JP6609828B2 - Deck placing tank structure, ship, tank installation method and inspection method - Google Patents

Description

  The present invention relates to a deck placing tank structure, a ship, a tank installation method, and an inspection method.

In ships, it is desired to suppress emission of air pollutants such as carbon dioxide and sulfur oxides. In order to suppress the discharge of such air pollutants, there is a method using liquefied gas (LNG, LPG, etc.) as fuel.
Patent Document 1 and Patent Document 2 describe a ship in which a liquefied natural gas fuel tank is installed on an upper deck. Moreover, the tank structure described in Patent Document 1 supports the fuel tank from below by using a lattice-like frame body that is arranged so as to be spaced upward from the upper deck by a plurality of saddles.

JP 2014-162430 A Special table 2013-530865 gazette

In the tank structure of Patent Document 1, after a tank is installed on a grid-like frame, tank covers are attached to the upper, front, rear, lower, and both sides of the tank. At this time, since the lower tank cover is installed between the tank and the grid-like frame body, there is a problem that workability when the lower tank cover is attached is poor.
Moreover, when inspecting the inside of a tank cover after attaching a tank cover, the operation | work which removes a lower tank cover is needed, for example. At that time, similarly to the attachment of the tank cover, there is a problem that workability is poor due to the installation of the grid-like frame.

  The present invention has been made in view of the above circumstances, and provides a deck storage tank structure, a ship, a tank installation method and an inspection method capable of improving workability such as installation and inspection.

In order to solve the above problems, the following configuration is adopted.
According to the first aspect of the present invention, the deck laying tank structure includes a plurality of saddles provided at intervals so as to protrude from the deck of the ship, and supported by the plurality of saddles from below, in plan view. A lattice material having a lattice shape, a plurality of support portions disposed on the upper surface of the lattice material, a tank supported by the plurality of support portions from below and containing liquefied gas therein, and supported by the lattice material And an upper cover that covers the side and upper side of the tank, and a plurality of lower covers that form a sealed space together with the upper cover by being attached so as to close the lattice-shaped openings of the lattice material.
By configuring in this way, for example, when constructing a tank structure, the lattice-shaped openings of the lattice material can be finally closed by the lower cover. Further, when inspecting the tank structure, only the lower cover near the portion to be inspected can be removed, and the inside of the cover can be inspected through the lattice-shaped openings.
Therefore, since the lower cover can be easily attached / detached, workability when attaching / detaching the cover can be improved.

According to the second aspect of the present invention, in the deck placing tank structure according to the first aspect, the deck cover tank structure is formed by the lower cover attached so as to close the opening of the lattice material and the lattice material surrounding the opening. In addition, a recess that opens upward may be provided.
By comprising in this way, the recessed part formed with a grating | lattice material and a lower cover can be utilized as a container which receives the liquefied gas which leaked from the tank. As a result, an increase in the number of parts can be suppressed as compared with a case where a container for receiving liquefied gas is separately provided.

According to a third aspect of the present invention, in the deck laying tank structure according to the first aspect, a heat insulating material that covers the surface of the tank is provided, and at least one of the surface of the tank and the heat insulating material leaks from the tank. A groove for guiding the liquefied gas to the recess may be provided.
By comprising in this way, even if it is a case where the heat insulating material and the surface of a tank are closely_contact | adhering, the leaked liquefied gas can be guided to a recessed part by a groove part.

According to the fourth aspect of the present invention, the support portion according to the first to third aspects adjusts the height of the heat insulating block having a lower thermal conductivity than the tank and the lattice material and the height of the upper surface of the heat insulating block. A height adjusting member.
Thus, when the support part is provided with the heat insulating block and the height adjusting member, the height adjustment of the upper surface of the heat insulating block by the height adjusting member can be performed through the lattice-shaped openings. Therefore, it is possible to easily adjust the clearance between the support portion and the tank.

According to a fifth aspect of the present invention, the tank according to any one of the first to fourth aspects has any one of a rectangular tank, a cylindrical tank, and a spherical tank, LNG or LPG may be accommodated as the liquefied gas.
By configuring in this way, after placing the tank on the support portion and installing the upper cover, it is only necessary to attach and detach the lower cover with respect to the lattice-shaped openings. Therefore, a rectangular tank for LNG and LPG, a cylindrical tank, In addition, the spherical tank can be easily installed and can be easily inspected.

According to the sixth aspect of the present invention, the ship includes the deck placing tank structure according to the first to fifth aspects.
By comprising in this way, the tank which accommodates liquefied gas can be easily installed on the upper deck located above cargo spaces etc., for example. As a result, it is possible to suppress a decrease in cargo space and living space.

