Stinger and method of installing a stinger

Abstract

To provide a stinger capable of properly controlling the stress of a pipeline during laying, and a method for mounting the stinger.SOLUTION: A stinger (10) for guiding a pipeline (4) includes a first roller 20A and a second roller 20B, wherein the pipeline (4) is supported by the first roller 20A and the second roller 20B, and wherein one of the first roller 20A and the second roller 20B moves upwardly and downwardly with the other.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to stingers and methods of attaching stingers. [Background technology]

[0002] Conventionally, conduits are laid using a laying ship equipped with a stinger. Patent Document 1 discloses that a frame that pivotally supports a roller is movable in an upright direction along a guide. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 50-82815 Summary of the Invention [Problem to be solved by the invention]

[0004] However, Patent Document 1 merely discloses that two frames rotatably support one roller.

[0005] The present disclosure aims to provide a stinger and a method for attaching a stinger that can appropriately control stress in a pipeline during installation. [Means for solving the problem]

[0006] A stinger according to one embodiment of the present disclosure is provided at the stern of a laying vessel and guides a pipeline, and comprises a first roller and a second roller, the pipeline is supported by the first roller and the second roller, and one of the first roller and the second roller moves upward and downward together with the other. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to appropriately control the stress in the pipeline during installation. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic overall view showing a situation in which a pipeline is being laid from the stern of a laying vessel using a stinger according to a first embodiment of the present disclosure. [Figure 2] FIG. 2 is a side view showing a portion of the stinger according to the first embodiment of the present disclosure. [Figure 3] FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2. [Figure 4] FIG. 2 is a side view showing the vicinity of a roller provided in the stinger according to the first embodiment of the present disclosure. [Figure 5] FIG. 10 is a side view showing a stinger according to a second embodiment of the present disclosure. [Figure 6] FIG. 10 is a side view showing a portion of a stinger according to a second embodiment of the present disclosure. [Figure 7] FIG. 10 is a side view showing a portion of a stinger according to a third embodiment of the present disclosure. [Figure 8] 1 is a flowchart illustrating a method for attaching a stinger according to an embodiment of the present disclosure. [Figure 9] 1 is a flowchart illustrating a method for attaching a stinger according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0009] Pipelines are laid on the seabed or the like for the purpose of transporting natural gas, oil, etc. Pipelines are laid on the seabed or the like using a laying ship. For example, a laying ship equipped with a stinger is used to lay the pipeline. In this case, pipes are welded on a welding line on the laying ship to form the pipeline, and the pipeline is laid on the seabed without damaging it. The laying ship moves forward in accordance with the progress of the pipe welding work, and the pipeline is sent out into the sea from a stinger located at the stern of the laying ship. The pipeline sent out into the sea is then settled on the seabed. The pipeline sent out from the stinger into the seabed is bent in an S-shape when it hits the seabed, which generates stress (bending stress) in the pipeline, which may cause it to buckle. Therefore, it is necessary to prevent excessive stress from occurring in the pipeline. In order to prevent excessive stress from occurring in the pipeline, it is necessary to properly control the stress in the pipeline. Furthermore, since stress varies depending on the position along the length of the pipeline, it is necessary to properly control the stress at each position along the length of the pipeline.

[0010] (First embodiment) A Stinger 10 according to a first embodiment of the present disclosure will be described with reference to Figures 1 to 4. In the following description, the longitudinal direction of the Stinger 10 is referred to as the X-axis direction (length direction), the height direction of the Stinger 10 that is perpendicular to the X-axis direction is referred to as the Z-axis direction (up-down direction), and the direction perpendicular to the X-axis and Z-axis directions is referred to as the Y-axis direction (width direction). The stinger 10 is a construction jig used to support a downward force in the Z-axis direction acting on the pipeline 4, and to safely send the pipeline 4 to the seabed, riverbed, lakebed, or the like by suppressing the generation of excessive stress on the pipeline 4. In this embodiment, for example, a case where the pipeline 4 is sent to the seabed 1 will be described. The pipeline 4 is used, for example, to transport oil or gas. FIG. 1 shows a situation in which a pipeline 4 is being laid on the seabed 1 from the stern 3 of a laying ship 2 using a stinger 10 according to this embodiment. The pipeline 4 is formed by welding, for example, 6-m or 11-12-m pipes 5 at a welding line (not shown) on the laying ship 2. Alternatively, the pipeline 4 may be formed by welding two 12-m pipes 5 together to form a 24-m long pipe, known as a double joint. The welding line includes assembly, welding, inspection, coating, and other processes to form the pipeline 4. The formed pipeline 4 is then sent out to the sea surface 6 through the stinger 10, and is laid on the seabed 1 at a water depth of, for example, about 80 m as the laying ship 2 advances. Alternatively, a construction method known as S-Lay involves laying the pipeline 4 on the seabed 1 at a water depth of about 300 mm.

[0011] The stinger 10 is a structure provided at the stern 3 of the laying barge 2 and having a buoyancy structure extending in the longitudinal direction of the laying barge 2. The stinger 10 supports the pipeline 4, thereby serving to prevent excessive stress from occurring in the pipeline 4 and to prevent buckling. The Stinger 10 is a strong framework structure made up of a floating structure extending in the longitudinal direction (X-axis direction) of the Stinger 10. The main framework structure of the Stinger 10 is as follows. The Stinger 10 comprises four main floating structures. Specifically, as shown in FIGS. 2 and 3, the floating structure comprises two upper tubular frame members 11A and 11B arranged along the X-axis direction above the Stinger 10, and two lower tubular frame members 12A and 12B arranged along the X-axis direction below the Stinger 10. Note that FIG. 3 is a cross-sectional view taken along the arrows III-III in FIG. 2, but the cross-sectional view is omitted for convenience. Note that the Stinger 10 includes a mechanism for adjusting the angle of the Stinger 10 by adjusting the injection amount into the tubular frame members of the Stinger 10 so as to balance the sum of the loads acting vertically downward on the Stinger 10 from the pipeline 4 via rollers (described later) with the buoyancy acting on the Stinger 10. Alternatively, the Stinger 10 may include a mechanism for holding the Stinger 10 from the laying ship 2 using a driving device such as a winch.

