JP2020199913A - Ship - Google Patents

Abstract

To provide an access trunk capable of suppressing mutual influence of force between a fuel tank and an exposed deck and capable of directly accessing to a TCS (a tank connection space) from the exposed deck.SOLUTION: A ship 10 is equipped with a fuel tank 20A to store a liquefied gas under the exposed deck 10D. An access trunk 50A makes it possible to access to a TCS20A and to the exposed deck 10D. A connection part 90 composed of a bellows-shaped hood is provided between the access trunk 50A and a TCS30A (a TCS passage part 36).SELECTED DRAWING: Figure 3

Description

The present invention relates to a ship that can use LNG or the like as fuel, and more particularly to an access to a connection portion of a fuel tank.

Vessels that can navigate using liquefied gas as fuel, such as LNG, are provided with a fuel tank that can store liquefied gas. For example, a cylindrical (IMO type-C) fuel tank independent of the hull is arranged in a compartment formed under the exposed deck (upper deck) (see, for example, Patent Document 1). A tank connection space (hereinafter referred to as TCS) is formed above the fuel tank so as to surround the connection between the piping on the fuel tank side and the external piping extending to the engine room or the like.

In the TCS, instruments such as a tank valve, a pressure gauge, and a thermometer, a gas detector, a fire detector, and the like are provided. It is also equipped with a ventilation trunk that extends onto the exposed deck while being formed as a gastight area with respect to the adjacent compartment to hold the leaked gas from the fuel tank. As a method for an operator to access the TCS for the purpose of inspection or the like, for example, an entrance / exit that allows direct access to the TCS from the exposed deck is provided (see Non-Patent Document 1).

JP-A-2018-134940

Journal of Marine Engineering Society of Japan, by Koichi Nishifuji, Vol. 47, No. 6, published in 2012

When the liquefied gas is stored in the fuel tank, the fuel tank heat-shrinks because the liquefied gas has a low temperature. On the other hand, the hull bends due to the influence of waves and the like. In the configuration provided with an entrance / exit that allows direct access to the TCS from the exposed deck, when the fuel tank heat contracts, a force is applied to the exposed deck that is connected to the TCS and supported by the hull, which affects the strength of the hull. Further, when the hull is bent, it affects the strength of the TCS installed on the fuel tank.

Therefore, it is required to provide a vessel that suppresses mutual influence of force between the TCS and the exposed deck and enables direct access to the TCS from the exposed deck.

The ship of the present invention is, for example, a ship equipped with a fuel tank capable of storing liquefied gas, and has a fuel tank arranged under the exposed deck and a connection portion of the fuel tank, that is, a pipe on the fuel tank side and an external pipe. It is provided with a TCS that surrounds the connection portion of. The ship of the present invention forms at least a part of a dedicated passage facility (called an access trunk) provided for accessing the TCS from the exposed deck and a passage (called an access passage) through which a person passes from the exposed deck to the TCS. It also has an elastic part that elastically deforms. For example, the access trunk is provided so as to form a part of the access passage, and the elastic portion can be configured separately from the access trunk. Alternatively, the access trunk can be provided to form the entire access passage, and the elastic portion can be configured as part of the access trunk. The fuel tank can be configured as a cylindrical fuel tank independent of the hull, for example, the TCS is provided above the fuel tank.

The elastic part of the present invention can form a part or the whole of the access passage from the exposed deck to the TCS. When forming a part of the access passage, the elastic part can be provided along the access passage closer to the TCS than the exposed deck. Further, the elastic portion can also form at least a part of the passage portion that forms the passage space in the horizontal direction in the access passage. However, it is not limited to forming the passage space strictly in the horizontal direction, as long as the operator can move in the lateral direction.

The elastic portion can be configured as a connecting portion connecting the TCS side end portion of the access trunk and the TCS, and can be configured as a bellows-shaped hood.

Further, the ship of the present invention spatially separates a gas-tight area provided on the exposed deck, a ventilation trunk provided with a duct extending from the TCS to the exposed deck side, and the gas-tight area and the duct. It is also possible to further provide a connecting pipe to connect to.

According to the present invention, it is possible to provide an access trunk that suppresses mutual influence of force between the TCS and the exposed deck and enables direct access to the TCS from the exposed deck.

It is the schematic which looked at the internal structure near the fuel tank of the ship which is this embodiment from the stern side. It is a block diagram which looked at the access trunk and TCS from above. It is a block diagram which saw the access trunk and TCS from the ship side. It is a side view which looked at the connecting part from the side.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic view of the internal configuration of the vicinity of the fuel tank of the ship according to the present embodiment as viewed from the stern side.

