Ship structure

Abstract

A ship structure is provided that enables inspection of welded portions that become critical points in bilge tanks without incurring a large amount of expense on inspection equipment. A side girder (31) is provided along the welded portion between the first connecting edge (29Ac) of the first transverse web member (29A) and the second connecting edge (29Ba) of the second transverse web member (29B) in the transverse web (29). A window hole (33) for inspection is formed in the side girder (31). The window hole (33) is used to allow an inspection worker (M) to inspect the welded portion between the inclined inner edge (29Ab) and the straight inner edge (29Bc), which become the critical point (CP) for endurance inspection, while lying prone on the side girder (31).

Description

Technical Field

[0001] The present invention relates to a ship structure capable of performing spot inspection of welded portions serving as critical points in a bilge hopper tank. Background Art

[0002] Japanese Patent Application Laid-Open No. 5-278674 (Patent Document 1) discloses prior art related to inspection equipment within ballast tanks of marine structures. This publication describes conventional methods for performing in-tank inspections using a small boat system and a full-scale scaffolding system. The small boat system involves loading a rubber boat into the tank and using a ballast pump to adjust the tank's liquid level, thereby moving the boat up and down. The full-scale scaffolding system, on the other hand, involves sequentially erecting scaffolding from the tank roof toward the construction site. However, the small boat system suffers from drawbacks such as the need to be able to adapt to changes in ballast depth while the vessel is floating, limiting the repair and inspection area. Furthermore, while inspections from a small boat are possible within the tank, they are unstable and impractical. In particular, in the case of double-hulled oil tankers, the narrow width of the side ballast tanks makes it difficult to accommodate and float a small boat. Furthermore, the full-scale scaffolding method requires numerous skilled scaffolders to erect scaffolding within the cabin. Furthermore, erecting and removing the scaffolding is an extremely dangerous operation. Therefore, the inspection work technique described in Patent Document 1 provides openings of a desired size at the upper ends of each transverse disposed between the outer and inner shells, and also provides girder openings of a desired size in the horizontal girders disposed between the inner and outer shells, to enable ongoing inspection work. Furthermore, the proposed inspection structure includes travel rails provided in the ceiling of the openings disposed at the upper ends of the transverses. A hoist, with a suspended basket, is supported on these travel rails so as to be freely movable, allowing the basket to move along the travel rails within the opening. In this structure, after the movement of the hoist is stopped, the rope for suspending the basket is released from the hoist, and the basket is lowered while passing through the girder opening. The basket is stopped at an arbitrary location to perform necessary inspections and repairs.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 5-278674 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] In the past, the inspection was performed by using special equipment such as boats, scaffolds, and hanging baskets, taking into account the operator's workability and the condition of the wet cabin. However, due to these considerations, a lot of cost and time were spent on the inspection equipment.

[0008] An object of the present invention is to provide a ship structure that allows safe and easy inspection of welded portions, which are critical points, in a bilge slop tank without consuming a large amount of cost and time on inspection equipment.

[0009] Solutions to Problems

[0010] In the following description, reference numerals are used in the accompanying drawings for easier understanding. The present invention relates to a ship structure comprising a bilge sloping tank disposed between an outer hull and an inner hull, a plurality of transverse webs spaced apart in the longitudinal direction of the hull within the bilge sloping tank, and a plurality of side longitudinal girders disposed between two adjacent transverse webs and spaced apart in the vertical direction. Moreover, the transverse web comprises a first transverse web member and a second transverse web member, the first transverse web member having: a first outer edge portion, which is arranged across the side wall and bottom wall of the outer shell of the hull and is welded to the inner surface of the outer shell; an inclined inner edge portion, which is opposite to the first outer edge portion and is inclined in such a manner that the distance between the inclined inner edge portion and the bottom wall becomes smaller as it approaches the center of the ship; and a first connecting edge portion, which extends in a horizontal direction and connects the first outer edge portion to the inclined inner edge portion, the second transverse web member having: a second connecting edge portion, which is welded to the first connecting edge portion of the first transverse web member; a second outer edge portion, which extends in an up-down direction and is welded to the side wall of the outer shell; and a straight inner edge portion, which is opposite to the second outer edge portion and extends in a straight line in the up-down direction.

[0011] In the present invention, a side girder is provided along the welded portion between the first and second connecting edges. Furthermore, an inspection window is formed in the side girder. This inspection window allows an inspection operator to inspect the welded portion between the inclined inner edge and the straight inner edge, which serves as a critical point for endurance inspection, while lying facedown on the side girder. Prior to the inspection, the tank is cleaned in accordance with ship classification regulations, allowing the inspection operator to lie facedown around the inspection window. The inspection operator, lying facedown on the side girder, then passes through the inspection window and brings the inspection equipment close to the welded portion, thereby facilitating inspection of the critical welded portion. Consequently, according to the present invention, inspection of the critical welded portion within the bilge sloping tank can be performed safely and easily without incurring significant costs and time consuming on inspection equipment.

