Mutually lifting system and working radius adjustment member

Abstract

To mutually lift even a heavy member with a first crane and a second crane.SOLUTION: A mutual lifting system 1 includes a first crane 10, a second crane 20, and a member to be lifted TP that is mutually lifted by the first crane 10 and the second crane 20, and further includes a working radius adjustment member 30 interposed between the first crane 10 and the second crane 20, and the member to be lifted TP, where the working radius adjustment member 30 can reduce a working radius of each of the first crane 10 and the second crane 20, and where the working radius adjusting member 30 includes a reinforcing portion for reinforcing each portion of the working radius adjusting member 30.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a hoisting system and an operating radius adjustment member. [Background technology]

[0002] Conventionally, a workpiece to be lifted has been hoisted by two cranes in tandem. Patent document 1 discloses that the workpiece to be lifted is suspended horizontally by a wire rope which is attached to two blocks fixed to the top surface of the frame of a lifting beam, and the suspension parts at both ends of the frame are hoisted by the hooks of two cranes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 57-27889 Summary of the Invention [Problem to be solved by the invention]

[0004] However, Patent Document 1 does not anticipate reducing the working radius of the two cranes.

[0005] The present disclosure has been made in consideration of the above-mentioned circumstances, and has an object to provide a co-lifting system and working radius adjustment member that enables the lifting capacity of the first crane and the second crane to be improved by reducing the working radius of each of the first and second cranes, thereby enabling the first and second cranes to hoist even a heavy lifted object together. [Means for solving the problem]

[0006] The mutual hoisting system of the present disclosure is a mutual hoisting system comprising a first crane, a second crane, and a lifted member that is mutually hoisted by the first crane and the second crane, and further comprising an working radius adjustment member interposed between the first crane, the second crane, and the lifted member, wherein the working radius adjustment member is capable of reducing the working radius of each of the first crane and the second crane, and the working radius adjustment member includes a reinforcing portion for reinforcing each portion of the working radius adjustment member. Effect of the Invention

[0007] According to the present disclosure, it is possible to provide a co-lifting system and a working radius adjustment member that enable co-lifting by a first crane and a second crane even when the lifted object is heavy. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of a suspension system according to an embodiment. [Diagram 2] FIG. 2 is an enlarged view of part II in FIG. [Diagram 3] FIG. 3 is a side view of FIG. 2. [Figure 4] FIG. 3 is a plan view of FIG. 2. [Diagram 5] FIG. 2 is a perspective view showing a state in which the hoisting frame is hoisted by a first crane and a second crane. [Figure 6] FIG. 5 is a plan view showing a second example of the hanging frame, and corresponds to FIG. [Figure 7] FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG. [Figure 8] FIG. 8 is a cross-sectional view taken along the line VIII-VIII in FIG. 6. [Figure 9] FIG. 11 is a diagram showing a second example of a connection structure between a suspension frame and a transition piece. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a suspension system and a suspension method according to one embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of a suspension system 1 according to an embodiment. FIG. 1 shows a jacket-type foundation in the process of being manufactured. The jacket-type foundation supports the tower of an offshore wind turbine (not shown). FIG. 1 shows the process of assembling the jacket-type foundation in a yard Y on the ground. In FIG. 1, the jacket-type foundation in the process of being manufactured (hereinafter also referred to as the lower jacket J) includes a lower leg UL and a brace BR. A plurality of lower legs UL are provided. A plurality of lower legs UL are provided at intervals around the central axis of the lower jacket J (hereinafter also referred to as the circumferential direction). The central axis of the lower jacket J extends in the vertical direction. The central axis of the lower jacket J coincides with, for example, the central axis of a center pipe TP4 of a transition piece TP described later. The lower leg UL is inclined so as to move away from the central axis of the lower jacket J as it goes downward. The lower end of the lower leg UL is supported by a dolly D (transportation vehicle). The brace BR connects the lower legs UL adjacent to each other in the circumferential direction.

[0010] As shown in FIG. 1, the hoisting system 1 according to this embodiment includes a transition piece TP (a member to be hoisted), a first crane 10, a second crane 20, and a hoisting frame 30 (a working radius adjustment member).

[0011] The transition piece TP is provided on the jacket-type foundation. The transition piece TP is installed on the lower jacket J. In the co-hoisting system 1, the transition piece TP is co-hoisted by a first crane 10 and a second crane 20, as shown in FIG. 1. As a result, the transition piece TP is placed on the upper part of the lower leg UL from the yard Y and fixed to the lower jacket J. The jacket-type foundation produced in this manner is transported from the yard Y and placed offshore. In the jacket-type foundation placed offshore, the lower end of the tower of the offshore wind turbine is connected to the transition piece TP. As a result, the tower of the offshore wind turbine is supported by the jacket-type foundation on which the transition piece TP is provided.

[0012] FIG. 2 is an enlarged view of part II in FIG. FIG. 3 is a side view of FIG. FIG. 4 is a plan view of FIG. As shown in FIGS. 2 to 4, the transition piece TP includes an upper plate TP1, a lower plate TP2, a web TP3, a center pipe TP4, a leg TP5, and a hanging piece TP7.

[0013] The upper plate TP1 is disposed horizontally above the transition piece TP. In this embodiment, the horizontal direction is, for example, a direction parallel to the sea surface on which the offshore wind turbine is disposed. As shown in Fig. 4, the upper plate TP1 is cross-shaped in a plan view, with a center pipe TP4 disposed in the center and legs TP5 disposed at each end of the cross.

[0014] As shown in Fig. 2, the lower plate TP2 is disposed horizontally at the lower end of the transition piece TP. As shown in Fig. 4, the lower plate TP2, like the upper plate TP1, is cross-shaped in plan view, with a center pipe TP4 disposed in the center and legs TP5 disposed at each end of the cross. In this way, the transition piece TP supports the center pipe TP4 and the legs TP5 at two locations, one above and one below. In this embodiment, the lower plate TP2 is larger than the upper plate TP1 in plan view.

[0015] The web TP3 is a member that reinforces the area between the upper plate TP1, the lower plate TP2, the center pipe TP4, and the leg TP5. As shown in Fig. 2, the web TP3 is a plate having a substantially rectangular shape. The four sides of the web TP3 connect to the upper plate TP1, the lower plate TP2, the center pipe TP4, and the leg TP5, respectively. In this way, the web TP3 reinforces the transition piece TP.

[0016] The center pipe TP4 is a cylindrical member and is disposed in the center of the transition piece TP. The center pipe TP4 is supported by an upper plate TP1, a lower plate TP2, and a web TP3. In this embodiment, the lower end of the tower of the offshore wind turbine (not shown) is connected to the center pipe TP4. In this way, the transition piece TP supports the offshore wind turbine.

[0017] The leg TP5 is a cylindrical member disposed between the upper plate TP1 and the lower plate TP2. In this embodiment, the leg TP5 is provided at each end of the cross shape of the upper plate TP1 and the lower plate TP2, as shown in Fig. 4. That is, in this embodiment, four legs TP5 are provided. In this embodiment, as shown in Fig. 2, the leg TP5 is inclined so as to move away from the center pipe TP4 as it goes from top to bottom. When the transition piece TP is disposed in the lower jacket J, the lower end of the leg TP5 is connected in a state of being aligned with the upper end of the lower leg UL. At this time, the lower plate TP2 may be disposed between the lower end of the leg TP5 and the upper end of the lower leg UL. When the leg TP5 protrudes downward from the lower plate TP2 (when the leg TP5 is a through member with respect to the lower plate TP2), the lower end of the leg TP5 may be disposed (joined) directly to the upper end of the lower leg UL. Hereinafter, one of the four legs TP5 will be referred to as a first leg TP5a as shown in Fig. 4. The other legs TP5 will be referred to as a second leg TP5b, a third leg TP5c, and a fourth leg TP5d in a clockwise direction starting from the first leg TP5a in a plan view of the transition piece TP. Hereinafter, when there is no need to distinguish between these legs, they will be referred to as legs TP5.

[0018] As shown in Figures 2 to 4, the hanging piece TP7 is used when the transition piece TP is lifted by the first crane 10 and the second crane 20. The hanging piece TP7 is, for example, a plate-shaped member with a through hole in the center. The hanging piece TP7 is provided on the upper surface of the upper plate TP1. The hanging piece TP7 is attached to the upper surface of the upper plate TP1 by, for example, welding.

[0019] In this embodiment, at least one or more suspension pieces TP7 are provided in the transition piece TP. The at least one or more suspension pieces TP7 are connected to the first crane 10 and the second crane 20. As shown in Fig. 4, in this embodiment, at least four or more suspension pieces TP7 are provided, and the at least four or more suspension pieces TP7 are provided radially around the center of the transition piece TP. The number of the hanging pieces TP does not have to be four or more, and may be one, two, or three, for example. For example, when lifting a structure that is point-symmetric in a planar view, such as a transition piece TP, it is preferable to arrange the hanging pieces TP7 in a position that is point-symmetric. However, for example, when lifting a member to be lifted that is asymmetric in a planar view, the hanging pieces TP7 do not have to be arranged point-symmetrically. In any case, it is preferable that the hanging pieces TP7 are provided so that the center of gravity of the member to be lifted (load) is inside the hanging frame 30 in a planar view when the hanging frame 30 is connected to the hanging piece TP7.