According to the seventh aspect of the present invention, a tank installation method includes a support part installation step of installing a plurality of support parts on an upper surface of a lattice material having a lattice shape in plan view, and a tank in which liquefied gas is accommodated. Through the tank installation step of installing the support member on the support portion so as to be supported from below by the plurality of support portions, and adjusting the clearance between the support portion and the tank through the lattice-shaped openings of the lattice member. An adjustment step, a closing step of sealing a lattice-shaped opening of the lattice material with a lower cover, a hull side saddle attachment step of attaching a plurality of saddles supporting the lattice material from below, and a plurality of the saddles And a grid material side saddle mounting process to be mounted on the grid material.
Thus, after adjusting the clearance between the support portion and the tank through the lattice-shaped opening of the lattice material, the lower cover can be attached to the lattice-shaped opening of the lattice material and sealed. Therefore, the burden on the worker who installs the tank can be reduced.

According to an eighth aspect of the present invention, in the tank installation method according to the seventh aspect, the lattice material side saddle attachment step may be performed after the hull side saddle attachment step in the tank installation method according to the seventh aspect. .
By doing in this way, for example, after performing a hull side saddle attachment process, a lattice material side saddle attachment process, a support part installation process, a tank installation process, an adjustment process, and a closure process can be performed on board.

According to a ninth aspect of the present invention, in the tank installation method according to the seventh aspect, the hull side saddle attachment step may be performed after the lattice material side saddle attachment step in the tank installation method according to the seventh aspect. .
By doing in this way, the saddle attached to the lattice material can be attached to the hull. Therefore, for example, since the grid material side saddle mounting process can be performed outside the ship, when the tank is installed in a ship or the like in service, the period for putting the ship in the dock can be shortened.

According to a tenth aspect of the present invention, there is provided a tank installation method according to the eighth aspect, wherein the hull side saddle attachment step is performed at least after the support portion installation step and the tank installation step. May be.
By doing in this way, for example, after performing the support part installation process, the tank installation process, etc. in the factory, etc., and after performing the lattice material side saddle installation process, the assembled assembly is lifted with a crane or the like, The saddle can be secured to the hull after being moved onto the ship's deck. Therefore, when installing in the ship etc. which are in service, the period which puts a ship in a dock can further be shortened.

According to the eleventh aspect of the present invention, an inspection method includes a plurality of saddles provided at intervals so as to protrude from a deck of a ship, and supported from below by the plurality of saddles, and in a plan view. A lattice material having a shape, a plurality of support portions disposed on the top surface of the lattice material, a tank supported by the plurality of support portions from below and containing liquefied gas therein, and supported by the lattice material A deck cover comprising: an upper cover that covers a side and an upper side of the tank; and a plurality of lower covers that are attached so as to close a lattice-shaped opening of the lattice material to form a sealed space together with the upper cover. A tank structure inspection method for removing a part of the lower cover from the lattice material among the plurality of lower covers attached to close the lattice-shaped opening of the lattice material A bar removing step, an inspection step of checking the inside of the sealed space through the opening from which the lower cover has been removed, a re-blocking step of resealing the opening by the lower cover removed in the lower cover removing step, including.
By doing in this way, only the lower cover of a required location can be attached or detached from the downward direction of a lattice material, and the inside of sealed space can be inspected. Therefore, the burden on the worker who performs the inspection can be reduced.

  According to the deck storage tank structure, ship, tank installation method and inspection method, it is possible to improve workability such as installation and inspection.

It is a perspective view which shows schematic structure of the ship in embodiment of this invention. 1 is an enlarged perspective view of a tank structure 1A according to an embodiment of the present invention. It is a perspective view of a saddle, a lattice material, and a tank body. It is the perspective view which looked at the lattice material in the state supported by the saddle from above. It is the perspective view which looked at the tank structure in embodiment of this invention from the downward direction. It is a side view of a tank structure in an embodiment of this invention. It is a flowchart of the installation method of the tank structure in embodiment of this invention. It is explanatory drawing of the adjustment process in the installation method of the said tank structure. It is a flowchart of the inspection method in embodiment of this invention. It is a flowchart of the installation method of the tank structure in the 1st modification of embodiment of this invention. It is a flowchart of the installation method of the tank structure in the 2nd modification of embodiment of this invention. It is a perspective view of the tank main body in the 3rd modification of embodiment of this invention.

Next, a deck placing tank structure, a ship, a tank installation method and an inspection method according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a schematic configuration of a ship according to an embodiment of the present invention.
As shown in FIG. 1, the ship 2 of this embodiment includes a hull 8, an upper structure 9, and a tank structure (deck placing tank structure) 1 </ b> A.

  The ship 2 exemplified in this embodiment is a ship such as a tanker that transports oil, and an upper structure 9 and a tank structure 1A are disposed on an upper deck (deck) 10 that is an exposed deck of the hull 8. Each is arranged. The upper structure 9 has a residential area and a bridge, and is disposed closer to the stern in the bow-stern direction than the cargo space for storing the oil as cargo.