[0012] The upper tubular frame member 11A and the lower tubular frame member 12A are connected at their ends in the X-axis direction by an upright tubular member 13A along the Z-axis direction. The upper tubular frame member 11B and the lower tubular frame member 12B are connected at their ends in the X-axis direction by an upright tubular member 13B along the Z-axis direction. The lower tubular frame member 12A and the lower tubular frame member 12B are connected by a lower horizontal tubular member 16 along the Y-axis direction. The upper tubular frame member 11A and the lower tubular frame member 12A are connected by inclined tubular members 17A and 18A. In Fig. 2, the inclined tubular member 17A extends from the upper tubular frame member 11A at a slope in a downward right direction to the lower tubular frame member 12A. In Fig. 2, the inclined tubular member 18A extends from the upper tubular frame member 11A at a slope in a downward left direction to the lower tubular frame member 12A. In other words, as shown in Fig. 2, the inclined tubular member 17A and the inclined tubular member 18A are arranged in a truss shape between the upper tubular frame member 11A and the lower tubular frame member 12A. The upper tubular frame member 11B and the lower tubular frame member 12B are connected by inclined tubular members 17B and 18B. In Fig. 2, the inclined tubular member 17B extends from the upper tubular frame member 11B to the lower right and to the lower tubular frame member 12B. In Fig. 2, the inclined tubular member 18B extends from the upper tubular frame member 11B to the lower left and to the lower tubular frame member 12B. In other words, as shown in Fig. 2, the inclined tubular member 17B and the inclined tubular member 18B are arranged in a truss shape between the upper tubular frame member 11B and the lower tubular frame member 12B.

[0013] The longitudinal center portion of the inclined tubular member 17A and the longitudinal center portion of the inclined tubular member 18A are connected by an inclined pipe connecting member 19A along the X-axis direction. The longitudinal center portion of the inclined tubular member 17B and the longitudinal center portion of the inclined tubular member 18B are connected by an inclined pipe connecting member 19B along the X-axis direction.

[0014] These components that make up the stinger 10 (upper tubular frame members 11A, 11B, lower tubular frame members 12A, 12B, upright tubular members 13A, 13B, lower horizontal tubular member 16, inclined tubular members 17A, 17B, 18A, 18B, inclined pipe connecting members 19A, 19B) are tubular components that provide buoyancy.

[0015] One longitudinal end 10A of the stinger 10 is connected to the stern 3 of the laying ship 2. Since the stinger 10 is subject to rocking due to waves, ocean currents, etc., the connecting portion between one end 10A of the stinger 10 and the stern 3 is connected to each other with a pin, for example, so as to prevent the stinger 10 from coming off due to external loads. The other longitudinal end 10B of the stinger 10, which is on the opposite side to one end 10A of the stinger 10, does not need to be fixed, or may be connected, for example, by a wire (not shown) installed on the laying ship 2.

[0016] The pipeline 4, in which the pipes 5 are welded together, is transported from the welding line on the laying barge 2 to the stern 3, and then placed at one end 10A of the stinger 10. The pipeline 4 placed at one end 10A of the stinger 10 is guided into the stinger 10. The pipeline 4 is then transported toward the other end 10B of the stinger 10 by a first roller 20A and a second roller 20B, which will be described later, and is sent out from the other end 10B of the stinger 10 to the seabed 1. At this time, the pipeline 4 is supported by the stinger 10 and transported from the upstream side to the downstream side. The one end 10A side of the stinger 10 is the upstream side, and the other end 10B side is the downstream side.

[0017] The pipes 5 that make up the pipeline 4 are made of, for example, steel pipes with concrete covering their outer surfaces. The pipes 5 have, for example, an outer diameter of 6 inches (152.4 mm) to 60 inches (1524 mm), a thickness of 12.7 mm to 22.2 mm, and a length of 12 m. The outer surface of the pipes 5 does not have to be covered with concrete. The pipe 5 is welded by, for example, shielded metal arc welding, MAG welding, or non-gas welding.

[0018] 2 and 3, the Stinger 10 includes a first roller 20A and a second roller 20B. The second roller 20B is disposed in the width direction of the Stinger 10 relative to the first roller 20A. A set of rollers consisting of the first roller 20A and the second roller 20B may be referred to as roller group G20. The first roller 20A and the second roller 20B are fixed to the upper part of the stinger 10. The pipeline 4 is supported by the first roller 20A and the second roller 20B. The first roller 20A and the second roller 20B are rotatable so as to transport the pipeline 4 from one end 10A (upstream side) to the other end 10B (downstream side) in the longitudinal direction of the stinger 10. This allows the first roller 20A and the second roller 20B to transport the pipeline 4 smoothly. The first roller 20A and the second roller 20B rotate due to the frictional force acting between the pipeline 4 being laid and the surface of each roller (the first roller 20A and the second roller 20B). In this way, the first roller 20A and the second roller 20B rotate automatically as the pipeline 4 flows. The first roller 20A and the second roller 20B support and guide the pipeline 4 from below when viewed along the X-axis direction, and are arranged symmetrically with respect to the pipeline 4.

[0019] It is preferable that the first roller 20A and the second roller 20B are the same roller. The outer diameter, thickness, length in the direction of the rotation axis, etc. of the first roller 20A and the second roller 20B are designed, for example, according to the installation capacity of the laying ship 2. As an example of the size of the first roller 20A and the second roller 20B, the outer diameter is 300 mm to 400 mm, and the length in the direction of the rotation axis is 700 mm to 800 mm.

[0020] When the outer surface of the pipeline 4 is covered with concrete, the first roller 20A and the second roller 20B are made of high-strength steel. The first roller 20A and the second roller 20B may also be covered with a rubber member such as a urethane member.

[0021] One of the first roller 20A and the second roller 20B moves upward and downward together with the other. Both the first roller 20A and the second roller 20B can move up and down simultaneously. When one of the first roller 20A and the second roller 20B moves upward and downward together with the other, the pipeline 4 supported by the first roller 20A and the second roller 20B also moves upward and downward. The stinger 10 includes an adjustment mechanism (not shown) that allows one of the first roller 20A and the second roller 20B to move upward and downward together with the other. The first roller 20A and the second roller 20B move up and down automatically or manually. When the first roller 20A and the second roller 20B are moved up and down automatically, they can be moved up and down by a driving device such as an electric motor, a hydraulic motor, a fluid pressure cylinder, a jack, or a winch. The driving device can also adjust the speed of the up and down movement.

[0022] The first roller 20A and the second roller 20B may be connected in the direction along the Y axis. Specifically, the end of the first roller 20A facing the second roller 20B in the Y axis direction may be connected to the end of the second roller 20B facing the first roller 20A in the Y axis direction. In this case, by connecting a drive device to either the first roller 20A or the second roller 20B, both the first roller 20A and the second roller 20B can be moved up and down.