[0020] In this embodiment, the hanging pieces TP7 include a first hanging piece TP7a, a second hanging piece TP7b, a third hanging piece TP7c, and a fourth hanging piece TP7d. In other words, in this embodiment, four hanging pieces TP7 are provided. Hereinafter, when there is no need to distinguish between these hanging pieces, they will be referred to as hanging pieces TP7.

[0021] The first hanging piece TP7a is provided on the upper surface of the upper plate TP1, between the first leg TP5a and the pipe axis of the center pipe TP4. In this embodiment, the first hanging piece TP7a may be provided so as to be inserted into an external work floor (not shown). The external work floor may be provided on the upper surface of the upper plate TP1. On the external work floor, workers can stand and perform various operations on the manufactured (completed) transition piece TP. The second hanging piece TP7b is provided on the upper surface of the upper plate TP1 between the second leg TP5b and the pipe axis of the center pipe TP4. In this embodiment, the second hanging piece TP7b is provided so as to be inserted into the external work floor. The third hanging piece TP7c is provided on the upper surface of the upper plate TP1, between the third leg TP5c and the axis of the center pipe TP4. The fourth hanging piece TP7d is provided on the upper surface of the upper plate TP1, between the fourth leg TP5d and the axis of the center pipe TP4. In this embodiment, each of the four hanging pieces TP7 described above is preferably provided on the upper surface of the upper plate TP1, at least on the side closer to the leg TP5 between the leg TP5 and the axis of the center pipe TP4. This makes it preferable to widen the intervals between the hanging pieces TP7 on the upper surface of the upper plate TP1. This makes it possible to, for example, reduce the effect of the difference in the height at which the transition piece TP is hoisted by the first crane 10 and the second crane 20, making it easier to keep the transition piece TP horizontal.

[0022] As shown in Fig. 1, the first crane 10 and the second crane 20 hoist the transition piece TP together. That is, in this embodiment, when lifting the transition piece TP, the transition piece TP is lifted simultaneously by the first crane 10 and the second crane 20. This makes it possible to lift the heavy transition piece TP by the first crane 10 and the second crane 20, which have relatively low lifting capacity. In the present embodiment, as shown in FIG. 1, the first crane 10 and the second crane 20 are arranged to face each other with the pipe axis of the center pipe TP4 of the transition piece TP interposed therebetween. Hereinafter, the direction along the horizontal direction and along the straight line connecting the first crane 10 and the second crane 20 is referred to as the first direction D1. The direction along the horizontal direction and orthogonal to the first direction D1 is referred to as the second direction D2. In the present embodiment, as shown in FIG. 4, the first crane 10 and the second crane 20 are located above a straight line passing through the central axis of the lower jacket J in a plan view and not passing through the leg TP5 of the lower jacket J.

[0023] As shown in FIG. 1, known ones are preferably used for the first crane 10 and the second crane 20. The first crane 10 and the second crane 20 may be installed, for example, in a ground yard Y or on a crane ship. That is, the tandem lifting system 1 according to the present embodiment may be provided on the ground or on the sea. In other words, the tandem lifting according to the present embodiment may be performed on the ground or on the sea. In the illustrated example, both the first crane 10 and the second crane 20 are self-propelled cranes traveling on the yard Y. Note that the first crane 10 and the second crane 20 do not have to be the same type of crane, and the lifting capacity of the first crane 10 and the lifting capacity of the second crane 20 may be different. In the present embodiment, as shown in FIG. 1, the hook, lifting wire, boom, and vehicle body of the first crane 10 are referred to as a first hook 11, a first lifting wire 12, a first boom 13, and a first vehicle body 14, respectively. The hook, lifting wire, boom, and vehicle body of the second crane 20 are referred to as a second hook 21, a second lifting wire 22, a second boom 23, and a second vehicle body 24, respectively. In the present embodiment, the four above-described lifting pieces TP7 are respectively connected to the first crane 10 and the second crane 20. This enables the transition piece TP to be tandem-lifted by the first crane 10 and the second crane 20.

[0024] It is preferable that the position of the first crane 10 is almost point-symmetrical with the position of the second crane 20 across the transition piece TP. Here, for example, the central axis of the lower jacket J can be used as a reference for this point symmetry. In addition, the above-mentioned almost point symmetrical is not limited to the case where, for example, the position of the base end (first vehicle body 14) of the first boom 13 of the first crane 10 and the position of the base end (second vehicle body 24) of the second boom 23 of the second crane 20 are completely point-symmetrical. For example, there may be a difference of about 10% between the distance from the central axis of the lower jacket J to the first vehicle body 14 and the distance from the central axis of the lower jacket J to the second vehicle body 24. For example, the central angle around the central axis of the lower jacket J between the first vehicle body 14 and the second vehicle body 24 may be different by about 10% from 180°.

[0025] (Hanging frame) FIG. 5 is a perspective view showing a state in which the hoisting frame 30 is hoisted by the first crane 10 and the second crane 20. As shown in FIG. As shown in FIG. 1 to FIG. 5, the hoisting frame 30 is interposed between the first crane 10 and the second crane 20 and the transition piece TP. In this embodiment, the hoisting frame 30 is disposed between the first crane 10 and the second crane 20 and the hoisting piece TP7. In the illustrated example, the hoisting frame 30 is a frame-shaped member, but may be, for example, a beam (hoisting beam). The hoisting frame 30 can reduce the working radius of each of the first crane 10 and the second crane 20, and is provided to reduce the working radius. That is, the hoisting frame 30 is provided to make the first boom 13 and the second boom 23 closer to the vertical than when the first crane 10 and the second crane 20 are directly connected to the hoisting piece TP7 (details will be described later). The fact that the hoisting frame 30 is capable of reducing the working radius of each of the first crane 10 and the second crane 20 means that, for example, when comparing (1) a case in which the first crane 10 and the second crane 20 are directly connected to the transition piece TP (hoisting piece TP7) with (2) a case in which the hoisting frame 30 is interposed between the first crane 10 and the second crane 20 and the transition piece TP, the working radius is smaller in the case (2).

[0026] Two examples of the specific structure of the hanging frame 30 will be described below.

[0027] (First example of a hanging frame) As shown in Figures 2 to 5, the first example of the suspension frame 30 is formed into a substantially rectangular parallelepiped shape by combining beam-like members and column-like members. As shown in Figure 2, the thickness of the suspension frame 30 is thicker at the center in the longitudinal direction than at both ends in the longitudinal direction. By using such a shape, the load is sufficiently distributed when the transition piece TP is suspended via the suspension frame 30. As shown in FIG. 5, the suspension frame 30 includes a lower surface portion 31, an upper surface portion 32, a connection portion 33, and a reinforcing portion .

[0028] As shown in Fig. 5, the lower surface portion 31 is located below the hanging frame 30. The lower surface portion 31 is formed in a rectangular shape by combining beam-like members. The lower surface portion 31 is a portion of the hanging frame 30 that is located at the lower end, and forms the lower surface of the hanging frame 30. The lower surface portion 31 is a rectangular frame body. The upper surface portion 32 is located above the hanging frame 30. The upper surface portion 32 is formed in a rectangular shape by combining beam-shaped members. The upper surface portion 32 is a portion located at the upper end of the hanging frame 30, and forms the upper surface of the hanging frame 30. The upper surface portion 32 is a rectangular frame body. The length of the hanging frame 30 in the first direction D1 is constant from the lower end to the middle in the vertical direction of the hanging frame 30, and gradually decreases from the middle to the upper end in the vertical direction. In this way, the upper end of the hanging frame 30 is narrower in the first direction D1 than the lower end of the hanging frame 30, and the length of the short side of the upper surface portion 32 is the same as that of the lower surface portion 31, and the length of the long side is shorter than that of the lower surface portion 31.

[0029] The connection portion 33 connects the lower surface portion 31 and the upper surface portion 32. The connection portion 33 connects the corners of the lower surface portion 31 and the upper surface portion 32. Four connection portions 33 are provided corresponding to the corners. When viewed from the second direction D2, the connection portion 33 is in a shape of a horizontally laid L. The connection portion 33 includes a vertical portion 33a and an oblique portion 33b. The vertical portion 33a extends in a direction perpendicular to the rectangular lower surface portion 31 and the upper surface portion 32. The vertical portion 33a is provided at the four corners of the lower surface portion 31. The oblique portion 33b is disposed obliquely with respect to the lower surface portion 31 and the upper surface portion 32. The oblique portion 33b is provided so as to connect the upper end of the vertical portion 33a to the four corners of the upper surface portion 32 corresponding to the four corners of the lower surface portion 31, respectively.