  The tank structure 1A is arranged so as to be adjacent to the bow side of the upper structure 9. Two tank structures 1A in this embodiment are arranged in the ship width direction. These tank structures 1 </ b> A have their upper surfaces disposed below the bridge in order to ensure visibility from the bridge of the upper structure 9.

FIG. 2 is an enlarged perspective view of the tank structure 1A according to the embodiment of the present invention. FIG. 3 is a perspective view of the saddle, the lattice material, and the tank body. FIG. 4 is a perspective view of the lattice material supported by the saddle as viewed from above.
As shown in FIGS. 2 to 4, the tank structure 1 </ b> A includes a saddle 3, a lattice material 4, a support portion 5 </ b> A, a tank body 6 </ b> A, and a tank cover 7.
The saddle 3 is provided so as to protrude upward from the upper deck 10. A plurality of saddles 3 are provided at intervals, and support the lattice material 4 from below. The saddle 3 illustrated in this embodiment has an X-shaped cross section, and a lower end portion of the saddle 3 is attached to the lower surface of the upper deck 10 and extends in the ship width direction or the bow-stern direction (for example, (Not shown) or the like. Moreover, the saddle 3 in this embodiment has a length from the upper deck 10 to the upper end thereof of about 2 m.

  As shown in FIG. 4, the lattice material 4 is formed in a lattice shape. The lattice material 4 is supported from below by the plurality of saddles 3 described above. More specifically, the lattice material 4 is arranged in a posture parallel to the upper deck 10, and the upper end portion of the saddle 3 is fixed to the lower surface thereof. The lattice material 4 in this embodiment is formed of, for example, H-shaped steel or I-shaped steel. The lattice material 4 includes an outer frame portion 15, a vertical beam portion 16, and a horizontal beam portion 17.

  The outer frame portion 15 forms a rectangular outer frame. The outer frame portion 15 in this embodiment includes a pair of vertical members 15a extending in the bow-stern direction and a pair of cross members 15b extending in the ship width direction. The vertical beam portions 16 are formed so as to extend in the bow-stern direction, and a plurality of the vertical beam portions 16 are provided inside the outer frame portion 15 at intervals in the ship width direction. The transverse beam portions 17 are formed so as to extend in the ship width direction, and a plurality of the transverse beam portions 17 are provided inside the outer frame portion 15 at intervals in the bow-stern direction. The vertical beam portion 16 and the horizontal beam portion 17 intersect each other inside the outer frame portion 15. In addition, in this embodiment, although the case where the five vertical beam parts 16 and the three horizontal beam parts 17 are provided is illustrated, the number of the vertical beam parts 16 and the horizontal beam parts 17 is not restricted to the said number.

  A plurality of support portions 5 </ b> A are arranged on the upper surface 4 u of the lattice material 4. 5 A of support parts illustrated in this embodiment are arrange | positioned in the location where the vertical beam part 16 and the horizontal beam part 17 cross | intersect, respectively. The upper surfaces 5a of the plurality of support portions 5A are disposed so as to contact the lower surface (see FIG. 8) of the tank body 6A. The support portion 5 </ b> A includes a heat insulating block 20. The heat insulation block 20 is formed of a material having a lower thermal conductivity than the tank body 6 </ b> A and the lattice material 4, such as a synthetic resin such as phenol resin, and wood. In this way, the support portion 5A suppresses heat conduction from the tank body 6A, which is at a very low temperature, to the lattice material 4 while supporting the tank body 6A from below.

  The tank body (tank) 6A accommodates, for example, liquefied natural gas (LNG), which is fuel for navigating the ship. As shown in FIG. 3, the tank body 6A in this embodiment is a rectangular tank provided with a trunk top 21 for handling liquefied natural gas or the like at the upper center. The tank body 6A is supported from below by the plurality of support portions 5A described above. The tank body 6A is made of a metal such as an aluminum alloy that does not brittlely break against the cryogenic temperature of liquefied natural gas. The tank body 6A in this embodiment is covered with a heat insulating material 40 (see FIG. 8) such as polyurethane, except for the portion that comes into contact with the support portion 5A described above.

FIG. 5 is a perspective view of the tank structure according to the embodiment of the present invention as viewed from below.
As shown in FIGS. 2 and 5, the tank cover 7 is disposed so as to cover the tank main body 6A described above, and forms a sealed space around the tank main body 6A. The tank cover 7 includes an upper cover 22 and a lower cover 23 (see FIG. 5).

  The upper cover 22 is supported by the lattice material 4 and covers the side and upper side of the tank body 6A. More specifically, the upper cover 22 includes an upper wall portion 22a and a side wall portion 22b. The upper wall portion 22a is formed in a rectangular plate shape that covers the tank body 6A. Each of the side wall portions 22b is formed in a cylindrical shape having a rectangular cross section extending downward from the four sides of the upper wall portion 22a. In the upper cover 22 formed in this way, the opening edge 22c facing downward is fixed to the outer frame portion 15 of the lattice material 4 described above by welding or the like.