[0023] When the pipeline 4 is sent out from the stinger 10 into the sea, the pipeline 4 is curved so that it is convex upward on the stinger 10. When the pipeline 4 is curved, excessive stress is generated in the pipeline 4, which may cause the pipeline 4 to buckle. For this reason, it is desirable to adjust the heights of the first roller 20A and the second roller 20B to suppress the curvature of the pipeline 4. The Stinger 10 according to this embodiment is configured such that the first roller 20A and the second roller 20B support the pipeline 4, and one of the first roller 20A and the second roller 20B moves up and down together with the other. With this configuration, the positions of the first roller 20A and the second roller 20B in the Z-axis direction are adjusted to support the pipeline 4 at a location where the curvature of the pipeline 4 is likely to be large, and the first roller 20A and the second roller 20B can be moved up and down together to suppress the generation of excessive stress on the pipeline 4. As a result, the Stinger 10 according to this embodiment makes it possible to appropriately control the stress on the pipeline 4.

[0024] The first roller 20A and the second roller 20B are desirably provided at positions in the longitudinal direction of the stinger 10 where the curvature of the pipeline 4 is likely to be particularly large. The curvature of the pipeline 4 is determined, for example, by the material, outer diameter, thickness, and weight (including the weight of the concrete covering the pipeline 4), water depth, and tension during installation of the pipeline 4. The curvature of the pipeline 4 is particularly large, for example, at the end opposite the traveling direction of the pipeline laying ship 2 (the other end 10B described below). Therefore, it is preferable that the first roller 20A and the second roller 20B are provided at the other end 10B side, opposite to the one end 10A of the Stinger 10 connected to the stern 3, in the longitudinal direction of the Stinger 10. In other words, it is preferable that the first roller 20A and the second roller 20B are provided at the end (other end 10B) side, opposite to the stern 3 side of the laying vessel 2, in the longitudinal direction of the Stinger 10. It is preferable that the first rollers 20A and second rollers 20B are arranged in a balanced manner on the Stinger 10. For example, for a Stinger 10 with a total length of 40 m, the first rollers 20A and second rollers 20B are arranged approximately every 10 m in the X-axis direction.

[0025] According to this embodiment, the first roller 20A and the second roller 20B are provided on the other end 10B side of the stinger 10, which is a position where the curvature of the pipeline 4 is particularly likely to be large. With this configuration, the stress on the pipeline 4 can be controlled more appropriately.

[0026] The Stinger 10 includes a first support member 30 that supports the first roller 20A and the second roller 20B. The first support member 30 is, for example, a straight beam member, as shown in Fig. 3. The first support member 30 is disposed below the first roller 20A and the second roller 20B, and supports the first roller 20A and the second roller 20B from below.

[0027] According to the present embodiment, the first support member 30 supports the first roller 20A and the second roller 20B. With this configuration, for example, the first support member 30 can move upward or downward, thereby more easily and reliably moving the first roller 20A and the second roller 20B up and down.

[0028] Both ends of the first support member 30 are supported by pillar-shaped members 31A and 31B. The pillar-shaped members 31A and 31B are arranged outside the first support member 30 in the Y-axis direction and extend in the vertical direction (Z-axis direction). The first support member 30 is movable in the height direction along the pillar-shaped members 31A and 31B. The lower ends of the columnar members 31A and 31B are fixed to a center connecting member 32. The center connecting member 32 connects the longitudinal center portion of the inclined pipe connecting member 19A and the longitudinal center portion of the inclined pipe connecting member 19B along the Y-axis direction. In addition, the lower ends of the columnar members 31A and 31B may be fixed to the lower horizontal tubular member 16.

[0029] 3, both ends of the first support member 30 are supported by the columnar members 31A and 31B by brackets 33A and 33B arranged on both ends of the first support member 30. The bracket 33A connects the end of the first support member 30 to the columnar member 31A. The bracket 33B connects the end of the first support member 30 to the columnar member 31B. Both ends of the first support member 30 may be supported by the columnar members 31A and 31B by welding (not shown), wire (not shown), or joining with bolts or pins (not shown).

[0030] According to this embodiment, both ends of the first support member 30 are supported by the pillar-shaped members 31A and 31B. With this configuration, the first support member 30 can be moved up and down more reliably by moving the first support member 30 up and down along the pillar-shaped members 31A and 31B.

[0031] The first roller 20A and the second roller 20B move upward and downward by moving the first support member 30 upward and downward. The first support member 30 can be moved up and down automatically or manually. When the first support member 30 is moved up and down automatically, it can be moved up and down by a driving device such as an electric motor, hydraulic motor, fluid pressure cylinder, jack, or winch. In addition, the driving device can adjust the speed of the up and down movement. The winch can pay out and reel in the wire.

[0032] According to this embodiment, the first roller 20A and the second roller 20B are configured to move up and down in accordance with the up and down movement of the first support member 30. With this configuration, the first roller 20A and the second roller 20B can be moved up and down more easily and reliably.

[0033] The first support member 30 includes positioning portions 34A and 34B that position the first support member 30. The positioning portion 34A positions the end portion of the first support member 30 and the columnar member 31A. The positioning portion 34B positions the end portion of the first support member 30 and the columnar member 31B. As the positioning portions 34A, 34B (first positioning portions), for example, pins are used at both ends of the first support member 30. In this case, through holes (not shown) through which the pins pass are provided in the columnar members 31A, 31B. The pins fix the first roller 20A and the second roller 20B to the first support member 30 at a desired height in the Z-axis direction. Furthermore, as positioning portions in the Y-axis direction, for example, guides may be arranged on both ends of the first support member 30.

[0034] According to this embodiment, the first support member 30 is configured to include positioning portions 34A and 34B that position the first support member 30. With this configuration, the positions of the first roller 20A and the second roller 20B can be more reliably determined.

[0035] As described above, the pipeline 4 may be curved on the stinger 10. When the pipeline 4 is curved, the pipeline 4 may not be properly supported by the first roller 20A and the second roller 20B. It is desirable that the first roller 20A and the second roller 20B properly support the pipeline 4 even when the pipeline 4 is curved. The Stinger 10 according to this embodiment includes a hinge 35 connected to the first support member 30. As shown in Fig. 4, the hinge 35 is rotatable around the Y axis, centered on a rotation axis 35-A. This allows the first roller 20A and the second roller 20B to also rotate around the Y axis. The hinges 35 allow the first roller 20A and the second roller 20B to tilt about the Y axis in accordance with the tilt of the pipeline 4 at the positions supported by the first roller 20A and the second roller 20B. In this way, the first roller 20A and the second roller 20B tilt with respect to the longitudinal direction of the stinger 10 via the hinges 35.