[0030] The reinforcing parts 34 are provided to reinforce each portion of the hanging frame 30. The reinforcing parts 34 are provided along the outer surface of the hanging frame 30 formed into a substantially rectangular parallelepiped shape as described above. 2, a plurality of reinforcing portions 34 are provided at intervals along the vertical direction so as to connect the long side of the lower surface portion 31 to the oblique portions 33b and the long side of the upper surface portion 32. For example, as shown in Fig. 3, reinforcing portions 34 are provided so as to connect the upper ends of adjacent vertical portions 33a along the short sides of the lower surface portion 31 and the upper surface portion 32. The reinforcing portions 34 and vertical portions 33a thus arranged are also arranged obliquely with respect to a rectangle formed by the short sides of the lower surface portion 31. As shown in Figure 5, for example, the reinforcing portion 34 is arranged diagonally with respect to a rectangle formed by the short sides of the upper surface portion 32, the inclined portions 33b connected to both ends of the short sides of the upper surface portion 32, and the reinforcing portion 34 connecting the ends of the inclined portions 33b connected to both ends of the short sides of the upper surface portion 32 to the ends opposite to them.

[0031] The hanging frame 30 formed as described above has a rectangular shape in a plan view, as shown in Fig. 4. Hereinafter, the direction along the long side of the rectangular shape of the hanging frame 30 is referred to as the longitudinal direction of the hanging frame 30. The direction along the short side of the rectangular shape of the hanging frame 30 is referred to as the short side direction of the hanging frame 30. In the illustrated example, the longitudinal direction coincides with the first direction D1, and the short side direction coincides with the second direction D2. The longitudinal dimension of the hanging frame 30 (the length of the hanging frame 30 in the first direction D1) is longer than the short side dimension of the hanging frame 30 (the length of the hanging frame 30 in the second direction D2).

[0032] In this embodiment, the longitudinal dimension of the suspension frame 30, i.e., the length of the long side of the lower surface portion 31, is preferably longer than at least the distance between the first suspension piece TP7a and the second suspension piece TP7b in the longitudinal direction of the suspension frame 30. Moreover, the longitudinal dimension of the suspension frame 30 is more preferably longer than the transition piece TP in the longitudinal direction of the suspension frame 30, and is even more preferably longer than the distance between the suspension pieces TP7 of the transition piece TP (the longitudinal distance between the suspension pieces TP7). That is, the longitudinal dimension of the suspension frame 30 is more preferably longer than the dimension of the transition piece TP in the direction from the first leg TP5a to the fourth leg TP5d, as shown in FIG. This allows, for example, the first hook 11 of the first crane 10 and the second hook 21 of the second crane 20 to be positioned farther away from the central axis of the center pipe TP4 of the transition piece TP than when the first crane 10 and the second crane 20 are directly connected to the hanging piece TP7. This allows the first boom 13 of the first crane 10 and the second boom 23 of the second crane 20 to be in a state closer to vertical.

[0033] In this embodiment, the dimension of the short side of the suspension frame 30, that is, the length of the short sides of the lower surface portion 31 and the upper surface portion 32, is preferably shorter than at least the transition piece TP. That is, as shown in FIG. 4, the dimension of the short side of the suspension frame 30 is more preferably shorter than the dimension of the transition piece TP in the direction from the first leg TP5a to the second leg TP5b. Also, the dimension of the short side of the suspension frame 30 is more preferably the same as the distance between the first suspension piece TP7a and the second suspension piece TP7b (the short side distance between the suspension pieces TP7). This makes it easier to attach the plate member B described later when connecting the suspension frame 30 and the suspension piece TP7. Note that, as described later, it is not necessarily necessary to use the plate member B when connecting the suspension frame 30 and the suspension piece TP7, and for example, a wire for slinging or a fiber sling may be used.

[0034] (Second example of hanging frame) FIG. 6 is a plan view showing a second example of the suspension frame 30, and corresponds to FIG. FIG. 7 is a cross-sectional view taken along line VII-VII of FIG. FIG. 8 is a cross-sectional view taken along the line VIII-VIII in FIG. 6 to 8, the suspension frame 30 of the second example includes a frame body 35 and a reinforcing member 36. Note that, in the suspension frame 30 of the second example, a description of matters common to the first example will be omitted.

[0035] The frame body 35 has a rectangular shape in a plan view. The frame body 35 includes two first members 35a and two second members 35b. The two first members 35a each extend in a first direction D1. The two first members 35a are provided at an interval in the second direction D2. The two second members 35b each extend in the second direction D2. The two second members 35b are provided at an interval in the first direction D1.

[0036] In the illustrated example, the cross-sectional shapes of the first member 35a and the second member 35b are both I-shaped (H-shaped when laid on its side). As shown in Fig. 7 and Fig. 8, the first member 35a includes an upper flange 35a1, a lower flange 35a2, and a web 35a3. The second member 35b includes an upper flange 35b1, a lower flange 35b2, and a web 35b3.

[0037] As shown in FIG. 7, the vertical size of the second member 35b is equal to or smaller than the vertical size of the first member 35a. The end of the second member 35b in the second direction D2 is fixed (for example, welded) to the web 35a3 of the first member 35a in a state where it is butted against the web 35a3 of the first member 35a. The upper flange 35b1 of the second member 35b is located lower than the upper flange 35a1 of the first member 35a. The lower flange 35b2 of the second member 35b is located higher than the lower flange 35a2 of the first member 35a. As a result, in this second example, the upper surface of the hanging frame 30 facing the vertically upward direction is formed by the upper flange 35a1 of the first member 35a. The lower surface of the hanging frame 30 facing the vertically downward direction is formed by the lower flange 35a2 of the first member 35a.

[0038] As shown in FIG. 7, in this embodiment, the girder height of the first member 35a increases toward the middle in the first direction D1. The first member 35a is divided into three regions with different girder heights in the first direction D1. The three regions include one middle region Rc and two end regions Re. In the middle region Rc, the girder height of the first member 35a is large regardless of the position in the first direction D1. The girder height in the middle region Rc is the maximum girder height of the first member 35a. The two end regions Re sandwich the middle region Rc in the first direction D1. In each of the two end regions Re, the girder height of the first member 35a increases toward the middle region Rc.

[0039] As described above, the upper surface of the hanging frame 30 is formed by the upper flange 35a1 of the first member 35a, and the lower surface of the hanging frame 30 is formed by the lower flange 35a2 of the first member 35a. Therefore, it can be said that the girder height of the first member 35a is the size of the hanging frame 30 in the vertical direction. In other words, the thickness (girder height, height) of the hanging frame 30 increases as it approaches the middle of the hanging frame 30 in the first direction D1. However, the thickness of the hanging frame 30 may decrease toward the middle of the hanging frame 30 in the first direction D1. The thickness of the hanging frame 30 may vary in the first direction D1. However, the thickness of the hanging frame 30 may be constant in the first direction D1. In the illustrated example, the thickness of the hanging frame 30 is constant in the second direction D2. That is, in the illustrated example, the thickness of the hanging frame 30 is constant regardless of the position in the second direction D2 as long as the position in the first direction D1 is the same.

[0040] In the illustrated example, the lower flange 35a2 of the first member 35a is a flat surface parallel to the horizontal direction over the entire area in the first direction D1. Therefore, the lower surface of the hanging frame 30 is flat. On the other hand, the upper flange 35a1 of the first member 35a has a mixture of flat and inclined surfaces in the first direction D1. The upper flange 35a1 is a flat surface parallel to the horizontal direction in the middle region Rc, and is an inclined surface inclined to the horizontal direction in the end region Re. The upper surface of the hanging frame 30 is convex upward in the vertical direction when viewed along the second direction D2. However, it is not necessary to adopt a configuration in which the upper flange 35a1 is an inclined surface as a configuration for changing the girder height of the first member 35a.

[0041] The reinforcing members 36 reinforce the frame body 35. The reinforcing members 36 are, for example, I-shaped steel, H-shaped steel, T-shaped steel, L-shaped steel, etc. As shown in Fig. 6 to Fig. 8, the reinforcing members 36 include a first reinforcing member 36a, a second reinforcing member 36b, a third reinforcing member 36c, and a fourth reinforcing member 36d.

[0042] 6, the first reinforcing member 36a extends in the second direction D2. The first reinforcing member 36a connects the two first members 35a in the second direction D2. As shown in FIG. 7, the first reinforcing members 36a are provided in one or more sets, two sets in the illustrated example, with two members in each set. The first reinforcing members 36a of the first set and the first reinforcing members 36a of the second set are each located at one of the two boundaries between the middle region Rc and the end region Re in the first direction D1. For example, the first reinforcing members 36a of the first set are provided at one of the two boundaries, and the first reinforcing members 36a of the second set are provided at the other. The first reinforcing members 36a of the first set and the first reinforcing members 36a of the second set are each located at one of both ends of the middle region Rc in the first direction D1.

[0043] As shown in FIG. 8, the two first reinforcing members 36a included in each set are spaced apart in the vertical direction. The second reinforcing members 36b are diagonal members that connect the two first reinforcing members 36a. In this embodiment, the second reinforcing members 36b are provided in a plurality (four each in the illustrated example) corresponding to each of the first reinforcing members 36a of the first set and the first reinforcing members 36a of the second set.

[0044] As shown in FIG. 6, the third reinforcing member 36c connects the first member 35a and the second member 35b. Four third reinforcing members 36c are provided, corresponding to the corners of the rectangular shape formed by the frame body 35 in a plan view. The first end of each of the four third reinforcing members 36c is joined to the first member 35a, and the second end is joined to the second member 35b. In the illustrated example, the first end is joined to the boundary between the middle region Rc and the end region Re of the first member 35a. The second end is joined to the center of the second member 35b in the second direction D2. The third reinforcing member 36c may connect, for example, the web 35a3 of the first member 35a and the web 35b3 of the second member 35b.