  A plurality of lower covers 23 are provided, and are attached so as to block a plurality of lattice-shaped openings 4 a (see FIG. 4) formed by the lattice material 4. The plurality of lower covers 23 together with the upper cover 22 form a sealed space isolated from the outside around the tank body 6A. More specifically, a sealed space is formed by the lower cover 23, the upper cover 22, and the lattice material 4. The lower cover 23 exemplified in this embodiment is formed in a rectangular plate shape slightly larger than the opening 4a. For example, the entire circumference of the outer peripheral portion 23a of the lower cover 23 is fixed to the lower surface of the lattice material 4 at the periphery of the opening 4a by welding or the like. In other words, the openings 4a of the lattice material 4 are sealed from below by the lower covers 23, respectively.

  The lower cover 23 closes the opening 4a of the lattice material 4 from below, thereby forming a recess 50 (see FIG. 6) that opens upward together with the lattice material 4 on the periphery of the lower cover 23. In addition, in FIG. 5, the case where the lower cover 23 which plugs up one opening 4a and the lower cover 23 which plugs up two openings 4a is illustrated. However, the configuration of the lower cover 23 is not limited to the above configuration. For example, one opening 4 a may be closed with a plurality of lower covers 23, or three or more openings 4 a may be closed with one lower cover 23.

FIG. 6 is a side view of the tank structure according to the embodiment of the present invention.
As shown in FIG. 6, in the tank structure 1A in this embodiment, the surface of the tank main body 6A and the inner surface of the heat insulating material 40 covering the surface are in close contact, and the surface of the tank main body 6A and the inner surface of the heat insulating material 40 At least one of them has a groove 41. For example, when the liquefied natural gas gradually leaks from the tank body 6A, the groove portion 41 guides the leaked liquefied natural gas. More specifically, the liquefied natural gas leaked from the tank body 6A is guided to a predetermined recess 50A among the plurality of recesses 50 formed by the lattice material 4 and the lower cover 23 described above.

  Here, the groove portions 41 exemplified in this embodiment are formed in a lattice shape so as to extend in the vertical and horizontal directions, and are slightly inclined so that the liquefied natural gas can move by its own weight toward the predetermined concave portion 50A. Is formed. The predetermined recess 50A may be provided with a cover member formed of a material that is difficult to be brittlely destroyed at low temperatures. Further, a part of the lattice material 4 that forms the predetermined concave portion 50A and the lower cover 23 that forms the predetermined concave portion 50A may be formed of a material that is difficult to brittlely break at a low temperature. In addition, although the case where the groove part 41 was formed in a grid | lattice shape was illustrated, the groove part 41 should just be a shape which can guide liquefied natural gas to the predetermined recessed part 50A, and is not restricted to the said shape.

Next, a method for installing the tank structure 1A described above will be described with reference to the drawings.
FIG. 7 is a flowchart of the tank structure installation method according to the embodiment of the present invention. FIG. 8 is an explanatory diagram of an adjustment process in the tank structure installation method. In the description of the method for installing the tank structure 1A, a case where the installation work is mainly performed on the upper deck 10 will be described as an example.

  As shown in FIG. 7, first, a hull side saddle mounting step (step S01) is performed. In this hull side saddle mounting, a plurality of saddles 3 are installed at intervals so as to protrude from the upper deck 10 of the ship 2.

  Next, a lattice material side saddle mounting step (step S02) is performed. In the grid material side saddle mounting process, the grid material 4 having a lattice shape in plan view is mounted on the saddle 3 so as to be supported from below by the plurality of saddles 3 installed in the hull side saddle mounting process. At this time, for example, the saddle 3 is fixed so as not to be detached from the lattice material 4 by welding or the like around the entire circumference of the saddle 3. Thereby, the lattice material 4 is installed in the attitude | position arrange | positioned on the virtual surface parallel to the upper deck 10. As shown in FIG.

  Then, the support part installation process (step S03) which installs several support part 5A in the upper surface of the grating | lattice material 4 is performed. In this support portion installation step, the plurality of support portions 5A are arranged in a predetermined arrangement spaced apart from each other in the fore-and-aft direction and the ship width direction so that the load of the tank body 6A is dispersed.

  And a tank installation process (step S04) is performed. In this tank installation step, the tank body 6A is installed on the support portion 5A so as to be supported from below by the plurality of support portions 5A. At this time, the tank body 6A is installed so that the heat insulating block 20 of the support portion 5A contacts the lower surface 6a of the tank body 6A. In the tank installation process in this embodiment, after the tank body 6A is installed, the heat insulating material 40 is attached to the tank body 6A. Furthermore, the upper cover 22 is installed, and the opening edge 22c of the upper cover 22 and the outer frame portion 15 of the lattice material are fixed by welding or the like.