[0036] 4 shows a case where the first roller 20A and the second roller 20B are inclined at an angle of θ1 with respect to the longitudinal direction of the stinger 10 due to the inclination of the pipeline 4. In FIG. 4, the first roller 20A and the second roller 20B are inclined at an inclination angle θ1 toward the other end 10B of the stinger 10. The tilt angle θ1 is the angle (°) between the rotation axes of first roller 20A and second roller 20B and a line parallel to the X-axis direction when viewed along the Y-axis direction. In Fig. 4, θ1 denotes the angle between rotation axis 20A-A of first roller 20A and a line parallel to the X-axis direction. As the inclination of the pipeline 4 at the position supported by the first roller 20A and the second roller 20B increases, the inclination angle θ1 of the first roller 20A and the second roller 20B decreases. When the pipeline 4 is not inclined with respect to the longitudinal direction of the stinger 10, the inclination angle θ1 is 90°.

[0037] The Stinger 10 may be provided with roller support portions 36A and 36B that support the first roller 20A and the second roller 20B. The roller support portion 36A supports the first roller 20A. The roller support portion 36B supports the second roller 20B. The roller support portions 36A and 36B may be an integrated roller support portion 36. Roller support portion 36A supports both ends of the rotation shaft of first roller 20A. Roller support portion 36B supports both ends of the rotation shaft of second roller 20B. When roller support portion 36A and roller support portion 36B are integrated into roller support portion 36, roller support portion 36 supports both ends of the rotation shaft of first roller 20A and both ends of the rotation shaft of second roller 20B.

[0038] 4, the hinge 35 may connect the roller support portions 36, 36A, 36B to the first support member 30. This allows the first roller 20A and the second roller 20B to tilt relative to the longitudinal direction of the Stinger 10 via the hinge 35.

[0039] According to this embodiment, the first roller 20A and the second roller 20B are configured to incline with respect to the longitudinal direction of the stinger 10 via the hinge 35. With this configuration, the first roller 20A and the second roller 20B incline from the hinge 35 as a starting point so as to follow the curvature and tension of the pipeline 4 at the positions where they are supported by the first roller 20A and the second roller 20B. This allows the pipeline 4 to be supported more appropriately.

[0040] The inclination angle θ1 of the first roller 20A and the second roller 20B with respect to the longitudinal direction of the stinger 10 is, for example, 60° to 90° toward the other end 10B of the stinger 10. In addition, the first roller 20A and the second roller 20B may be inclined toward the one end 10A side of the stinger 10.

[0041] The first roller 20A and the second roller 20B at least partially overlap when viewed in a direction parallel to the width direction of the Stinger 10 (the horizontal direction and perpendicular to the longitudinal direction of the Stinger 10). The first roller 20A and the second roller 20B may completely overlap when viewed in a direction parallel to the width direction of the Stinger 10. When the first roller 20A and the second roller 20B completely overlap when viewed in a direction parallel to the width direction of the Stinger 10, the rotation axis of the first roller 20A and the rotation axis of the second roller 20B are positioned on a straight line extending in the Y-axis direction when viewed in a direction parallel to the Z-axis direction (height direction).

[0042] According to this embodiment, the first roller 20A and the second roller 20B are configured to at least partially overlap when viewed in a direction parallel to the width direction of the stinger 10. With this configuration, the pipeline 4 can be guided more reliably.

[0043] The first roller 20A and the second roller 20B are preferably arranged in a V-shape when viewed along the longitudinal direction of the Stinger 10. As shown in FIG. 3, the first roller 20A and the second roller 20B are arranged in a V-shape that is convex downward when viewed along the longitudinal direction of the Stinger 10. The angle θ2 (°) formed between the first roller 20A and the second roller 20B when viewed along the longitudinal direction of the Stinger 10 can be determined, for example, taking into account the outer diameters of the first roller 20A and the second roller 20B, and is also determined to be versatile enough to accommodate various outer diameters of the pipeline 4. The angle θ2 is the angle formed between the rotation axis of the first roller 20A and the rotation axis of the second roller 20B when viewed along the longitudinal direction of the Stinger 10.

[0044] According to this embodiment, the first roller 20A and the second roller 20B are configured to be arranged in a V-shape when viewed along the longitudinal direction of the stinger 10. With this configuration, the pipeline 4 can be guided more reliably.

[0045] The angle θ2 formed by the first roller 20A and the second roller 20B is preferably 110° to 130°, which allows the pipeline 4 to be guided more reliably.

[0046] When the first roller 20A and the second roller 20B are arranged in a V-shape when viewed along the longitudinal direction of the Stinger 10, the first support member 30 may also have a V-shape in accordance with the V-shape formed by the first roller 20A and the second roller 20B. That is, the first support member 30 may be formed in a V-shape when viewed along the longitudinal direction of the Stinger 10. In this case, the first support member 30 may have a V-shape that forms the same angle as the angle θ2 formed between the first roller 20A and the second roller 20B.

[0047] The first roller 20A and the second roller 20B do not have to be arranged in a V-shape when viewed along the longitudinal direction of the Stinger 10. For example, the first roller 20A and the second roller 20B may be arranged so that the angle θ2 formed between the first roller 20A and the second roller 20B is 180°.

[0048] The pipeline 4 may be sandwiched between the first roller 20A and the second roller 20B. With this configuration, the pipeline 4 can be guided more reliably.

[0049] (Second embodiment) A Stinger 100 according to a second embodiment of the present disclosure will be described with reference to Figures 5 and 6. The same components as those in the first embodiment will be assigned the same reference numerals, and a description thereof will be omitted, with differences being mainly described. In the first embodiment, as shown in Fig. 2, a set of first rollers 20A and second rollers 20B is arranged. That is, a set of roller group G20 made up of the first rollers 20A and the second rollers 20B is arranged. In the second embodiment, a plurality of sets of first rollers 20A and second rollers 20B are arranged along the longitudinal direction (X-axis direction) of the Stinger 100.