[0045] The fourth reinforcing member 36d connects the first member 35a and the first reinforcing member 36a. The fourth reinforcing member 36d corresponds to the corners of the rectangle formed by the first member 35a and the first reinforcing member 36a in a plan view, and four sets of the fourth reinforcing member 36d are provided. Of the first reinforcing members 36a that form a pair, the fourth reinforcing member 36d in each set may be only one corresponding to only one first reinforcing member 36a located on the upper side, only one corresponding to only one first reinforcing member 36a located on the lower side, or two corresponding to only two first reinforcing members 36a located on both the upper and lower sides. The first end of each of the third reinforcing members 36c included in each set is joined to the first member 35a, and the second end is joined to the first reinforcing member 36a.

[0046] (Connection structure between hanging frame and other components) In this embodiment, both the first and second example suspension frames 30 are provided with a first connection portion C1 (first crane connection portion), a second connection portion C2 (second crane connection portion), and a third connection portion 31a (member connection portion), as shown in, for example, Figure 5. For example, the positions of the first connection portion C1, the second connection portion C2, and the third connection portion 31a may be changeable. Furthermore, for example, when a plurality of the first connection portion C1, the second connection portion C2, and the third connection portion 31a are provided in advance, the first connection portion C1, the second connection portion C2, and the third connection portion 31a to be actually used may be selected from the plurality of the first connection portion C1, the second connection portion C2, and the third connection portion 31a.

[0047] The first connection part C1 is connected to the first crane 10. The first connection part C1 is a part that is connected to the first hook 11 of the first crane 10. The first connection part C1 is provided at one end of the longitudinal direction of the hanging frame 30, at both ends of the hanging frame 30 in the lateral direction. That is, two first connection parts C1 are provided in the hanging frame 30. However, the arrangement of the first connection parts C1 is not limited to this form.

[0048] The second connection part C2 is connected to the second crane 20. The second connection part C2 is a part that is connected to the second hook 21 of the second crane 20. The second connection part C2 is provided at both ends of the suspension frame 30 in the short direction, at the other end of the suspension frame 30 in the long direction. That is, two second connection parts C2 are provided in the suspension frame 30. However, the arrangement of the second connection parts C2 is not limited to this form.

[0049] The first connection part C1 and the second connection part C2 have the same configuration. For example, a known shackle is preferably used for the first connection part C1 and the second connection part C2. The first connection part C1 and the second connection part C2 are provided on the upper surface of the suspension frame 30. As shown in Figs. 2 to 5, in the suspension frame 30 of the first example, the first connection part C1 and the second connection part C2 are provided, for example, at the upper end of the vertical part 33a, and as shown in Figs. 6 to 8, in the suspension frame 30 of the second example, they are provided, for example, at the upper ends of both ends in the second direction of the first member 35a.

[0050] As described above, two each of the first connection parts C1 and the second connection parts C2 are provided on the hanging frame 30. Therefore, as shown in Fig. 5, two each of the first hooks 11 and the second hooks 21 connected to the first connection parts C1 and the second connection parts C2, respectively, are also provided. However, the numbers of the first connection parts C1 and the second connection parts C2, and the numbers of the first hooks 11 and the second hooks 21 are not limited to this.

[0051] In this embodiment, the distance between the first connection part C1 and the center of the hanging frame 30 may be different from the distance between the second connection part C2 and the center of the hanging frame 30. That is, for example, the position of the second connection part C2 in the hanging frame 30 may be provided at a position moved from the end of the longitudinal direction of the hanging frame 30 to the longitudinal center side of the hanging frame 30. In this way, for example, when the center of gravity of the transition piece TP is in a position shifted from the central axis of the center pipe TP4, the loads acting on the first crane 10 and the second crane 20 may be made uniform. In addition, for example, when the center of gravity of the transition piece TP is in the center of the hanging frame 30, the loads acting on the first crane 10 and the second crane 20 do not have to be uniform.

[0052] The third connection portion 31a is connected to the transition piece TP. The third connection portion 31a is, for example, a plate-shaped member and has a through hole. The third connection portion 31a is provided on the lower surface of the suspension frame 30. In the suspension frame 30 of the first example, for example, as shown in Figs. 2 to 5, the third connection portion 31a is provided on each long side of the lower surface portion 31, for a total of four, and in the suspension frame 30 of the second example, for example, as shown in Figs. 6 to 8, the third connection portion 31a is provided on each long side of the first member 35a, for a total of four. The four third connection portions 31a are respectively connected to the four suspension pieces TP7. A specific connection structure will be described later.

[0053] In this embodiment, the third connection portion 31a is located between the first connection portion C1 and the second connection portion C2 when viewed along the vertical direction. In other words, the third connection portion 31a is located between the first connection portion C1 and the second connection portion C2 in the first direction D1. For example, as shown in FIG. 6 to FIG. 8, in the hanging frame 30 of the second example, the first connection portion C1, the second connection portion C2, and the third connection portion 31a are all provided on the first member 35a. The first connection portion C1 and the second connection portion C2 are located at both ends of the first member 35a in the first direction D1, respectively. The third connection portion 31a is located in the middle of the first member 35a in the first direction D1. In this embodiment, two third connection portions 31a are provided, and each of the two third connection portions 31a is located at one of the two boundaries between the middle region Rc and the end region Re in the first direction D1. In other words, each of the two third connection portions 31a is located at one of both ends of the middle region Rc in the first direction D1.

[0054] In such a hanging frame 30, the thickness (beam height) corresponding to the third connection portion 31a is thicker (higher, larger) than the thicknesses corresponding to the first connection portion C1 and the second connection portion C2. In other words, the thickness of the portion of the hanging frame 30 where the third connection portion 31a is located is thicker than the thicknesses of the portions of the first connection portion C1 and the second connection portion C2. For example, as shown in FIG. 7, in the hanging frame 30 of the second example, the beam height of the portion of the first member 35a where the third connection portion 31a is located is higher than the beam height of the portions of the first connection portion C1 and the second connection portion C2.

[0055] (Connection structure between suspension frame and transition piece) In this embodiment, the four suspension pieces TP7 provided on the transition piece TP described above are connected to the first crane 10 and the second crane 20 via the suspension frames 30. More specifically, the first suspension piece TP7a, the second suspension piece TP7b, the third suspension piece TP7c, and the fourth suspension piece TP7d are each connected to the first crane 10 and the second crane 20 via the suspension frames 30. Two examples of the connection structure between the hanging frame 30 and the hanging piece TP7 will be described below.

[0056] (First example of the connection structure between the suspension frame and the transition piece) The suspension frame 30 and the transition piece TP are connected via, for example, a plate member B. The plate member B is, for example, a long plate member, and has through holes at both ends. In this embodiment, the plate members B include a first plate member B1, a second plate member B2, a third plate member B3, and a fourth plate member B4. When there is no need to distinguish between these, they will be referred to as plate members B. In this embodiment, the suspension frame 30 and the first suspension piece TP7a are connected via a first plate member B1. The suspension frame 30 and the second suspension piece TP7b are connected via a second plate member B2. The suspension frame 30 and the third suspension piece TP7c are connected via a third plate member B3. The suspension frame 30 and the fourth suspension piece TP7d are connected via a fourth plate member B4. In this embodiment, the hanging frame 30 and the hanging piece TP7 are pin-joined by a pin P. More specifically, the following applies. That is, the first plate member B1 and the first suspension piece TP7a are pin-joined. The first plate member B1 and the third connection portion 31a of the suspension frame 30 are pin-joined. The second plate member B2 and the second suspension piece TP7b are pin-joined. The second plate member B2 and the third connection portion 31a of the suspension frame 30 are pin-joined. The third plate member B3 and the third suspension piece TP7c are pin-joined. The third plate member B3 and the third connection portion 31a of the suspension frame 30 are pin-joined. The fourth plate member B4 and the fourth suspension piece TP7d are pin-joined. The fourth plate member B4 and the third connection portion 31a of the suspension frame 30 are pin-joined.