[0012] The inspection window is preferably formed of a long hole formed along the second connecting portion of the second transverse web member at a position where the inspection of the welded portion can be performed without affecting the strength of the welded portion serving as a critical point.

[0013] The inspection window hole is of course of a size that allows inspection work to be carried out through the inspection window hole. In addition, the inspection window hole is preferably of a size that allows the inspection work to be carried out by placing the head of the inspection worker through the inspection window portion under the side longitudinal girder. If the inspection work can be carried out with the head of the inspection worker placed under the side longitudinal girder, visual confirmation can be carried out without having to adopt an awkward posture. In addition, if the inspection window hole is a long hole, it is easy to ensure the range of the inspection worker's hands when placing the hands and head of the inspection worker under the side longitudinal girder to carry out the inspection work. In addition, even if the inspection worker is equipped with inspection equipment such as a hard hat and a dust mask required for inspection inside the cabin, confirmation can be easily carried out.

[0014] In addition, a hanging rod for hanging a safety belt worn by an inspection worker is fixed to the longitudinal through rib member closest to the side longitudinal girder among the multiple longitudinal rib members adjacent to the straight inner edge and passing through the second transverse web member. By hanging the safety belt on the hanging rod, the inspection worker can be prevented from falling through the inspection window hole and can be prevented from accidentally falling into the inspection window hole when passing through the side longitudinal girder. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic perspective view showing an example of a tanker ship structure in a partially broken state.

[0016] Figure 2 It will Figure 1 A perspective view showing a state in which a part of the main part is enlarged and perspective.

[0017] Figure 3 yes Figure 1 An enlarged view of the main part.

[0018] Figure 4 This is a diagram showing the state when an inspection worker is inspecting a critical point.

[0019] Figure 5 It is a diagram for explaining the details of the inspection window.

[0020] Figure 6 This is a diagram showing an example of a state in which an inspection worker wears inspection equipment.

[0021] Description of reference numerals:

[0022] 1 Ship structure

[0023] 1A housing

[0024] 1B inner shell

[0025] 1C Bilge sloping tank

[0026] 3 Double bottom

[0027] 5 Double-decker ship sidewall

[0028] 7-cabin unit

[0029] 9. Bottom shell

[0030] 11 Inner bottom hull

[0031] 13 Ship side shell

[0032] 15 Ship side inner hull

[0033] 16 Middle inner wall

[0034] 17 Length Next Door

[0035] 23 Central Compartment

[0036] 25a, 25b side tanks

[0037] 29 transverse web

[0038] 29A First transverse web member

[0039] 29B Second transverse web member

[0040] 31 side stringer

[0041] 33 Inspection window

[0042] 35 longitudinal ribs

[0043] 37 hanging rod. DETAILED DESCRIPTION

[0044] Hereinafter, an example of an embodiment of the ship structure of the present invention will be described in detail with reference to the drawings.

[0045] Figure 1 This is a simplified perspective view showing an example of a tanker ship structure with a portion broken off. Figure 2 It will Figure 1 A perspective view of a portion of the bilge tank in an enlarged and perspective state. Figure 1 and Figure 2As shown, the ship structure 1 of this embodiment generally has a bilge tank 1C between an outer hull 1A and an inner hull 1B. Specifically, the ship structure 1 is a double-hull structure having a double bottom 3 and double sidewalls 5, and has a structure in which a plurality of tank units 7 are arranged in the traveling direction (D1) of the tanker. Transverse bulkheads (not shown) are provided at both ends of each tank unit 7 in the traveling direction. Figure 1 One cabin unit 7 is shown.

[0046] The tank unit 7 includes a bilge sloping tank 1C in the width direction, which is composed of two side tanks 25a and 25b and a center tank 23. Each tank 23, 25a, 25b is filled with a fluid such as heavy oil to be transported. Figure 1 The illustrated first direction D1 represents the tanker's travel direction, the second direction D2, perpendicular to the travel direction, represents the width direction, and the third direction D3, perpendicular to both the first and second directions D1 and D2, represents the vertical direction. In this embodiment, each tank unit 7 has a longitudinal dimension L (the distance between the two transverse bulkheads) of approximately 50 meters, a width dimension W (the distance between the side hulls 13 and 13) of approximately 60 meters, and a height dimension H (the distance from the bottom hull 9 to the deck 21) of approximately 29 meters.