  Next, an adjustment process (step S05) is performed. In this adjustment step, for example, the clearance between the support portion 5A and the tank body 6A is adjusted through the lattice-like openings 4a of the lattice material 4. At this time, the operator performs adjustment work on a scaffold or the like assembled below the lattice material 4. As shown in FIG. 8, just by installing the tank body 6A, there may be a gap between the heat insulating block 20 of the support portion 5A and the lower surface 6a of the tank body 6A. Therefore, in this adjustment process, the height position of the heat insulation block 20 is adjusted so that all the heat insulation blocks 20 of the plurality of support portions 5A are in contact with the lower surface 6a of the tank body 6A. As an adjustment method in this adjustment process, the method shown in FIG. 8 can be illustrated. In the adjusting method shown in FIG. 8, a shim plate 53 having a thickness corresponding to the gap is inserted as a height adjusting member from the side where the rib material 52 is not disposed between the heat insulating block 20 and the lattice material 4. Thus, the height position of the heat insulating block 20 is adjusted so that the upper surface of the heat insulating block 20 (in other words, the upper surface 5a of the support portion 5A) is in contact with the lower surface 6a of the tank body 6A.

Thereafter, a closing process (step S06) is performed. In this closing step, the lattice-shaped openings 4 a of the lattice material 4 are closed by the lower cover 23. More specifically, the operator closes all of the plurality of openings 4 a from below with a plurality of lower covers 23 on a scaffold or the like assembled below the lattice material 4. At this time, the entire periphery of the lower cover 23 is fixed to the lattice material 4 by welding or the like so that the opening 4 a is sealed by the lower cover 23. Thereby, a sealed space is formed between the tank cover 7 and the tank body 6A.
And the scaffolding etc. which were assembled under the grid | lattice material 4 are disassembled, and the installation operation | work of the tank structure 1A is complete | finished.

Next, an inspection method for the tank structure 1A installed as described above will be described with reference to the drawings.
FIG. 9 is a flowchart of the inspection method in the embodiment of the present invention.
As shown in FIG. 9, first, a lower cover removing step (step S10) is performed. In the lower cover removing step, some of the lower covers 23 are removed from the lattice material 4 among the plurality of lower covers 23 attached so as to close the lattice-shaped openings 4 a of the lattice material 4. More specifically, the lower cover 23 that closes the opening 4a close to the inspection location is removed. At this time, a scaffold or the like is assembled below the lattice material 4 and the lower cover 23 is removed from below the lattice material 4.

  Next, an inspection process (step S11) is performed. In this inspection process, the inside of the sealed space is inspected, for example, visually through the opening 4a from which the lower cover 23 has been removed. At this time, an operator may enter the tank cover 7 through the opening 4a. In addition, if it is determined by inspection that repair or the like is necessary, the repair work may be performed as it is.

Thereafter, a re-occlusion step (step S12) is performed. In this re-closing process, the opening 4 a from which the lower cover 23 has been removed in the lower cover removing process is sealed again by the lower cover 23. At this time, the removed lower cover 23 may be reused. For example, when the lower cover 23 is damaged due to the removal, a new lower cover 23 may be used.
And the scaffolding etc. which were assembled under the grid | lattice material 4 are disassembled, and an inspection is complete | finished.

  Therefore, according to the above-described embodiment, for example, when the tank structure 1A is constructed, the clearance adjustment between the support portion 5A and the tank body 6A is performed through the lattice-shaped opening 4a, and finally the lattice material 4 is formed by the lower cover 23. The lattice-like openings 4a can be closed. Further, when inspecting the tank structure 1A, it is possible to inspect the inside of the tank cover 7 through the lattice-like opening 4a by removing only the lower cover 23 near the location to be inspected. As a result, workability such as installation and inspection of the tank structure 1A can be improved, and the burden on the operator can be reduced.

  Further, the recess 50 formed by the lattice material 4 and the lower cover 23 can be used as a container for receiving the liquefied natural gas leaked from the tank body 6A. As a result, an increase in the number of parts can be suppressed as compared with a case where a container for receiving liquefied natural gas is separately provided.

Moreover, when performing a clearance adjustment operation | work, it can carry out through the grid | lattice-like opening 4a from the downward direction. Further, the clearance between the heat insulating block 20 and the tank body 6A can be easily confirmed from the opening 4a by visual observation or the like.
And by employ | adopting the said tank structure 1A, the square tank for liquefied natural gas can be easily installed on the upper deck 10 grade | etc.,.