[0057] (Second example of the connection structure between the suspension frame and the transition piece) FIG. 9 is a diagram showing a second example of the connection structure between the suspension frame 30 and the transition piece TP. The suspension frame 30 and the transition piece TP are connected, for example, via a plate member B and a rope-like body W. The plate member B according to the second example is formed in the same manner as in the first example, and differs only in that it is shorter in length. In the second example, the rope-like body W is connected to the third connection part 31a of the suspension frame 30. For example, a nylon sling, a sling rope, or a sling wire is preferably used for the rope-like body W. That is, the rope-like body W is preferably connected, for example, by being hooked onto the third connection part 31a of the suspension frame 30. The rope-like body W may be connected to the third connection part 31a via a shackle. In this embodiment, the rope-like body W includes a first rope-like body W1, a second rope-like body W2, a third rope-like body W3, and a fourth rope-like body W4. When these are not distinguished from each other, they are referred to as rope-like bodies W. In the second example, the first rope-like body W1, the second rope-like body W2, the third rope-like body W3, and the fourth rope-like body W4 are connected to the first plate member B1, the second plate member B2, the third plate member B3, and the fourth plate member B4, respectively. In this embodiment, the suspension frame 30 and the first suspension piece TP7a are connected via the first plate member B1 and the first rope-like body W1. The suspension frame 30 and the second suspension piece TP7b are connected via the second plate member B2 and the second rope-like body W2. The suspension frame 30 and the third suspension piece TP7c are connected via the third plate member B3 and the third rope-like body W3. The suspension frame 30 and the fourth suspension piece TP7d are connected via the fourth plate member B4 and the fourth rope-like body W4. More specifically, it is as follows. That is, the first plate member B1 and the first suspension piece TP7a are pin-jointed. The first plate member B1 and the third connection portion 31a of the suspension frame 30 are connected via the first rope-like body W1. The second plate member B2 and the second suspension piece TP7b are pin-jointed. The second plate member B2 and the third connection portion 31a of the suspension frame 30 are connected via the second rope-like body W2. The third plate member B3 and the third suspension piece TP7c are pin-jointed. The third plate member B3 and the third connection portion 31a of the suspension frame 30 are connected via the third rope-like body W3. The fourth plate member B4 and the fourth suspension piece TP7d are pin-jointed. The fourth plate member B4 and the third connection portion 31a of the suspension frame 30 are connected via the fourth rope-like body W4. The suspension frame 30 and the transition piece TP may be connected only via the rope-like body W, and may not require the plate member B. In this manner, the plate member B is not essential to the connection structure between the suspension frame 30 and the transition piece TP, and a configuration including a rope-like body W such as a nylon sling (fiber sling), a sling rope, or a sling wire may be adopted as the connection structure.

[0058] (How to hang a hanging system) Next, a hoisting method of the hoisting system 1 according to this embodiment will be described. That is, a method of hoisting the transition piece TP using the first crane 10 and the second crane 20 will be described. In this hoisting method, a method of transporting the transition piece TP from, for example, the yard Y to above the lower jacket J will be described. The hanging method according to this embodiment includes an alignment step, a connection step, and a hanging step.

[0059] The positioning process is a process of connecting the hoisting frame 30 to the transition piece TP. When performing the positioning process, it is preferable that the hoisting frame 30 is in a state of being lifted by, for example, the first crane 10 and the second crane 20. At this time, the transition piece TP is placed not on the lower jacket J but on, for example, the yard Y.

[0060] The connection process is a process of connecting the suspension frame 30 and the transition piece TP by any one of the two examples of the connection structure between the suspension frame 30 and the transition piece TP described above. However, the suspension frame 30 and the transition piece TP may be connected by a structure other than the two examples of the connection structure.

[0061] The hoisting process is a process of hoisting the transition piece TP by the first crane 10 and the second crane 20. That is, in the hoisting process, the hoisting frame 30 connected to the transition piece TP by the connection process is hoisted by the first crane 10 and the second crane 20, thereby hoisting the transition piece TP. Through the above-described steps, the transition piece TP according to this embodiment is hoisted. The hoisted transition piece TP is hoisted, for example, from above the yard Y to above the lower jacket J.

[0062] As described above, according to the mutual hoisting system 1 of this embodiment, the hoisting frame 30 can reduce the working radius of each of the first crane 10 and the second crane 20. By reducing the working radius of each of the first crane 10 and the second crane 20, the booms of the first crane 10 and the second crane 20 can be brought into a state closer to vertical. As a result, it is possible to further enhance the lifting capacity of the first crane 10 and the second crane 20. This makes it possible to mutually hoist even a transition piece TP that is too heavy to be hoisted without the hoisting frame 30 by the first crane 10 and the second crane 20. Here, by providing the hoisting frame 30, the lifting weight of the first crane 10 and the second crane 20 itself increases by the amount of the addition of the hoisting frame 30. However, the increase in the lifting capacity of the first crane 10 and the second crane 20 due to the addition of the hoisting frame 30 exceeds the increase in the weight, so that the weight of the transition piece TP that can be hoisted together by the first crane 10 and the second crane 20 becomes larger overall.

[0063] The length of the hanging frame 30 in the first direction D1 is longer than the length of the hanging frame 30 in the second direction D2. Therefore, for example, the portion of the hanging frame 30 to which the first crane 10 and the second crane 20 are connected can be the end portion in the first direction D1 that is longer than the second direction D2. This makes it possible to more reliably reduce the working radius of each of the first crane 10 and the second crane 20.

[0064] By reducing the working radius of each of the first crane 10 and the second crane 20, for example, the portion of the hoisting frame 30 to which the first crane 10 or the second crane 20 is connected and the portion to which the transition piece TP is connected tend to separate in the first direction D1. Then, a large bending moment tends to occur in the hoisting frame 30. Here, the thickness of the hanging frame 30 increases in the first direction D1 as it approaches the center of the hanging frame 30. Therefore, for example, the second moment of area at the center of the hanging frame 30 can be increased, and the hanging frame 30 can bear a large bending moment at the center.

[0065] By reducing the working radius of each of the first crane 10 and the second crane 20, for example, the portion of the hoisting frame 30 to which the first crane 10 or the second crane 20 is connected and the portion to which the transition piece TP is connected tend to separate in the first direction D1, but often do not tend to separate in the second direction D2. In this case, it is possible to reduce the need to consider the bending moment in the second direction D2. Here, the thickness of the hanging frame 30 is constant in the second direction D2. This simplifies the design, for example, by taking into consideration buckling of the hanging frame 30.

[0066] The lower surface of the hanging frame 30 is flat. This makes it easier to temporarily place the hanging frame 30 at a construction site, for example. However, the lower surface of the hanging frame 30 does not have to be flat, and may be inclined.

[0067] The third connection portion 31a is located between the first connection portion C1 and the second connection portion C2 when viewed in the vertical direction. By devising the arrangement of the third connection portion 31a, the first connection portion C1, and the second connection portion C2 in this manner, it is possible to more reliably reduce the working radius of each of the first crane 10 and the second crane 20.

[0068] The thickness of the suspension frame 30 corresponding to the third connection portion 31a is greater than the thickness of the suspension frame 30 corresponding to each of the first connection portion C1 and the second connection portion C2. This makes it possible to make the thickness of the suspension frame 30 appropriate in accordance with the bending moment generated by the weight of the transition piece TP.

[0069] The position of the first crane 10 is substantially point-symmetrical to the position of the second crane 20 across the transition piece TP. This makes it easier for the respective cranes to demonstrate their lifting capabilities, for example.

[0070] In addition, the transition piece TP is lifted by the first crane 10 and the second crane 20. As a result, for example, when the transition piece TP is heavy, it can be lifted by the first crane 10 and the second crane 20, which have a relatively low lifting capacity for the transition piece TP. This makes it unnecessary to prepare a large crane with sufficient lifting capacity for the heavy transition piece TP. This makes it possible, for example, to prevent the large crane from taking up too much space at the construction site.

[0071] Further, the transition piece TP is provided with a first suspension piece TP7a and a second suspension piece TP7b. The first suspension piece TP7a and the second suspension piece TP7b are connected to the first crane 10 and the second crane 20. This allows each of the first crane 10 and the second crane 20 to be more reliably engaged with the transition piece TP. Also, it is possible to facilitate stable mutual suspension of the transition piece TP. The first hanging piece TP7a is provided between the first leg TP5a and the pipe axis of the center pipe TP4 included in the transition piece TP. The second hanging piece TP7b is provided between the second leg TP5b and the pipe axis of the center pipe TP4 included in the transition piece TP. This ensures a sufficient distance between the first hanging piece TP7a and the second hanging piece TP7b. This reduces the effect of the difference in height at which the first hanging piece TP7a and the second hanging piece TP7b are lifted by the first crane 10 and the second crane 20, making it easier to keep the transition piece TP horizontal.

[0072] Moreover, the transition piece TP is provided with at least four or more suspension pieces TP7 including a first suspension piece TP7a and a second suspension piece TP7b. The at least four or more suspension pieces TP7 are connected to the first crane 10 and the second crane 20. In this way, by using four or more suspension pieces TP7, it is possible to easily maintain the balance of the transition piece TP when suspending the transition piece TP together. Therefore, the transition piece TP can be suspended more stably. The number of suspension pieces TP does not have to be four or more, and for example, there may be one or more suspension pieces TP.

[0073] In addition, at least four or more suspension pieces TP7 are provided radially from the center of the transition piece TP. This makes it easier to maintain the balance of the transition piece TP more reliably when suspending the transition piece TP. Therefore, the transition piece TP can be suspended more stably.

[0074] Moreover, the first hanging piece TP7a is inserted through the external work floor and connected to the first crane 10 and the second crane 20. Moreover, the second hanging piece TP7b is inserted through the external work floor and connected to the first crane 10 and the second crane 20. By arranging the first hanging piece TP7a and the second hanging piece TP7b in this manner, it is possible to prevent the external work floor from interfering with the connection work when connecting the first crane 10 and the second crane 20 to the first hanging piece TP7a and the second hanging piece TP7b. This can further improve workability.