[0047] The double bottom 3 is composed of an outer bottom hull 9 and an inner bottom hull 11, while the double sidewalls 5 are composed of an outer side hull 13 and an inner side hull 15. The outer bottom hull 9 and the outer side hull 13 constitute the outer hull 1A, while the inner bottom hull 11 and the inner side hull 15 constitute the inner hull 1B. An intermediate inner wall 16 extends between the inner bottom hull 11 and the inner side hull 15, connecting them. While the thickness of the outer and inner hulls is not shown in the figure for constructional reasons, the steel plates forming the hull are approximately 18.5 mm thick. The interior spaces of the double bottom 3 and the double sidewalls 5 function as ballast tanks for ballast water. One tank unit 7 is composed of one central tank 23 and two side tanks 25a, 25b, which are surrounded by the bottom inner hull 11, the side inner hull 15, two longitudinal bulkheads 17, 17 extending along the travel direction (first direction) D1 and spaced apart in the width direction (second direction) D2, two transverse bulkheads (not shown) extending along the width direction D2 perpendicular to the travel direction D1, and the deck 21. Figure 1 In the figure, the internal structures of the center tank 23 and the two side tanks 25a and 25b are omitted.

[0048] In the center tank 23 , a plurality of vertical webs 27 are provided at regular intervals along the two longitudinal bulkheads 17 , 17 in the traveling direction D1 . The plurality of vertical webs 27 are connected to the longitudinal bulkheads 17 , the bottom inner hull 11 , and the deck 21 .

[0049] Within the double bottom 3 and double sidewalls 5 of the tank unit 7, multiple transverse webs 29 are spaced apart in the traveling direction, corresponding to each wing tank 25a or 25b, and are connected to the outer bottom shell 9, the inner bottom shell 11, the outer side shell 13, and the inner side shell 15 (in this embodiment, also connected to the intermediate inner wall 16). The transverse webs 29 are composed of a first transverse web member 29A connected to the outer side shell 13, the inner side shell 15, and the intermediate inner wall 16 and having a through-hole in its center for weight reduction; a second transverse web member 29B connected to the outer side shell 13 and the inner side shell 15; a third transverse web member 29C on the wing tank side, connected to the outer bottom shell 9 and the inner bottom shell 11; and a fourth transverse web member 29D on the center tank side. In this specification, these first to fourth transverse web members 29A-29D are collectively referred to as a single transverse web 29. It should be noted that one vertical web 27 and one transverse web 29 are respectively provided at positions facing each other in the width direction. In addition, between two adjacent transverse webs 29, a plurality of side longitudinal girders 31 are provided, welded to the two adjacent transverse webs 29 and arranged at intervals in the vertical direction.

[0050] The first transverse web member 29A and the second transverse web member 29B will be described in more detail. First, the first transverse web member 29A includes at least a first outer edge portion 29Aa extending across the bottom outer shell 9 and the side outer shell 13 (the bottom and side walls of the outer shell 1A) and welded to the inner surfaces of the bottom outer shell 9 and the side outer shell 13; an inclined inner edge portion 29Ab facing the first outer edge portion 29Aa and welded to the intermediate inner wall 16 at an angle such that the distance between the inclined inner edge portion 29Ab and the bottom outer shell 9 (the bottom wall of the outer shell 1A) decreases toward the center of the vessel; and a first connecting edge portion 29Ac extending horizontally and connecting the first outer edge portion 29Aa and the inclined inner edge portion 29Ab. In addition, the second transverse web member 29B has at least: a second connecting edge 29Ba, which is welded to the first connecting edge 29Ac of the first transverse web member 29A; a second outer edge 29Bb, which extends in the up-down direction and is welded to the ship side outer shell 13 of the outer shell 1A; and a straight inner edge 29Bc, which is opposite to the second outer edge 29Bb and extends in a straight line in the up-down direction and is welded to the ship side inner shell 15.

[0051] In this embodiment, one side longitudinal girder 31 is provided along the welded portion between the first connecting edge 29Ac and the second connecting edge 29Ba. Figures 2 to 4 As shown, a spot inspection window 33 is formed on the side longitudinal girder 31. The spot inspection window 33 is used to allow the inspection worker M to inspect the welded portion between the inclined inner edge 29Ab and the straight inner edge 29Bc, which is the critical point CP for endurance inspection, while lying face down on the side longitudinal girder 31. Figure 5 As shown, the inspection window 33 is preferably formed by a long hole formed along the second connecting edge 29Ba of the second transverse web member 29B at a position that does not affect the endurance of the welded portion serving as the critical point CP and enables inspection of the welded portion. Figure 5 As shown, the shape of the long hole is preferably such that the length of the major axis is 450 mm and the length of the minor axis is approximately 350 mm. With this size, the inspection worker can perform inspection work through the inspection window 33, and can perform inspection work with the worker's head positioned under the side longitudinal girder 31 through the inspection window. If the inspection work can be performed with the worker's head positioned under the side longitudinal girder 31, visual confirmation is possible without adopting an awkward posture. Furthermore, if the inspection window is such a long hole, it is easy to ensure a range for the worker's hand to move when the worker's hand or head is positioned under the side longitudinal girder 31 to perform inspection work.