[0050] In the example shown in FIGS. 5 and 6, two pairs of first rollers 20A and second rollers 20B are arranged along the longitudinal direction of the stinger 100. Specifically, the stinger 100 includes a first roller 20A-1, a second roller 20B-1, a third roller 20A-2, and a fourth roller 20B-2. The second roller 20B-1 is disposed in the width direction of the stinger 100 relative to the first roller 20A-1. The third roller 20A-2 is disposed in the longitudinal direction of the stinger 100 relative to the first roller 20A-1. The fourth roller 20B-2 is disposed in the width direction of the stinger 100 relative to the third roller 20A-2. In this embodiment, a pair of roller groups (first roller group G20-1) consisting of a first roller 20A-1 and a second roller 20B-1, and a pair of roller groups (second roller group G20-2) consisting of a third roller 20A-2 and a fourth roller 20B-2 are arranged along the longitudinal direction of the Stinger 100.

[0051] The stinger 100 comprises a first support member 30-1 and a second support member 30-2. The first support member 30-1 supports the first roller 20A-1 and the second roller 20B-1, that is, the first support member 30-1 supports the first roller group G20-1. The second support member 30-2 supports the third roller 20A-2 and the fourth roller 20B-2, that is, the second support member 30-2 supports the second roller group G20-2. The pipeline 4 is supported by the first roller 20A-1 and the second roller 20B-1, and the third roller 20A-2 and the fourth roller 20B-2. That is, the pipeline 4 is supported by the first roller group G20-1 and the second roller group G20-2.

[0052] One of the first roller 20A-1 and the second roller 20B-1 moves upward and downward together with the other by moving the first support member 30-1 upward and downward. One of the third roller 20A-2 and the fourth roller 20B-2 moves upward and downward together with the other by moving the second support member 30-2 upward and downward.

[0053] The curvature and tension of the pipeline 4 differ depending on the position in the longitudinal direction of the stinger 100. Therefore, it is desirable to adjust the heights of the first roller 20A-1 and the second roller 20B-1 at each position in accordance with the curvature and tension at each position in the longitudinal direction of the pipeline 4. The Stinger 100 of this embodiment is configured such that a first roller group G20-1 consisting of a first roller 20A-1 and a second roller 20B-1, and a second roller group G20-2 consisting of a third roller 20A-2 and a fourth roller 20B-2 are arranged along the longitudinal direction of the Stinger 100, and each roller group (G20-1, G20-2) moves up and down. That is, the pipeline 4 is supported by the first roller 20A-1 and the second roller 20B-1, and the third roller 20A-2 and the fourth roller 20B-2. One of the first roller 20A-1 and the second roller 20B-1 moves upward and downward together with the other roller by moving the first support member 30-1 upward and downward. One of the third roller 20A-2 and the fourth roller 20B-2 moves upward and downward together with the other roller by moving the second support member 30-2 upward and downward. As a result, the pipeline 4 is supported at two points in the longitudinal direction of the Stinger 100, so the pipeline 4 can be supported at an appropriate height at each position in the longitudinal direction of the Stinger 100. As a result, according to this embodiment, it is possible to appropriately control the stress in the pipeline 4 and reliably guide the pipeline 4. Also in this embodiment, the Stinger 100 has a hinge 35 connected to the first support member 30-1 and a hinge 35 connected to the second support member 30-2, and the first roller group G20-1 (first roller 20A-1 and second roller 20B-1) and the second roller group G20-2 (third roller 20A-2 and fourth roller 20B-2) may be configured to be inclined with respect to the longitudinal direction of the Stinger 100 via the hinge 35.

[0054] The first roller group G20-1 (first roller 20A-1 and second roller 20B-1) and the second roller group G20-2 (third roller 20A-2 and fourth roller 20B-2) may be disposed, for example, at one end 10A side and the other end 10B side of the Stinger 100, respectively. For example, one set of first roller groups G20-1 may be disposed at one end 10A side of the Stinger 100, and one set of second roller groups G20-2 may be disposed at the other end 10B side of the Stinger 100. Note that it is preferable that the first roller groups G20-1 and the second roller groups 20-2 are disposed in a balanced manner in the Stinger 100. For example, for a Stinger 100 with a total length of 40 m, the first roller groups 20-1 and the second roller groups 20-2 are disposed approximately every 10 m in the X-axis direction.

[0055] Note that three or more pairs of roller groups G20 may be provided along the X-axis direction. That is, three or more pairs of first roller groups G20-1 each consisting of a first roller 20A-1 and a second roller 20B-1 may be provided along the X-axis direction. With this configuration, the roller group G20 can be arranged at an appropriate position according to the curvature and tension of the pipeline 4 at each position in the longitudinal direction of the Stinger 100. This makes it possible to more appropriately control the stress on the pipeline 4 and more reliably guide the pipeline 4.

[0056] When three or more pairs of roller groups G20 are provided along the X-axis direction, these pairs of roller groups G20 do not have to be arranged at equal intervals along the X-axis direction. For example, the roller groups may be concentrated on one end 10A side and the other end 10B side of the Stinger 100. For example, one set of first roller groups G20-1 may be arranged on one end 10A side of the Stinger 100, and two sets of second roller groups G20-2 may be arranged on the other end 10B side of the Stinger 100. Alternatively, the roller groups G20 may be arranged at equal intervals along the X-axis direction. The number of pairs of roller groups G20 arranged along the X-axis direction is not limited. The number of pairs of roller groups G20 is determined taking into consideration, for example, the water depth, the outer diameter (weight) of the pipeline 4, and the tension. For example, as the water depth increases, the weight of the pipeline 4 increases, and therefore the weight supporting the pipeline 4 also increases. This requires more fulcrums to support the pipeline 4, and the number of pairs of roller groups G20 increases.

[0057] When a plurality of pairs of roller groups G20 are provided along the X-axis direction, the roller outer diameters of the respective roller groups G20 (the outer diameter of the first roller 20A-1 and the outer diameter of the second roller 20B-1) may be the same. In this embodiment, the roller outer diameters of the first roller group G20-1 (the outer diameter of the first roller 20A-1 and the outer diameter of the second roller 20B-1) are the same as the roller outer diameters of the second roller group G20-2 (the outer diameter of the first roller 20A-1 and the outer diameter of the second roller 20B-1). Alternatively, for example, taking into consideration the length of the stinger 100, the outer diameter, length, and weight of the pipeline 4, the outer diameters of the first roller 20A-1 and the second roller 20B-1 that make up each roller group G20 may be made different.

[0058] When a plurality of pairs of roller groups G20 are provided along the X-axis direction, the inclination angle θ1 of the first roller 20A-1 and the second roller 20B-1 at each position in the longitudinal direction of the Stinger 100 may differ depending on the inclination angle of the pipeline 4 at each position. For example, when the curvature at the other end 10B of the Stinger 100 is greater than the curvature and tension at one end 10A of the Stinger 100, the inclination angle θ1 of the first roller 20A-1 and the second roller 20B-1 at the other end 10B of the Stinger 100 will be smaller than the inclination angle θ1 of the first roller 20A-1 and the second roller 20B-1 at one end 10A of the Stinger 100.