[0075] In addition, the first hoisting piece TP7a is connected to the first crane 10 and the second crane 20 via the hoisting frame 30. The second hoisting piece TP7b is connected to the first crane 10 and the second crane 20 via the hoisting frame 30. The hoisting frame 30 reduces the working radius of each of the first crane 10 and the second crane 20. That is, by connecting the first crane 10 and the second crane 20 to the first hoisting piece TP7a and the second hoisting piece TP7b via the hoisting frame, the booms of the first crane 10 and the second crane 20 are brought into a state closer to vertical than when the first crane 10 and the second crane 20 are directly connected to the first hoisting piece TP7a and the second hoisting piece TP7b. This reduces the working radius of each of the first crane 10 and the second crane 20, making it easier for the first crane 10 and the second crane 20 to demonstrate their performance. Therefore, the workability of the first crane 10 and the second crane 20 can be improved.

[0076] Furthermore, the hoisting frame 30 is longer in the longitudinal direction thereof than the distance between the hoisting pieces TP7 of the transition piece TP. This allows the working radius of each of the first crane 10 and the second crane 20 to be further reduced. This further improves the workability of the first crane 10 and the second crane 20.

[0077] The length of the suspension frame 30 may be equal to or less than the distance between the suspension pieces TP7 of the transition piece TP in the short direction of the suspension frame 30. However, the length of the suspension frame 30 does not have to be equal to or less than the distance between the suspension pieces TP7 of the transition piece TP in the short direction of the suspension frame 30. The length of the suspension frame 30 may be the same as the distance between the first suspension piece TP7a and the second suspension piece TP7b in the short direction of the suspension frame 30.

[0078] Here, when connecting the suspension frame 30 to the first suspension piece TP7a or the second suspension piece TP7b, for example, a large-diameter wire that can accommodate the heavy transition piece TP and a shackle that can accommodate the large-diameter wire are required. However, it may take time to procure such a wire and shackle. Therefore, the suspension frame 30 and the first suspension piece TP7a are connected via the first plate member B1. The suspension frame 30 and the second suspension piece TP7b are connected via the second plate member B2. This allows the suspension frame 30 and the first suspension piece TP7a or the second suspension piece TP7b to be connected without using a large diameter wire. Therefore, a general-purpose product can be used for the connection structure between the suspension frame 30 and the first suspension piece TP7a or the second suspension piece TP7b, thereby reducing costs.

[0079] Furthermore, the first plate member B1 and the first hanging piece TP7a are pin-joined. The first plate member B1 and the hanging frame 30 are pin-joined. The second plate member B2 and the second hanging piece TP7b are pin-joined. The second plate member B2 and the hanging frame 30 are pin-joined. This makes it easy to join the above-mentioned components together.

[0080] In addition, the first plate member B1 and the first hanging piece TP7a are pin-jointed. The first plate member B1 and the hanging frame 30 are connected via the first rope-like body W1. The second plate member B2 and the second hanging piece TP7b are pin-jointed. The second plate member B2 and the hanging frame 30 are connected via the second rope-like body W2. This makes it easier to adjust the positions of the respective components by bending the first rope-like body W1 and the second rope-like body W2, for example, when joining and removing the respective components described above. Therefore, the respective components can be easily attached and removed by pin joints. This further improves workability.

[0081] The hoisting frame 30 is provided with a first connection part C1 connected to the first hook 11 of the first crane 10 and a second connection part C2 connected to the second hook 21 of the second crane 20. The distance between the first connection part C1 and the center of the hoisting frame 30 is different from the distance between the second connection part C2 and the center of the hoisting frame 30. This allows the positions of the first crane 10 and the second crane 20 to be appropriately adjusted, for example, to match the center of gravity of the transition piece TP, which is the object of mutual hoisting. Therefore, the transition piece TP can be lifted more stably.

[0082] Moreover, the first crane 10 and the second crane 20 face each other across the pipe axis of the center pipe TP4 of the transition piece TP. By arranging the first crane 10 and the second crane 20 in this manner, it is possible to easily adjust the balance of the loads acting on the first crane 10 and the second crane 20 when hoisting the transition piece TP together. This makes it possible to further stabilize each of the first crane 10 and the second crane 20 during operation.

[0083] Furthermore, according to the hoisting method of this embodiment, the transition piece TP is hoisted by the first crane 10 and the second crane 20 in the hoisting process. As a result, for example, when the weight of the transition piece TP is large, it can be hoisted by the first crane 10 and the second crane 20, which have a relatively low hoisting capacity for the transition piece TP. This makes it unnecessary to prepare a large crane with sufficient hoisting capacity for the heavy transition piece TP. This makes it possible, for example, to prevent the large crane from taking up too much space at the construction site.

[0084] The technical scope of the present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present disclosure.

[0085] In the above embodiment, the case where the hoisting system 1 hoists the transition piece TP has been described, but the object (the lifted member) hoisted by the hoisting system 1 is not limited to the transition piece TP. For example, the hoisting system 1 can hoist piles, jackets, bridge girders, etc. For example, the hoisting system 1 can hoist members constituting an offshore structure.

[0086] The length of the hanging frame 30 in the second direction D2 may be longer than the length of the hanging frame 30 in the first direction D1.

[0087] A hoist consisting of one beam member may be used as the working radius adjustment member instead of the hoist frame 30. In the hoist, the first connection portion C1, the second connection portion C2, and the third connection portion 31a are all provided on the one beam member. As shown in FIG. 4, in the embodiment, the longitudinal direction of the suspension frame 30 extends, in a plan view, along a straight line passing through the central axis of the lower jacket J but not passing through leg TP5 of the lower jacket J. However, when using a hanging balance as described above, the longitudinal direction of the one beam member may extend, in a plan view, along a straight line passing through the central axis of the lower jacket J and passing through the leg TP5 of the lower jacket J. Note that the longitudinal direction of the hanging frame 30 as in the above embodiment may extend, in a plan view, along a straight line passing through the central axis of the lower jacket J and passing through the leg TP5 of the lower jacket J.

[0088] In the above embodiment, the case where the hoisting is performed by two cranes has been described, but the present invention is not limited to this. The hoisting may be performed by three or more cranes, and the hoisting system may include three or more cranes.

[0089] In addition, within the scope of the present disclosure, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described modified examples may be combined as appropriate.

[0090] (Additional Note) The suspension system 1 according to the embodiment can be understood, for example, as follows.

[0091] (Appendix 1) <1> A dual-lifting system according to one embodiment of the present disclosure comprises a first crane, a second crane, and a lifted member that is dual-lifted by the first crane and the second crane, and further comprises an operating radius adjustment member interposed between the first crane, the second crane, and the lifted member, wherein the operating radius adjustment member is capable of reducing the operating radius of each of the first crane and the second crane.

[0092] The working radius adjustment member can reduce the working radius of each of the first crane and the second crane. By reducing the working radius of each of the first crane and the second crane, the booms of the first crane and the second crane can be brought into a state closer to vertical. As a result, the lifting capacity of the first crane and the second crane can be further enhanced. This makes it possible for the first crane and the second crane to jointly hoist even a lifted object that is too heavy to be lifted without the working radius adjustment member. Here, by providing the working radius adjustment member, the lifting weight of the first and second cranes itself increases by the amount of the working radius adjustment member added. However, the increase in the lifting capacity of the first and second cranes due to the addition of the working radius adjustment member exceeds the increase in the weight, so that the weight of the lifted material that can be lifted by the first and second cranes together increases overall.

[0093] <2> the above <1> In the above-mentioned hoisting system, a configuration may be adopted in which the length of the working radius adjustment member in a first direction, which is a direction along the horizontal direction and a straight line connecting the first crane and the second crane, is longer than the length of the working radius adjustment member in a second direction, which is a direction along the horizontal direction and perpendicular to the first direction.

[0094] The length of the working radius adjustment member in the first direction is longer than the length of the working radius adjustment member in the second direction. Therefore, for example, the portion of the working radius adjustment member to which the first crane and the second crane are connected can be the end portion in the first direction that is longer than the second direction. This makes it possible to more reliably reduce the working radius of each of the first crane and the second crane.

[0095] <3> the above <2> In the above-mentioned hoisting system, a configuration may be adopted in which the thickness (beam height) of the working radius adjustment member along the vertical direction increases as it approaches the middle of the working radius adjustment member in the first direction.

[0096] By reducing the working radius of each of the first crane and the second crane, for example, the part of the working radius adjustment member to which the first crane or the second crane is connected and the part to which the lifted member is connected tend to separate in the first direction, which makes it easier for a large bending moment to be generated in the working radius adjustment member. Here, the thickness (beam height) of the working radius adjustment member increases in the first direction as it approaches the center of the working radius adjustment member. Therefore, for example, the second moment of area at the center of the working radius adjustment member can be increased, and the center of the working radius adjustment member can bear a large bending moment.

[0097] <4> the above <2> or <3> In the above-mentioned hoisting system, a configuration may be adopted in which the thickness of the working radius adjustment member along the vertical direction is constant in the second direction.