  In the tank structure installation method of the above-described embodiment, the case where the saddle installation process (step S01) and the lattice material installation process (step S02) are performed first has been described. However, the timing of attaching the saddle 3 to the lattice material 4 is not limited to the timing of the above-described embodiment.

(First modification of embodiment)
FIG. 10 is a flowchart of the tank structure installation method according to the first modification of the embodiment of the present invention. In the description of the first modified example, the same steps as those in the above-described embodiment are described with the same reference numerals, and redundant descriptions are omitted.
As shown in FIG. 10, in the tank structure installation method in the first modified example, first, a support installation process (step S03), a tank installation process (step S04), an adjustment process (step S05), a closing process ( Step S06) is performed.

Thereafter, a hull side saddle mounting step (step S01) is performed for mounting the saddle 3 to the hull so that the saddle 3 protrudes from the upper deck. Subsequently, a grid material side saddle mounting step (step S02) for mounting the plurality of saddles 3 mounted on the hull to the grid material 4 so that the grid material 4 is supported from below by the plurality of saddles 3 is performed. Finish the installation.
In the first modification, the case where the hull side saddle mounting step (step S01) and the lattice material side saddle mounting step (step S02) are performed after the closing step (step S06) has been described. The closing step (step S06) may be performed after (step S01) and the lattice material side saddle mounting step (step S02). Moreover, although the case where the hull side saddle mounting step (step S01) is performed after the support portion installation step (step S03), the tank installation step (step S04), etc. has been described, the hull side saddle mounting step (step S01) You may make it perform in parallel with a support part installation process (step S03), a tank installation process (step S04), etc.

(Second modification of the embodiment)
FIG. 11 is a flowchart of a tank structure installation method in a second modification of the embodiment of the present invention. In the description of the second modified example, the same steps as those in the above-described embodiment are described with the same reference numerals, and redundant descriptions are omitted.
As shown in FIG. 11, in the tank structure installation method in the second modified example, first, a support portion installation step (step S03), a tank installation step (step S04), an adjustment step (step S05), a closing step ( Step S06) is performed.

  Thereafter, a grid material side saddle mounting step (step S02) for mounting the saddle 3 on the grid material 4 is performed so that the saddle 3 protrudes downward from the grid material 4. Note that the lattice material side saddle mounting step (step S02) in the second modification may be performed before the hull side saddle mounting step (step S01). For example, the support portion installation step (step S03). It may be performed before the tank installation step (step S04) or the like, or may be performed in parallel with the support portion installation step (step S03), the tank installation step (step S04), or the like.

While the assembly (not shown) to which the saddle 3 is attached is lifted by a crane (not shown) or the like, the saddle 3 is attached to a strength member of the hull such as an aggregate provided on the lower surface side of the upper deck 10. A hull side saddle mounting step (step S01) for fixing the tank structure is completed, and the installation of the tank structure is completed. At this time, the saddle 3 is fixed to a hull such as an aggregate so that the lattice material 4 is spaced from the upper deck 10.
In the second modification, the case where the lattice material side saddle mounting step (step S02) and the saddle hull side saddle mounting step (step S01) are performed after the closing step (step S06) has been described. The closing process (step S06) may be performed after the saddle mounting process (step S02) or the saddle hull side saddle mounting process (step S01).

(Third modification)
Next, a third modification of the embodiment of the present invention will be described with reference to the drawings. This third modified example differs from the above embodiment in that the shape of the tank body is a cylindrical shape. Therefore, in this third modification, the same portions as those in the above-described embodiment are described with the same reference numerals, and redundant descriptions are omitted.
As shown in FIG. 12, the tank structure 1B in the third modification includes a saddle 3, a lattice material 4, a support portion 5B, a tank body (cylindrical tank) 6B, and a tank cover 7. . In FIG. 12, only the lower cover 23 of the tank cover 7 is shown, and the upper cover 22 is not shown. The upper cover 22 may have the same shape as the above-described embodiment, or may have another shape corresponding to the tank body 6B.

  The saddle 3 is provided so as to protrude upward from the upper deck 10. A plurality of saddles 3 are provided at intervals, and support the lattice material 4 from below. The saddle 3 illustrated in this embodiment has an H-shaped cross section, and a lower end portion of the saddle 3 is attached to the lower surface of the upper deck 10 and extends in the ship width direction or the bow-stern direction (for example, (Not shown) or the like. Similar to the above-described embodiment, the saddle 3 in the third modification also has a length of about 2 m from the upper deck 10 to its upper end.

  The lattice material 4 is formed in a lattice shape as in the above-described embodiment. The lattice material 4 is supported from below by the plurality of saddles 3 described above. The lattice material 4 includes an outer frame portion 15, a vertical beam portion 16, and a horizontal beam portion 17.