[0059] When multiple pairs of roller groups G20-1 are arranged along the X-axis direction, the angle θ2 formed between the first roller 20A-1 and the second roller 20B-1 at each position along the longitudinal direction of the Stinger 100 may be different or the same.

[0060] (Third embodiment) A Stinger 200 according to a third embodiment of the present disclosure will be described with reference to Fig. 7. The same components as those in the first and second embodiments will be assigned the same reference numerals, and a description thereof will be omitted, with differences being mainly described. In the second embodiment, as shown in Fig. 6, a first support member 30-1 supports a first roller group G20-1, and a second support member 30-2 supports a second roller group G20-2. In the third embodiment, as shown in Fig. 7, one support member 30-3 (third support member) supports the first roller group G20-1 and the second roller group G20-2.

[0061] The stinger 200 includes a first roller 20A-1, a second roller 20B-1, a third roller 20A-2, a fourth roller 20B-2, and a support member 30-3. The second roller 20B-1 is disposed in the width direction of the stinger 200 relative to the first roller 20A-1. The third roller 20A-2 is disposed in the longitudinal direction of the stinger 200 relative to the first roller 20A-1. The fourth roller 20B-2 is disposed in the width direction of the stinger 200 relative to the third roller 20A-2. The support member 30-3 supports the first roller 20A-1 and the second roller 20B-1, and the third roller 20A-2 and the fourth roller 20B-2. That is, the support member 30-3 supports a first roller group G20-1 consisting of the first roller 20A-1 and the second roller 20B-1, and a second roller group G20-2 consisting of the third roller 20A-2 and the fourth roller 20B-2. The pipeline 4 is supported by the first roller 20A-1, the second roller 20B-1, the third roller 20A-2 and the fourth roller 20B-2.

[0062] The first roller 20A-1, the second roller 20B-1, the third roller 20A-2, and the fourth roller 20B-2 all move upward and downward by moving the support member 30-3 upward and downward.

[0063] In the Stinger 200 according to this embodiment, one support member 30-3 supports a first roller group G20-1 consisting of a first roller 20A-1 and a second roller 20B-1, and a second roller group G20-2 consisting of a third roller 20A-2 and a fourth roller 20B-2. The Stinger 200 supports the pipeline 4 with four rollers (the first roller 20A-1, the second roller 20B-1, the third roller 20A-2, and the fourth roller 20B-2). This configuration increases the contact area with the pipeline 4 compared to when the pipeline 4 is supported with two rollers (the first roller 20A-1 and the second roller 20B-1), thereby enabling the pipeline 4 to be supported more reliably. Furthermore, by moving the common support member 30-3 upward and downward, the first roller 20A-1, the second roller 20B-1, the third roller 20A-2, and the fourth roller 20B-2 all move upward and downward. Therefore, even if, for example, one of the four rollers is unable to operate due to a malfunction or the like, the other operable rollers can support the pipeline 4. Also in this embodiment, the Stinger 200 may be provided with a hinge 35 connected to the third support member 30-3, and the roller unit U20 (first roller group G20-1 (first roller 20A-1 and second roller 20B-1) and second roller group G20-2 (third roller 20A-2 and fourth roller 20B-2)) may be configured to incline with respect to the longitudinal direction of the Stinger 200 via the hinge 35. Note that the hinge 35 may be provided individually for each of the multiple roller groups (one for each roller group), or one hinge 35 may be provided collectively for the multiple roller groups.

[0064] A plurality of roller units U20 (first roller group G20-1 and second roller group G20-2), each consisting of four rollers (first roller 20A-1, second roller 20B-1, third roller 20A-2, and fourth roller 20B-2), may be provided along the X-axis direction. For example, two sets of roller units U20 may be provided along the X-axis direction. In this case, for example, roller units U20 may be disposed on one end 10A side and the other end 10B side of the Stinger 100, respectively.

[0065] Three or more roller units U20 may be provided along the X-axis direction. With this configuration, the roller units U20 can be arranged at appropriate positions depending on the stress on the pipeline 4 at each position in the longitudinal direction of the Stinger 100. This makes it possible to more appropriately control the stress on the pipeline 4 and more reliably guide the pipeline 4. For example, the roller units U20 may or may not be arranged at equal intervals along the X-axis direction. For example, one set of roller units U20 may be arranged on one end 10A side of the Stinger 100, and two sets of roller units U20 may be arranged on the other end 10B side of the Stinger 100. The roller units U20 arranged along the X-axis direction are not limited. The number of pairs of roller units U20 is determined, for example, taking into consideration the water depth, the outer diameter (weight) of the pipeline 4, and the tension. For example, as the water depth increases, the weight of the pipeline 4 increases, and the weight supporting the pipeline 4 also increases. This requires more fulcrums to support the pipeline 4, and the number of roller units U20 increases.

[0066] (How to install the Stinger) The following describes a method for attaching the above-described Stingers 10, 100, and 200. The method for attaching the Stingers 10, 100, and 200 according to the above-described embodiments includes a moving step S1 and an attaching step S2.

[0067] The moving step S1 is a step in which one of the first rollers 20A, 20A-1 and the second rollers 20B, 20B-1 is moved upward and downward together with the other in accordance with the stress of the pipeline 4. The installation step S2 is a step of installing the stingers 10, 100, 200 to the stern 3. Either the moving step S1 or the mounting step S2 may be performed first.

[0068] According to the installation method of the stingers 10, 100, 200 of this embodiment, the first rollers 20A, 20A-1 and the second rollers 20B, 20B-1 can be moved up and down depending on the curvature or tension of the pipeline 4 so as to suppress the generation of excessive stress on the pipeline 4. According to this installation method, the stress on the pipeline 4 can be appropriately controlled. When installing the rollers (first rollers 20A, 20A-1 and second rollers 20B, 20B-1) on the stinger (10, 100, 200), the roller support members (30, 30-1, 30-2, 30-3) held at a predetermined height (by a crane, etc.) can be fixed to the main body of the stinger (10, 100, 200) directly or via brackets (33A, 33B) by welding, etc.; that is, installation and vertical positioning can be performed simultaneously.