[0098] By reducing the working radius of each of the first and second cranes, for example, the part of the working radius adjustment member to which the first and second cranes are connected and the part to which the lifted member is connected tend to separate in the first direction, but often do not tend to separate in the second direction. In this case, it is possible to reduce the need to consider bending moment in the second direction. Here, the thickness of the working radius adjustment member is constant in the second direction, which simplifies the design taking into account, for example, buckling of the working radius adjustment member.

[0099] <5> the above <1> from <4> In the hoisting system according to any one of the above aspects, a configuration may be adopted in which the lower surface of the working radius adjustment member facing vertically downward is flat.

[0100] The lower surface of the working radius adjustment member is flat, which makes it easier to temporarily place the working radius adjustment member at a construction site, for example.

[0101] <6> the above <1> from <5> In any one of the above embodiments of the hoisting system, the working radius adjustment member may be provided with a member connection portion connected to the lifted member, a first crane connection portion connected to the first crane, and a second crane connection portion connected to the second crane, and the member connection portion may be located between the first crane connection portion and the second crane connection portion when viewed in the vertical direction.

[0102] The member connection part is located between the first crane connection part and the second crane connection part when viewed in the vertical direction. By devising the arrangement of the member connection part, the first crane connection part, and the second crane connection part in this way, it is possible to more reliably reduce the working radius of each of the first crane and the second crane.

[0103] <7> the above <6> In the hoisting system according to the present invention, a configuration may be adopted in which the thickness of the working radius adjustment member along the vertical direction which corresponds to the member connection portion is thicker than the thickness of the working radius adjustment member along the vertical direction which corresponds to each of the first crane connection portion and the second crane connection portion.

[0104] The thickness of the working radius adjustment member that corresponds to the member connection part is thicker than the thicknesses of the working radius adjustment member that correspond to each of the first crane connection part and the second crane connection part, thereby making it possible to make the thickness of the working radius adjustment member appropriate according to the bending moment generated by the weight of the lifted member.

[0105] <8> the above <1> ~ <7> In any one of the above embodiments of the phase hoisting system, a configuration may be adopted in which the position of the first crane is approximately point-symmetrical to the position of the second crane, with the lifted member in between.

[0106] The position of the first crane is substantially point-symmetrical to the position of the second crane with respect to the workpiece being lifted. This makes it easier to demonstrate the lifting capacity of each crane, for example.

[0107] <9> A working radius adjustment member according to one embodiment of the present disclosure is a working radius adjustment member interposed between a first crane and a second crane and a lifted member, and is characterized in that it is capable of reducing the working radius of each of the first crane and the second crane. <10> the above <9> In the working radius adjustment member related to the above, a configuration may be adopted in which the length of the working radius adjustment member in a first direction, which is a direction along the horizontal direction and along a straight line connecting the first crane and the second crane, is longer than the length of the working radius adjustment member in a second direction, which is a direction along the horizontal direction and perpendicular to the first direction. <11> the above <10> In the working radius adjustment member according to the above, a configuration may be adopted in which a thickness of the working radius adjustment member along the vertical direction is constant in the second direction. <12> the above <10> or <11> In the working radius adjustment member according to the present invention, a configuration may be adopted in which the thickness of the working radius adjustment member along the vertical direction increases as the thickness approaches the middle of the working radius adjustment member in the first direction. <13> the above <9> from <12> In the working radius adjustment member according to any one of the above aspects, a configuration may be adopted in which a lower surface of the working radius adjustment member facing downward in the vertical direction is flat. <14> the above <9> from <13> In any one of the embodiments of the working radius adjustment member, the working radius adjustment member may be provided with a member connection portion connected to the lifted member, a first crane connection portion connected to the first crane, and a second crane connection portion connected to the second crane, and the member connection portion may be located between the first crane connection portion and the second crane connection portion when viewed in the vertical direction. <15> the above <14> In the working radius adjustment member related to the above, a configuration may be adopted in which a thickness of the working radius adjustment member along the vertical direction that corresponds to the member connection portion is thicker than a thickness of the working radius adjustment member along the vertical direction that corresponds to each of the first crane connection portion and the second crane connection portion.

[0108] (Appendix 2) <1> A hoisting system according to one embodiment of the present disclosure is a hoisting system for a jacket-type foundation supporting the tower of an offshore wind turbine, comprising a transition piece, a first crane, and a second crane, and is characterized in that the transition piece is hoisted by the first crane and the second crane.

[0109] The transition piece is lifted by the first crane and the second crane together. As a result, for example, when the transition piece is heavy, it can be lifted by the first crane and the second crane, which have a relatively low lifting capacity for the transition piece. This makes it unnecessary to prepare a large crane with sufficient lifting capacity for the heavy transition piece. This makes it possible, for example, to prevent the large crane from taking up too much space at the construction site.

[0110] <2> the above <1> In the above-mentioned double suspension system, the transition piece may be provided with a first suspension piece and a second suspension piece, the first suspension piece and the second suspension piece being connected to the first crane and the second crane, the transition piece may include a first leg, a second leg and a center pipe, the first suspension piece being provided between the first leg and a pipe axis of the center pipe, and the second suspension piece being provided between the second leg and the pipe axis.

[0111] Further, the transition piece is provided with a first suspension piece and a second suspension piece. The first suspension piece and the second suspension piece are connected to the first crane and the second crane. This allows the first crane and the second crane to be engaged with the transition piece more reliably. Also, it is possible to facilitate stable mutual suspension of the transition piece. Furthermore, the first hanging piece is provided between the first leg and the pipe axis of the center pipe included in the transition piece. The second hanging piece is provided between the second leg and the pipe axis of the center pipe included in the transition piece. This ensures a sufficient distance between the first hanging piece and the second hanging piece. This reduces the effect of the difference in height at which the first hanging piece and the second hanging piece are lifted by the first crane and the second crane, making it easier to keep the transition piece horizontal.

[0112] <3> the above <1> or <2> In the above-mentioned suspension system, the transition piece may be provided with at least four or more suspension pieces including a first suspension piece and a second suspension piece, and the at least four or more suspension pieces may be connected to a first crane and a second crane.

[0113] The transition piece is provided with at least four or more suspension pieces including a first suspension piece and a second suspension piece. The at least four or more suspension pieces are connected to a first crane and a second crane. In this way, by using four or more suspension pieces, it is possible to easily maintain the balance of the transition piece when suspending the transition piece from one another. Therefore, the transition piece can be suspending more stably.

[0114] <4> the above <3> In the above-mentioned suspension system, a configuration may be adopted in which the at least four suspension pieces are arranged radially from the center of the transition piece.

[0115] In addition, at least four or more suspension pieces are provided radially from the center of the transition piece. This makes it easier to maintain the balance of the transition pieces more reliably when suspending the transition pieces together. Therefore, the transition pieces can be suspending more stably.

[0116] <5> the above <1> from <4> In any one of the above embodiments of the hoisting system, the transition piece may be configured to include an external work floor, a first hoisting piece, and a second hoisting piece, the first hoisting piece being inserted through the external work floor and connected to the first crane and the second crane, and the second hoisting piece being inserted through the external work floor and connected to the first crane and the second crane.

[0117] Moreover, the first hanging piece is inserted through the external work floor and connected to the first crane and the second crane. Moreover, the second hanging piece is inserted through the external work floor and connected to the first crane and the second crane. By arranging the first hanging piece and the second hanging piece in this manner, it is possible to prevent the external work floor from interfering with the connection work when connecting the first crane and the second crane to the first hanging piece and the second hanging piece. This can further improve workability.

[0118] <6> the above <1> from <5> In any one of the above embodiments, the phased suspension system may further include a suspension frame, wherein the transition piece is provided with a first suspension piece and a second suspension piece, the first suspension piece is connected to the first crane and the second crane via the suspension frame, and the second suspension piece is connected to the first crane and the second crane via the suspension frame, and the suspension frame reduces the working radius of each of the first crane and the second crane.

[0119] Moreover, the first hoisting piece is connected to the first crane and the second crane via a hoisting frame. The second hoisting piece is connected to the first crane and the second crane via a hoisting frame. The hoisting frame reduces the working radius of each of the first crane and the second crane. That is, by connecting the first crane and the second hoisting piece to the first hoisting piece and the second hoisting piece via a hoisting frame, the booms of the first crane and the second crane are brought into a state closer to vertical than when the first crane and the second crane are directly connected to the first hoisting piece and the second hoisting piece. This reduces the working radius of each of the first crane and the second crane, making it easier for the first crane and the second crane to demonstrate their performance. Therefore, the workability of the first crane and the second crane can be improved.

[0120] <7> the above <6> In the above-mentioned suspension system, a configuration may be adopted in which the suspension frame is longer than the transition piece in the longitudinal direction of the suspension frame.

[0121] In addition, the hoisting frame is longer than the transition piece in the longitudinal direction of the hoisting frame, which allows the working radius of each of the first crane and the second crane to be further reduced, thereby further improving the workability of the first crane and the second crane.

[0122] <8> the above <6> or <7> In the above-mentioned suspension system, a configuration may be adopted in which the suspension frame is shorter than the transition piece in a short side direction of the suspension frame.