[0052] exist Figure 6 , shows an example of the equipment worn by an inspection worker M. The inspection worker M wears a safety belt SB around his waist, holds an illuminated magnifying glass HG in his left hand, a thickness gauge TI in his right hand, and a headlamp HL on his helmet. Furthermore, in this embodiment, a hanger 37 for hooking the mounting bracket of the safety belt SB worn by the inspection worker M is fixed to the longitudinal rib 35 closest to the side longitudinal girder 31, among the plurality of longitudinal ribs adjacent to the linear inner edge 29Bc and penetrating the second transverse web member 29B. This allows the hanger 37 to be fixed at a preferred position using the longitudinal rib 35.

[0053] Before the inspection, although the side longitudinal girder 31 is in a wet state, the inspection worker M can lie prone around the inspection window 33 by cleaning the cabin according to the ship classification rules. Figure 4 As shown, after hooking the attachment of the safety belt SB onto the hook rod 37, the inspection worker M lies prone on the side girder 31 and passes through the inspection window 33. The inspection worker M brings the inspection equipment (HG, TI) close to the welded portion, making it easier to inspect the welded portion, which serves as the critical point CP. This makes it possible to inspect the welded portion, which serves as the critical point CP, within the bilge sloping tank 1C without spending a lot of money and time on inspection equipment.

[0054] In the above embodiment, the present invention is applied to a double-hull tanker. However, the present invention is applicable to any ship regardless of its size as long as it includes a web plate and side girders having a critical point.

[0055] Industrial Applicability

[0056] According to the present invention, it is possible to safely perform inspection of welded portions serving as critical points in a bilge slop tank without consuming a large amount of cost and time on inspection equipment.

Claims

1. A ship structure comprising: Bilge sloping tank, which is located between the outer hull and the inner hull; a plurality of transverse webs arranged at intervals in the bilge sloping tank in the longitudinal direction of the hull; A plurality of side longitudinal girders are arranged between two adjacent transverse webs and spaced apart in the vertical direction. The transverse web comprises a first transverse web member and a second transverse web member, The first transverse web member comprises at least: a first outer edge portion, which is provided across the side wall and the bottom wall of the outer shell of the hull and is welded to the inner surface of the outer shell; an inclined inner edge portion, which is opposite to the first outer edge portion and is inclined in such a manner that the distance between the inclined inner edge portion and the bottom wall becomes smaller as it approaches the center of the hull; and a first connecting edge portion, which extends in the horizontal direction and connects the first outer edge portion and the inclined inner edge portion; The second transverse web member includes: a second connecting edge portion welded to the first connecting edge portion of the first transverse web member; a second outer edge portion extending in the vertical direction and welded to the side wall of the shell; and a linear inner edge portion opposite to the second outer edge portion and extending linearly in the vertical direction. The ship structure is characterized in that: One of the side longitudinal girder is provided along a welded portion between the first connecting edge portion and the second connecting edge portion. An inspection window is formed on the side longitudinal girder, and the inspection window is used to allow an inspection worker to inspect the welded portion between the inclined inner edge portion and the straight inner edge portion, which is a critical point for endurance inspection, while lying prone on the side longitudinal girder.

2. The ship structure according to claim 1, wherein: The inspection window has a size that allows inspection work to be performed through the inspection window.

3. The ship structure according to claim 1, wherein: The inspection window has a size that allows the inspection worker to perform the inspection work in a state where the head of the inspection worker is placed under the side girder through the inspection window.

4. The ship structure according to claim 2 or 3, wherein: The inspection window hole is constituted by a long hole formed along the second connecting edge portion of the second transverse web member at a position where the inspection of the welded portion is possible without affecting the endurance of the welded portion.

5. The ship structure according to any one of claims 1 to 3, wherein: A hanging rod for hooking a mounting fitting of a safety belt worn by the inspection worker is fixed to the longitudinal frame closest to the side longitudinal girder among the plurality of longitudinal frames adjacent to the linear inner edge portion and penetrating the second transverse web member.

6. The ship structure according to claim 4, wherein: A hanging rod for hooking a mounting fitting of a safety belt worn by the inspection worker is fixed to the longitudinal frame closest to the side longitudinal girder among the plurality of longitudinal frames adjacent to the linear inner edge portion and penetrating the second transverse web member.

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