[0069] 8, the attaching step S2 may be performed after the moving step S1. For example, if the moved first rollers 20A, 20A-1 and second rollers 20B, 20B-1 are positioned in the vertical direction by welding or the like before being installed on the stinger 10, 100, 200, the stinger 10, 100, 200 including the first rollers 20A, 20A-1 and second rollers 20B, 20B-1 can be efficiently attached to the pipeline laying ship 2. In this case, the stress in the pipeline 4 can be simulated in advance, for example, and the moving step S1 may be performed based on the results of the simulation.

[0070] 9, the attachment step S2 may be performed before the moving step S1. In this case, the first rollers 20A, 20A-1 and the second rollers 20B, 20B-1 can be moved and positioned while the stingers 10, 100, 200 are attached to the laying ship 2. This allows for more appropriate control of stress in the pipeline 4.

[0071] 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. For example, the first roller 20A and the second roller 20B may be provided on the one end 10A side of the stinger that is connected to the stern 3 in the longitudinal direction of the stinger 10. In the above-described embodiment, the first support member 30 is provided with a hinge 35. However, as long as the first roller 20A and the second roller 20B are configured to be rotatable around the Y axis, the hinge 35 is not the only option. For example, the first support member 30 and the roller support portion 36 supporting the first roller 20A and the second roller 20B may be joined by a pin. Specifically, the first support member 30 and the roller support portion 36 may be provided with protrusions having through holes penetrating in the Y axis direction, and a pin may be inserted through the through holes of the first support member 30 and the roller support portion 36. With this configuration, the first roller 20A and the second roller 20B may be tilted relative to the longitudinal direction of the Stinger 10, starting from the pin. Furthermore, the first roller 20A and the second roller 20B do not need to be tilted relative to the longitudinal direction of the Stinger 10 via the hinge 35. Furthermore, in the above-described embodiment, one stinger 10 is provided on the laying ship 2, but a plurality of stingers 10 may be connected in series along the longitudinal direction of the stingers 10. The first roller 20A and the second roller 20B do not have to be provided at the other end in the longitudinal direction of the Stinger 10. For example, the first roller 20A and the second roller 20B may be provided at one end 10A of the Stinger 10 that is connected to the stern 3 in the longitudinal direction of the Stinger 10. Furthermore, they may be arranged in the middle of the Stinger 10 in the longitudinal direction. The positioning portions 34A and 34B may not be present, the columnar members 31A and 31B may not be present, and the first support member 30 may not be present. The first roller 20A and the second roller 20B may not overlap at all when viewed in a direction parallel to the width direction of the stinger 10. The first roller 20A and the second roller 20B do not have to be arranged in a V-shape when viewed along the longitudinal direction of the Stinger 10. For example, the first roller 20A and the second roller 20B may be arranged in the same straight line when viewed along the longitudinal direction of the Stinger 10. The pipeline 4 does not have to be sandwiched between the first roller 20A and the second roller 20B, and may, for example, simply pass over the first roller 20A and the second roller 20B. The stinger 10 may be provided at an incline with respect to the sea surface 6. The angle of the stinger 10 with respect to the sea surface 6 can be corrected by adjusting the buoyancy of the stinger 10 or by adjusting the wire that suspends the stinger 10.

[0072] Furthermore, 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.

[0073] (Addendum) The embodiment can be understood, for example, as follows.

[0074] <1> A stinger according to one embodiment of the present disclosure is a stinger that is installed at the stern of a laying vessel and guides a pipeline, and is characterized in that it comprises a first roller and a second roller, the pipeline is supported by the first roller and the second roller, and one of the first roller and the second roller moves upward and downward together with the other.

[0075] One of the first roller and the second roller moves upward and downward together with the other, so that the first roller and the second roller can move up and down together to prevent excessive stress from occurring in the pipeline, thereby making it possible to appropriately control stress in the pipeline.

[0076] <2> the above <1> In the stinger according to the above, the first roller and the second roller may be provided at the other end of the stinger opposite to the one end of the stinger connected to the stern in the longitudinal direction of the stinger.

[0077] In particular, by providing the first roller and the second roller on the other end side of the pipeline where the curvature of the pipeline is likely to be large, the stress in the pipeline can be controlled more appropriately.

[0078] <3> the above <1> or <2> The stinger according to the above aspect may be configured to include a first support member that supports the first roller and the second roller.

[0079] Since the first support member supports the first roller and the second roller, the first roller and the second roller can be moved up and down more easily and reliably, for example, by moving the first support member upward or downward.

[0080] <4> the above <3> In the stinger according to the above, both ends of the first support member may be supported by pillar-shaped members that are arranged outside the first support member and extend in the vertical direction.

[0081] Both ends of the first support member are supported by the pillar-shaped members, so that by moving the first support member up and down along the pillar-shaped members, the first support member can be moved up and down more reliably.

[0082] <5> the above <3> or <4> In the stinger according to the above, a configuration may be adopted in which the first roller and the second roller move upward and downward by moving the first support member upward and downward.

[0083] By moving the first support member in the vertical direction, the first roller and the second roller also move in the vertical direction, so that the first roller and the second roller can be moved up and down more easily and reliably.

[0084] <6> the above <3> from <5> In the Stinger according to any one of the above aspects, the first support member may be provided with a positioning portion that positions the first support member.

[0085] The positioning portion that positions the first support member makes it possible to more reliably position the first roller and the second roller.

[0086] <7> the above <3> from <6> The stinger according to any one of the above aspects may be configured to include a hinge connected to the first support member, and the first roller and the second roller may be inclined relative to the longitudinal direction of the stinger via the hinge.

[0087] The first and second rollers are inclined relative to the longitudinal direction of the stinger via the hinge, so that the first and second rollers are inclined from the hinge as a starting point to follow the curvature and tension of the pipeline at the positions supported by the first and second rollers, thereby providing better support for the pipeline.

[0088] <8> the above <1> from <7> In the stinger according to any one of the above aspects, the first roller and the second roller may be configured to at least partially overlap when viewed in a direction parallel to the width direction of the stinger.

[0089] When viewed in a direction parallel to the width direction of the stinger, the first roller and the second roller at least partially overlap each other, thereby enabling more reliable guidance of the pipeline.

[0090] <9> the above <1> from <8> In the stinger according to any one of the above aspects, the first roller and the second roller may be arranged in a V-shape when viewed along the longitudinal direction of the stinger.

[0091] The first roller and the second roller are arranged in a V-shape when viewed along the longitudinal direction of the stinger, thereby enabling the pipeline to be guided more reliably.