[0123] <9> the above <6> or <7> In the above-mentioned suspension system, a configuration may be adopted in which the length of the suspension frame is the same as the distance between the first suspension piece and the second suspension piece in the short direction of the suspension frame.

[0124] <10> the above <6> from <9> In the mutual suspension system relating to any one of the above embodiments, a configuration may be adopted in which the suspension frame and the first suspension piece are connected via a first plate member, and the suspension frame and the second suspension piece are connected via a second plate member.

[0125] Here, when connecting the suspension frame to the first suspension piece or the second suspension piece, for example, a large-diameter wire capable of handling the heavy transition piece and a shackle compatible with the large-diameter wire are required. However, it may take time to procure such a wire and shackle. Therefore, the hanging frame and the first hanging piece are connected via a first plate member. The hanging frame and the second hanging piece are connected via a second plate member. This makes it possible to connect the hanging frame and the first hanging piece or the second hanging piece without using a large diameter wire. Therefore, a general-purpose product can be used for the connection structure between the hanging frame and the first hanging piece or the second hanging piece, thereby reducing costs.

[0126] <11> the above <10> In the relative suspension system according to the present invention, a configuration may be adopted in which the first plate member and the first suspension piece are pin-joined, the first plate member and the suspension frame are pin-joined, the second plate member and the second suspension piece are pin-joined, and the second plate member and the suspension frame are pin-joined.

[0127] Furthermore, the first plate member and the first hanging piece are pin-joined. The first plate member and the hanging frame are pin-joined. The second plate member and the second hanging piece are pin-joined. The second plate member and the hanging frame are pin-joined. This makes it easy to join the above-mentioned components together.

[0128] <12> the above <10> or <11> In the above-mentioned suspension system, a configuration may be adopted in which the first plate member and the first suspension piece are pin-jointed, the first plate member and the suspension frame are connected via a first rope-like body, the second plate member and the second suspension piece are pin-jointed, and the second plate member and the suspension frame are connected via a second rope-like body.

[0129] In addition, the first plate member and the first hanging piece are pin-jointed. The first plate member and the hanging frame are connected via a first rope-like body. The second plate member and the second hanging piece are pin-jointed. The second plate member and the hanging frame are connected via a second rope-like body. This makes it easier to adjust the positions of the respective components by bending the first rope-like body and the second rope-like body when joining and removing the respective components described above. Therefore, the respective components can be easily attached and removed by pin joints. This further improves workability.

[0130] <13> the above <6> from <12> In any one of the above embodiments of the mutual suspension system, the suspension frame may be provided with a first connection portion connected to a first hook of the first crane and a second connection portion connected to a second hook of the second crane, and the distance between the first connection portion and the center of the suspension frame may be different from the distance between the second connection portion and the center of the suspension frame.

[0131] The hoisting frame is provided with a first connection part that is connected to the first hook of the first crane and a second connection part that is connected to the second hook of the second crane. The distance between the first connection part and the center of the hoisting frame is different from the distance between the second connection part and the center of the hoisting frame. This allows the positions of the first crane and the second crane to be appropriately adjusted, for example, to match the center of gravity of the transition piece to be hoisted together. This allows the transition piece to be hoisted more stably.

[0132] <14> the above <1> ~ <13> In the hoisting system according to any one of the above aspects, a configuration may be adopted in which the first crane and the second crane face each other across the pipe axis of the center pipe of the transition piece.

[0133] In addition, the first crane and the second crane face each other across the pipe axis of the center pipe of the transition piece. By arranging the first crane and the second crane in this manner, it is possible to easily adjust the balance of the loads acting on the first crane and the second crane when hoisting the transition piece together. This makes it possible to further stabilize each of the first crane and the second crane during operation.

[0134] <15> A hoisting method according to one embodiment of the present disclosure is a hoisting method for a hoisting system of a jacket-type foundation supporting the tower of an offshore wind turbine, the hoisting system comprising a transition piece, a first crane, and a second crane, and is characterized in that the hoisting method includes a hoisting process of hoisting the transition piece by the first crane and the second crane.

[0135] Furthermore, according to the hoisting method of this embodiment, the transition piece is hoisted by the first crane and the second crane in the hoisting process. As a result, for example, when the weight of the transition piece is large, the transition piece can be hoisted by the first crane and the second crane, which have a relatively low hoisting capacity for the transition piece. This makes it unnecessary to prepare a large crane with sufficient hoisting capacity for the heavy transition piece. This makes it possible to prevent, for example, the large crane from taking up too much space at the construction site. [Explanation of symbols]

[0136] 1 Phase suspension system 10. Crane No. 1 20 No. 2 Crane 30 Suspension frame (working radius adjustment part) 31a Third connection part (member connection part) C1 First connection (first crane connection) C2 2nd connection (2nd crane connection) D1 1st direction D2 2nd direction TP Transition piece (lifted part)

Claims

1. A first crane; A second crane; A lifted member that is lifted by the first crane and the second crane together; A suspension system comprising: A working radius adjustment member interposed between the first crane, the second crane, and the lifted member; Further comprising: The working radius adjustment member is capable of reducing the working radius of each of the first crane and the second crane, The working radius adjustment member includes a reinforcing portion for reinforcing each portion of the working radius adjustment member. A suspension system characterized by the above.

2. The working radius adjustment member is provided with a plurality of member connection parts that are connected to the lifted member, The plurality of member connection portions are arranged on one side and the other side of the horizontal center of the working radius adjustment member.

2. The suspension system according to claim 1 .

3. When the working radius adjustment member is connected to the lifted member, the center of gravity of the lifted member is located between the member connection portion on one side and the member connection portion on the other side when viewed along the horizontal direction.

3. The suspension system according to claim 2.

4. The length of the working radius adjustment member in a first direction, which is a direction along a horizontal direction and a straight line connecting the first crane and the second crane, is longer than the length of the working radius adjustment member in a second direction, which is a direction along the horizontal direction and perpendicular to the first direction; 4. The suspension system according to claim 1, wherein the suspension system is a suspension system for supporting a vehicle.

5. The thickness of the working radius adjustment member along the vertical direction increases toward the middle of the working radius adjustment member in the first direction.

5. The suspension system according to claim 4.

6. The thickness of the working radius adjustment member along the vertical direction is constant in the second direction.

5. The suspension system according to claim 4.

7. The lower surface of the working radius adjustment member facing downward in the vertical direction is flat.

4. The suspension system according to claim 1, wherein the suspension system is a suspension system for supporting a vehicle.

8. The working radius adjustment member is provided with a member connection portion connected to the lifted member, a first crane connection portion connected to the first crane, and a second crane connection portion connected to the second crane, The member connection portion is located between the first crane connection portion and the second crane connection portion when viewed along the vertical direction.

4. The suspension system according to claim 1, wherein the suspension system is a suspension system for supporting a vehicle.

9. The thickness of the working radius adjustment member along the vertical direction and corresponding to the member connection portion is thicker than the thickness of the working radius adjustment member along the vertical direction and corresponding to each of the first crane connection portion and the second crane connection portion.

9. The suspension system according to claim 8.

10. The position of the first crane is substantially point-symmetrical with the position of the second crane across the lifted member.

4. The suspension system according to claim 1, wherein the suspension system is a suspension system for supporting a vehicle.

11. A working radius adjustment member interposed between the first crane, the second crane, and the lifted member, The working radius of each of the first crane and the second crane can be reduced, The working radius adjustment member includes a reinforcing portion for reinforcing each portion of the working radius adjustment member. A working radius adjustment member characterized by:

12. The working radius adjustment member is provided with a plurality of member connection parts that are connected to the lifted member, The plurality of member connection portions are arranged on one side and the other side of the horizontal center of the working radius adjustment member. The working radius adjusting member according to claim 11 .

13. When the working radius adjustment member is connected to the lifted member, the center of gravity of the lifted member is located between the member connection portion on one side and the member connection portion on the other side when viewed along the horizontal direction. The working radius adjusting member according to claim 12 .

14. The length of the working radius adjustment member in a first direction, which is a direction along a horizontal direction and a straight line connecting the first crane and the second crane, is longer than the length of the working radius adjustment member in a second direction, which is a direction along the horizontal direction and perpendicular to the first direction; The working radius adjusting member according to any one of claims 11 to 13.

15. The thickness of the working radius adjustment member along the vertical direction is constant in the second direction. The working radius adjusting member according to claim 14 .

16. The thickness of the working radius adjustment member along the vertical direction increases toward the middle of the working radius adjustment member in the first direction. The working radius adjusting member according to claim 14 .

17. The lower surface of the working radius adjustment member facing downward in the vertical direction is flat. The working radius adjusting member according to any one of claims 11 to 13.

18. The working radius adjustment member is provided with a member connection portion connected to the lifted member, a first crane connection portion connected to the first crane, and a second crane connection portion connected to the second crane, The member connection portion is located between the first crane connection portion and the second crane connection portion when viewed along the vertical direction. The working radius adjusting member according to any one of claims 11 to 13.

19. The thickness of the working radius adjustment member along the vertical direction and corresponding to the member connection portion is thicker than the thickness of the working radius adjustment member along the vertical direction and corresponding to each of the first crane connection portion and the second crane connection portion.

20. The working radius adjustment member according to claim 18.

Images