The support portion 5 </ b> B is installed on the upper surface 17 u of the cross beam portion 17 of the lattice material 4. Two support portions 5B exemplified in the third modification are provided at intervals in the extending direction of the longitudinal beam portion 16. The plurality of support portions 5B include a support portion main body 5Ba and a contact portion 5Bb.
The support portion main body 5Ba extends upward from the upper surface 17u of the cross beam portion 17, and has a concave portion 60 corresponding to the shape of the tank main body 6B. The recess 60 in the third modification is formed in an arc shape having a radius of curvature slightly larger than the radius of the tank body 6B when viewed from the extending direction of the longitudinal beam portion 16.

  The contact portion 5Bb is formed in an arc shape along the concave portion 60 when viewed from the direction in which the longitudinal beam portion 16 extends, and is formed in a plate shape extending on both sides in the thickness direction of the support portion main body 5Ba. It is formed so as to contact the tank body 6B. Although not shown, the support portion 5B includes a tank body 6B and a lattice material 4 between the support portion body 5Ba and the contact portion 5Bb, between the contact portion 5Bb and the tank body 6B, and the like. In addition, a heat insulating material made of a material having low thermal conductivity is provided. Examples of the material having lower thermal conductivity than the tank body 6B and the lattice material 4 include synthetic resins such as phenol resin, and wood. In this way, the support portion 5B suppresses heat conduction from the tank body 6B, which is at a very low temperature, to the lattice material 4 while supporting the tank body 6B from below.

  Similarly to the first embodiment, the tank body (tank) 6B accommodates liquefied natural gas (LNG), which is a fuel for navigating the ship. The tank body 6B in this embodiment is a cylindrical tank. The tank body 6B is a spherical surface whose both ends in the direction of the axis O protrude outward. The tank body 6B is supported from below by the plurality of support portions 5B described above. The tank body 6B is formed of a metal such as an aluminum alloy that does not brittlely break against the cryogenic temperature of the liquefied natural gas, as in the above-described embodiment. Further, the tank body 6B is covered with a heat insulating material 40 (see FIG. 8) such as polyurethane, except for the place where it comes into contact with the support portion 5B described above. In addition, in FIG. 12, illustration of the trunk top 21 is abbreviate | omitted.

  For example, a gap is formed between the heat insulating material 40 (not shown) and the tank body 6B, and the tank body 6B extends along the upper deck 10 (not shown) as shown in FIG. In the case of the cylindrical tank main body 6B having the liquefied gas, the leaked liquefied gas moves downward along the outer peripheral surface of the tank main body 6B. Then, they gather at a linear bottom part along the axis O. For example, by providing a pipe or the like (not shown) that reaches a predetermined recess 50A (see FIG. 6) in a part of the lowermost portion, the liquefied gas collected at the lowermost portion is guided to the predetermined recess 50A. Liquefied gas can be stored in the predetermined recess 50A. By providing the pipe or the like in this way, it is not necessary to incline the cylindrical tank 6A in order to collect the liquefied gas at one place.

(Fourth modification)
In the third modification, the case where the tank body 6B is a cylindrical tank has been described. However, other than the cylindrical type, for example, a spherical tank or the like may be used.
Here, the “spherical tank” is not limited to a spherical shape, and has a shape in which the vicinity of the equator is formed in a cylindrical shape or a truncated cone shape, or a shape including an elliptical curved surface in at least a part of the cross section. There may be.

  For example, when a gap is formed between the heat insulating material 40 (not shown) and the spherical tank, the leaked liquefied gas moves to the lowest point along the outer surface of the spherical tank, for example, due to its own weight. Fall. That is, in the case of a spherical tank, the liquefied gas can be stored in the predetermined concave portion 50A if the predetermined concave portion 50A (see FIG. 6) is disposed immediately below the lowest point.

(Other variations)
The present invention is not limited to the configuration of the above-described embodiment and each modification, and can be changed in design without departing from the gist thereof.
For example, in the above-described embodiment, the case where the support portion 5A includes the shim plate 53 under the heat insulating block 20 has been described. However, the shape of the support portion 5A is not limited to the shape of the above-described embodiment as long as it is a structure that can suppress heat transfer between the tank main body 6A and the lattice material 4 and can be adjusted in height.

  Moreover, in embodiment mentioned above, the case where 5 A of support parts were arrange | positioned in the location where the vertical beam part 16 and the horizontal beam part 17 cross | intersect was illustrated. However, the support portion 5A may be provided at a location other than where the vertical beam portion 16 and the horizontal beam portion 17 intersect.

Furthermore, in embodiment mentioned above, the case where fixation of the lattice material 4 with respect to the saddle 3 and fixation of the tank cover 7 with respect to the lattice material 4 was performed was illustrated. However, these fixing methods are not limited to welding, and may be adhesion, for example.
Moreover, the case where the groove part 41 was formed in at least one of the heat insulating material 40 and the tank main body 6A was demonstrated. However, the groove 41 may be provided as appropriate and may be omitted. When the groove 41 is omitted in this manner, for example, a gap may be provided between the heat insulating material 40 and the tank body 6A.

