The fuel tank 160 of the second modification has an upper plate portion 161 and a lower plate portion 162 which extend along the axis O and face each other in the vertical direction. Both sides of the upper plate portion 161 and the lower plate portion 162 in the boat width direction are connected in an arc shape by a curved portion 163.

Furthermore, as a third modification, a fuel tank 170 shown in FIG. 5C may be adopted. The fuel tank 170 of the third modified example is configured of a rectangular tube portion 171 having a rectangular cross section extending along the axis O.
In any of the first to third modifications, the fuel tanks 150, 160, and 170 have an outer peripheral surface extending along an axis O inclined downward and an outer peripheral surface extending toward the bow side. An upper tank line La and a lower tank line Lb are included. Therefore, the same effect as that of the embodiment can be obtained.

  In the embodiment, the fuel stored in the fuel tank 50 is LPG, but another liquefied gas such as LNG may be used as the fuel. Further, the cargo stored in the cargo tank 30 is not limited to the LPG, and may be another liquefied gas. Furthermore, the cargo stored in the cargo tank 30 may be a liquid or material other than the liquefied gas.

DESCRIPTION OF SYMBOLS 10 Hull side 11 Hull side 12 Hull bottom 13 Upper deck 14 Engine room 15 Cargo hold 20 Bridge 21 Cockpit 30 Cargo tank 40 Main engine 41 Screw 50 Fuel tank 51 Tubular part 52 Lid part 60 Tank support part 61 Bow side support part 62 Stern side support part 70 pump 71 piping 100 ship 150 fuel tank 151 cylindrical portion 160 fuel tank 161 upper plate portion 162 lower plate portion 163 curved portion 170 fuel tank 171 square tube portion O axis line Lv view request line La upper tank line Lb lower tank line

Claims (5)

The hull,
A bridge disposed at the top of the stern side of the hull;
A main engine provided in the ship;
A fuel tank provided on the bow side of the bridge on the upper deck of the hull and having an outer circumferential surface extending along an axis along which the fuel of the main engine is stored and which inclines downward toward the bow side; ,
A pump having a suction port disposed at a bow-side portion in the fuel tank to suck out the fuel;
Ships equipped with   The ship according to claim 1, wherein an upper tank line and a lower tank line forming the outer peripheral surface of the fuel tank when viewed in the ship width direction are parallel to the axis.   The ship according to claim 2, wherein the upper tank line extends along a visibility request line connecting the bridge and a water surface in front of the bow, as viewed in the boat width direction.   The ship according to claim 2 or 3, wherein the outer peripheral surface of the fuel tank has a cylindrical surface shape centered on the axis. A cargo hold is formed in the hull,
The ship according to any one of claims 1 to 4, further comprising a cargo tank that is disposed in the cargo hold and stores liquefied gas.

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