Vessel 10 is a vessel capable of navigating using liquefied gas such as LNG as fuel, and is equipped with a pair of fuel tanks 20A and 20B. The fuel tanks 20A and 20B are tanks capable of storing liquefied gas such as LNG, and here, they are independent fuel tanks of type-C defined by the IGC code of IMO and the IGF code, that is, independent of the hull 10B. It consists of a horizontal cylindrical pressure vessel.

The fuel tanks 20A and 20B are arranged in a gastight area below the exposed deck (upper deck) 10D and are supported by support members (not shown). Here, the fuel tanks 20A and 20B are arranged side by side with respect to the hold 10H formed under the exposed deck 10D with the spherical portion facing the bow-stern direction and the central line C in the hull width direction. The fuel tanks 20A and 20B employ a heat-insulating structure, and maintain the temperature of the tank surface at the outside air temperature when a low-temperature liquefied gas such as LNG is injected.

The tank dome 21A provided on the upper part of the fuel tank 20A is provided with a connection portion 22A for connecting the piping from the inside of the tank and the external piping, an on-off valve (not shown), and the like, and the TCS (tank connection space) 30A is provided. It is installed above the tank dome 21A so as to surround the connection portion 22A. The TCS30A is composed of a rigid square structure and is installed on the fuel tank 20A. For the fuel tank 20B, a TCS30B similar to the TCS30A is installed above the tank dome 21B so as to surround the connection portion 22B.

Inside the TCS30A and 30B, a pressure gauge, a thermometer, a gas detector, a fire detector, and the like are provided, and are formed as a gas-tight area so as to hold the leaked liquefied gas. Further, ventilation trunks 40A and 40B for exhausting the gas in TCS30A and 30B to the exposed deck 10D side are equipped, and an exhaust fan and the like are installed.

In the present embodiment, access trunks 50A and 50B are provided to enable direct access from the exposed deck 10D to the inside of the TCS 30A and 30B. The operator enters the inside of the TCS 30A and 30B through the access trunks 50A and 50B, and inspects the on-off valve and the instrument. The access trunks 50A and 50B will be described in detail below.

FIG. 2 is a block diagram of the access trunk 50A and the TCS 30A as viewed from above (exposed deck side). FIG. 3 is a configuration diagram of the access trunk 50A and the TCS 30A as viewed from the ship side. Since the access trunk 50B has the same structure as the access trunk 50A, only the access trunk 50A will be described below.

The access trunk 50A is exposed to a passage portion (hereinafter referred to as a lateral passage portion) 70 that forms an L-shaped passage when viewed from above and forms a passage space in a direction (horizontal direction) along the exposure deck 10D. It is composed of an inclined passage portion 80 forming a passage space extending diagonally upward toward the deck 10D. The lateral passage portion 70 and the inclined passage portion 80 have an integral structure composed of a rectangular frame having continuous rigidity, and are supported by the hull 10B. A staircase 95 is installed in the inclined passage portion 80 (not shown in FIG. 2), and an opening 85 is formed in the exposed deck 10D on the exposed deck end side of the inclined passage portion 80.

As shown in FIG. 2, the end portion of the lateral passage portion 70, that is, the TCS side end portion of the access trunk 50A is connected to the TCS 30A via the connecting portion 90. An opening 34 is formed in the TCS 30A, and a TCS passage portion 36 formed of a continuous frame protruding from the opening 34 to the outside of the TCS 30A is formed. The connecting portion 90 spatially connects the TCS 30A and the access trunk 50A by connecting one end thereof to the TCS passage portion 36 and the other end connecting the lateral passage portion 70.

FIG. 4 is a side view of the connecting portion 90 as viewed from the side. Here, the connecting portion 90 is composed of a bellows-shaped hood, and a structure similar to that of a through hood of a railway vehicle can be adopted. The connecting portion 90 is formed by a flexible member that is elastically deformable in the passage direction and any other direction, and is made of, for example, rubber.

As shown in FIG. 3, a rectangular small room 110 covering the opening 85 of the access trunk 50A is installed on the exposed deck 10D to form a gas-tight area. When the worker enters the small room 110 through the opening / closing door 120, he / she enters the access trunk 50A through the opening 85 and passes through the access trunk 50A. In the small room 110, the duct (connecting pipe) 130 extends horizontally from the side surface of the room and is spatially connected to the duct 42A of the ventilation trunk 40A. Therefore, the ventilation trunk 40A is composed of the duct 42A and the duct 130.

As described above, the TCS 30A is installed on the fuel tank 20A. Since the liquefied gas such as LNG has a low temperature, the fuel tank 20A is thermally shrunk by the fuel injection, and the tank surface is displaced. The TCS30A installed on the fuel tank 20A is also displaced accordingly. At this time, the access trunk 50A is prevented from being displaced by extending the connecting portion 90 connected to the TCS 30A (TCS passage portion 36). As a result, the access trunk 50A is not affected by the force from the TCS30A side. Even when the fuel tank 20A thermally expands, the displacement of the access trunk 50A can be suppressed by shrinking the connecting portion 90.