  Furthermore, in the above-described embodiment, the case where the openings 4a of the lattice material 4 are closed from below by the lower cover 23 has been described. However, the configuration is not limited to this configuration as long as the configuration can close the opening 4a. For example, the openings 4a of the lattice material 4 may be closed from above.

In the above-described embodiment and the third and fourth modified examples, the case where the tank bodies 6A and 6B accommodate LNG has been described. However, the liquefied gas stored in the tank bodies 6A and 6B may be LPG or the like.
Moreover, in embodiment mentioned above, the tanker which the ship 2 transports oil was illustrated. However, it is not limited to this ship type. For example, other ship types, such as a liquefied gas carrier ship and a liquefied gas supply ship, may be used.

1A, 1B Tank structure 2 Ship 3 Saddle 4 Grid material 4a Opening 5A, 5B Support section 6A, 6B Tank body (tank)
6a lower surface 7 tank cover 8 hull 9 upper structure 10 upper deck 15 outer frame portion 15a vertical member 15b horizontal member 16 vertical beam portion 17 horizontal beam portion 20 heat insulating block 20a upper surface 21 trunk top 22 upper cover 22a upper wall portion 22b side wall portion 22c opening Edge 23 Lower cover 40 Heat insulating material 41 Groove part 50, 50A Concave part 52 Rib material 53 Shim plate 60 Concave part

Claims (11)

A plurality of saddles spaced apart so as to protrude from the deck of the ship,
A lattice material that is supported by the plurality of saddles from below and forms a lattice shape in plan view,
A plurality of support portions disposed on an upper surface of the lattice material;
A tank that is supported from below by the plurality of support portions, and in which the liquefied gas is stored;
An upper cover supported by the lattice material and covering the side and upper side of the tank;
A plurality of lower covers that form a sealed space together with the upper cover by being attached so as to close the lattice-shaped openings of the lattice material;
Deck placement tank structure equipped with.   The deck placing tank structure according to claim 1 provided with a crevice formed by said lower cover attached so that the opening of said lattice material may be blocked, and said lattice material surrounding said opening, and opening upwards. A heat insulating material covering the surface of the tank;
3. The deck placing tank structure according to claim 2, wherein at least one of the surface of the tank and the heat insulating material includes a groove portion that guides the liquefied gas leaked from the tank to the concave portion. The support part is
A heat insulating block having a lower thermal conductivity than the tank and the lattice material;
A height adjusting member for adjusting the height of the upper surface of the heat insulating block;
The deck placing tank structure according to any one of claims 1 to 3 provided with.   The deck according to any one of claims 1 to 4, wherein the tank has any one of a rectangular tank, a cylindrical tank, and a spherical tank, and contains LNG or LPG as the liquefied gas. Place tank structure.   A ship provided with the deck placing tank structure according to any one of claims 1 to 5. A support portion installation step of installing a plurality of support portions on the upper surface of the lattice material that forms a lattice shape in plan view;
A tank installation step in which a tank in which liquefied gas is stored is installed on the support portion so as to be supported from below by the plurality of support portions;
An adjustment step of adjusting a clearance between the support portion and the tank through a lattice-shaped opening of the lattice material;
A closing step of sealing a lattice-shaped opening of the lattice material with a lower cover;
A hull side saddle mounting step of mounting a plurality of saddles supporting the lattice material from below on the hull;
A grid material side saddle mounting step of mounting the plurality of saddles to the grid material;
How to install the tank including   The tank installation method according to claim 7, wherein the grid material side saddle mounting step is performed after the hull side saddle mounting step.   The tank installation method according to claim 7, wherein the hull side saddle mounting step is performed after the lattice material side saddle mounting step.   The tank installation method according to claim 9, wherein the hull side saddle mounting step is performed at least after the support portion installation step and the tank installation step. A plurality of saddles spaced apart so as to protrude from the deck of the ship,
A lattice material that is supported by the plurality of saddles from below and forms a lattice shape in plan view,
A plurality of support portions disposed on an upper surface of the lattice material;
A tank that is supported from below by the plurality of support portions, and in which the liquefied gas is stored;
An upper cover supported by the lattice material and covering the side and upper side of the tank;
A plurality of lower covers that form a sealed space together with the upper cover by being attached so as to close a lattice-shaped opening of the lattice material, and an inspection method for a deck tank structure comprising:
A lower cover removing step of removing a part of the lower cover from the lattice material among the plurality of lower covers attached to close the lattice-shaped openings of the lattice material;
An inspection step of inspecting the inside of the sealed space through the opening from which the lower cover is removed;
A re-closure step of re-sealing the opening by the lower cover removed in the lower cover removal step;
Including inspection method.

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