[0092] <10> the above <1> from <9> In the stinger according to any one of the above aspects, a configuration may be adopted in which the pipeline is sandwiched between the first roller and the second roller.

[0093] By sandwiching the pipeline between the first roller and the second roller, the pipeline can be guided more reliably.

[0094] <11> A stinger according to one embodiment of the present disclosure is a stinger that is provided at the stern of a ship and guides a pipeline, and is equipped with a first roller, a second roller, a third roller, a fourth roller, a first support member that supports the first roller and the second roller, and a second support member that supports the third roller and the fourth roller, and the pipeline is supported by the first roller and the second roller and the third roller and the fourth roller, and one of the first roller and the second roller moves upward and downward together with the other by moving the first support member upward and downward, and one of the third roller and the fourth roller moves upward and downward together with the other by moving the second support member upward and downward.

[0095] The pipeline is supported by first and second rollers and third and fourth rollers, and one of the first and second rollers moves upward and downward together with the other by moving the first support member upward and downward, and one of the third and fourth rollers moves upward and downward together with the other by moving the second support member upward and downward. As a result, the pipeline is supported at two points in the longitudinal direction of the stinger, so the pipeline can be supported at an appropriate height at each position in the longitudinal direction of the stinger. This makes it possible to appropriately control the stress in the pipeline and reliably guide the pipeline.

[0096] <12> A stinger according to one embodiment of the present disclosure is a stinger that is installed at the stern of a ship and guides a pipeline, and is characterized in that it comprises a first roller, a second roller, a third roller, a fourth roller, and a support member that supports the first roller, the second roller, and the third roller and the fourth roller, and the pipeline is supported by the first roller, the second roller, the third roller, and the fourth roller, and the first roller, the second roller, the third roller, and the fourth roller all move upward and downward by moving the support member upward and downward.

[0097] The pipeline is supported by the first and second rollers and the third and fourth rollers, and the contact area with the pipeline is increased compared to when the pipeline is supported by two rollers, thereby more reliably supporting the pipeline. Also, by moving the common support member up and down, the first roller, second roller, third roller, and fourth roller all move up and down, so that even if, for example, one of the four rollers is inoperable due to a malfunction or the like, the other operable rollers can support the pipeline.

[0098] <13> A method for attaching a stinger according to one aspect of the present disclosure includes the steps of: <1> from <12> The method for installing a stinger according to any one of the above aspects is characterized by comprising a moving step of moving one of the first roller and the second roller together with the other roller upward and downward in accordance with the stress of the pipeline, and an installation step of installing the stinger to the stern.

[0099] The first roller and the second roller can be moved up and down depending on the curvature or tension of the pipeline so as to prevent excessive stress from occurring in the pipeline, thereby making it possible to appropriately control the stress in the pipeline.

[0100] <14> the above <13> In the stinger mounting method according to the above, the mounting step may be performed after the moving step.

[0101] If the moved first and second rollers are positioned vertically by welding or the like before being installed on the stinger, the stinger equipped with the first and second rollers can be efficiently attached to the laying ship.

[0102] <15> the above <13> In the method for attaching a stinger according to the above aspect, the attaching step may be performed before the moving step.

[0103] With the stinger attached to the laying vessel, the first and second rollers can be moved and positioned, allowing for better control of stress in the pipeline. [Explanation of symbols]

[0104] 2. Tray ship 3 Stern 4. Pipeline 10,100,200 Stinger 10A One end 10B Other end 20A, 20A-1 First roller 20A-2 3rd Roller 20B, 20B-1 Second roller 20B-2 4th Roller 30, 30-1 First support member 30-2 Second support member 30-3 Third support member (support member) 35 Hinge 34A, 34B First positioning part 36, 36A, 36B Roller support part S1 Movement step S2 Installation Steps

Claims

1. A stinger that is provided at the stern of a laying ship and guides a pipeline, A first roller; A second roller; Equipped with the pipeline is supported by the first roller and the second roller; one of the first roller and the second roller moves upward and downward together with the other; A stinger characterized by:

2. the first roller and the second roller are provided at the other end side of the stinger opposite to the one end side of the stinger connected to the stern in the longitudinal direction of the stinger, 2. The stinger of claim 1.

3. a first support member that supports the first roller and the second roller; 2. The stinger of claim 1.

4. Both ends of the first support member are supported by columnar members that are arranged outside the first support member and extend in the vertical direction.

4. The stinger of claim 3.

5. the first roller and the second roller move upward and downward by moving the first support member upward and downward; 4. The stinger of claim 3.

6. The first support member includes a positioning portion that positions the first support member.

6. The stinger of claim 5.

7. a hinge connected to the first support member; the first roller and the second roller are inclined with respect to the longitudinal direction of the stinger via the hinge; 4. The stinger of claim 3.

8. The first roller and the second roller at least partially overlap each other when viewed along a direction parallel to the width direction of the stinger. A stinger according to any one of claims 1 to 7.

9. The first roller and the second roller are arranged in a V-shape when viewed along the longitudinal direction of the stinger. A stinger according to any one of claims 1 to 7.

10. The pipeline is sandwiched between the first roller and the second roller. A stinger according to any one of claims 1 to 7.

11. A stinger installed at the stern of a ship and guiding a pipeline, A first roller; A second roller; A third roller; A fourth roller; a first support member that supports the first roller and the second roller; a second support member that supports the third roller and the fourth roller; Equipped with the pipeline is supported by the first roller and the second roller, and the third roller and the fourth roller; one of the first roller and the second roller moves upward and downward together with the other by moving the first support member upward and downward; one of the third roller and the fourth roller moves upward and downward together with the other by moving the second support member upward and downward; A stinger characterized by:

12. A stinger installed at the stern of a ship and guiding a pipeline, A first roller; A second roller; A third roller; A fourth roller; a support member that supports the first roller, the second roller, the third roller, and the fourth roller; Equipped with the pipeline is supported by the first roller and the second roller, and the third roller and the fourth roller; the first roller, the second roller, the third roller, and the fourth roller all move upward and downward by moving the support member upward and downward; A stinger characterized by:

13. A method for attaching a stinger according to any one of claims 1 to 7, comprising: a moving step of moving one of the first roller and the second roller together with the other roller upward and downward in response to stress in the pipeline; an attachment step of attaching the stinger to the stern; A method for attaching a stinger, comprising:

14. The attaching step is performed after the moving step.

14. The method of claim 13, wherein the method comprises:

15. The attaching step is performed before the moving step.

14. The method of claim 13, wherein the method comprises:

Images