On the other hand, when the hull 10B bends due to waves or the like, the access trunk 50A supported by the hull 10B is displaced according to the bending of the exposed deck 10D. At this time, the displacement of the TCS 30A is suppressed by expanding or contracting the connecting portion 90. As a result, the fuel tank 20A is not affected by the force from the access trunk 50A side.

In this way, a part of the passage (access passage) PT (arrow portion in FIG. 2) through which the operator passes from the opening 85 of the access trunk 50A to the opening 34 of the TCS 30A is configured by the elastically deformable flexible connecting portion 90. Therefore, the displacement of the TCS 30A or the access trunk 50A can be suppressed while adjusting the total length of the passage.

In particular, by installing the connecting portion 90 in the vicinity of the TCS 30A, the connecting portion 90 can be flexibly deformed with respect to thermal expansion and contraction of the fuel tank 20A. Further, by connecting the connecting portion 90 to the lateral passage portion 70 along the exposed deck 10D, the structure of the access trunk 50A can be adopted as it is, and further, a deformable bellows-shaped hood can be adopted. Will be easier to adopt.

The connecting portion 90 can also be formed of an elastic member other than the bellows-shaped hood, and is installed near the opening 85 of the access trunk 50A, that is, the access trunk 50A is attached to the exposed deck 10D via the connecting portion 90. It may be configured to be connected. Further, as a part of the access trunk 50A, the connecting portion 90 may be arranged on the passage of the lateral passage portion 70 or the inclined passage portion 80. It is also possible to equip the access trunk 50A that connects the TCS 30A and the exposed deck 10D without providing the connecting portion 90, and to configure a part or the whole thereof as an elastic body.

On the other hand, in the present embodiment, the TCS 30A to the small room 110 on the exposed deck 10D are spatially connected and can be regarded as one TCS. Therefore, it is not necessary to newly provide a duct for the access trunk 50A, and one ventilation trunk 40A can be configured by the duct 42A and the duct 130.

In view of such a configuration, it is possible to provide a ship that does not have an elastic body such as the connecting portion 90. That is, a fuel tank arranged under the exposed deck, a TCS surrounding the connection portion of the fuel tank, an access trunk connecting the exposed deck and the TCS, and a gas-tight area surrounding the opening of the access trunk provided on the exposed deck. , A vessel can be provided that includes a ventilation trunk with a duct extending from the TCS to the exposed deck side and a connecting pipe that spatially connects the gastight area with the duct.

Simply installing an access trunk requires an independent ventilation trunk for the access trunk. However, by providing a gas-tight area (small room) surrounding the opening of the access trunk on the exposed deck and connecting the gas-tight area and the ventilation trunk with a connecting pipe, one TCS including the access trunk can be formed. You only need to equip one ventilation trunk.

In this embodiment, a type-C stand-alone fuel tank is provided, but it may be applied to other fuel tanks. Further, it may be composed of a ship equipped with three or more or one fuel tank.

10 Ship 10B Hull 10D Exposed deck 20A, 20B Fuel tank 22A, 22B Connection 30A, 30B TCS (tank connection space)
40A, 40B Ventilation trunk 50A, 50B Access trunk 90 Connecting part (elastic part)
PT access passage

Claims (8)

A fuel tank located under the exposed deck and
A tank connection space (hereinafter referred to as TCS) surrounding the connection portion of the fuel tank and
An access trunk provided to access the TCS from the exposed deck,
A ship comprising an elastic portion that forms at least a part of an access passage from the exposed deck to the TCS and is elastically deformed. The ship according to claim 1, wherein the elastic portion is provided near the TCS from the exposed deck along the access passage. The ship according to claim 1 or 2, wherein the elastic portion forms at least a part of a passage portion of the access passage that forms a passage space in the horizontal direction. The ship according to any one of claims 1 to 3, wherein the elastic portion is configured as a connecting portion that connects the TCS side end portion of the access trunk and the TCS. The ship according to any one of claims 1 to 4, wherein the elastic portion is configured as a bellows-shaped hood. A gastight area covering the opening of the access trunk provided on the exposed deck, and
A ventilation trunk with a duct extending from the TCS to the exposed deck side,
The ship according to any one of claims 1 to 5, further comprising a connecting pipe for spatially connecting the gas-tight area and the duct. The fuel tank is a cylindrical fuel tank independent of the hull.
The ship according to any one of claims 1 to 6, wherein the TCS is provided on the upper part of the fuel tank. The ship according to any one of claims 1 to 7, wherein the liquefied gas can be stored in the fuel tank.

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