Support system, support member

Abstract

The present invention provides a support member, a support system, and a method for installing a support member that can suppress the sinking of the member into the seabed and ensure a safe distance between the newly constructed pipeline and existing obstacles. [Solution] The support member 10 is installed between the new pipeline 1 and the seabed and is installed on the seabed, in order to install the new pipeline 1 on the seabed above the existing obstacle, intersecting the obstacle in a plan view and spaced apart from the obstacle, and includes a plate-shaped floor portion 11 installed on the seabed and a receiving portion 12 provided above the floor portion 11 to receive the new pipeline 1 from below.

Description

Technical Field

[0001] The present disclosure relates to a support member, a support system, and a method for installing a support member.

Background Art

[0002] [[ID=1Z]]New pipelines are being laid so as to straddle existing obstacles such as pipes or underwater cables laid on the seabed or the like. Patent Document 1 discloses laying an underwater pipe so as to straddle a pipe already laid on the seabed using a member (katatsu) having a base composed of tubular pieces.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The member disclosed in Patent Document 1 may sink into the seabed due to the weight of the member itself and the weight of the new pipeline supported by the member, and it may not be possible to ensure a separation between the new pipeline and the existing obstacle.

[0005] An object of the present disclosure is to provide a support member, a support system, and a method for installing a support member that can suppress the member from sinking into the seabed and ensure a separation between the new pipeline and the existing obstacle.

Means for Solving the Problems

[0006] A support member according to one aspect of the present disclosure is a support member installed between a new pipeline and the seabed in order to install a new pipeline on the seabed above an existing obstacle, intersecting the obstacle in a plan view and spaced apart from the obstacle, and comprising a plate-shaped floor portion installed on the seabed and a receiving portion provided above the floor portion to receive the new pipeline from below. [Effects of the Invention]

[0007] According to this disclosure, it is possible to provide a support member, a support system, and a method for installing a support member that can suppress the sinking of the member into the seabed and ensure the separation between the newly constructed pipeline and existing obstacles. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic overall diagram showing the situation in which a new pipeline is being laid using a support member according to one embodiment of the present disclosure. [Figure 2] This is a plan view showing the state of laying a new pipeline using the support member according to the same embodiment. [Figure 3] This is a front view showing a newly constructed pipeline being laid using the support member according to the same embodiment. [Figure 4] This is a front view of the support member according to the same embodiment. [Figure 5] This is a plan view of the support member according to the same embodiment. [Figure 6] This is a side view of the support member according to the same embodiment. [Figure 7] This is a front view illustrating the state of the support member during installation according to the same embodiment. [Modes for carrying out the invention]

[0009] When laying pipelines on the seabed, for example, existing pipelines on the seabed may make it difficult to lay new pipelines. Therefore, it is desirable to lay new pipelines on the seabed without contacting such existing pipelines. Furthermore, it is desirable to avoid interference with existing pipelines not only during the laying of the new pipeline, but also during operation after laying.

[0010] <Support member> A support member 10 in one embodiment of this disclosure will be explained with reference to Figures 1 to 7. The support member 10 according to this embodiment is installed on the seabed G. The support member 10 may be used not only in the sea, but also in water, lakes, etc. The support member 10 is also called a sleeper. Figure 1 is a schematic overall view showing the situation in which a new pipeline 1 is laid on the seabed G using the support member 10 according to this embodiment. The support member 10 is transported to the seabed G from a crane 51 mounted on a crane ship 50. The new pipeline 1 is sent out to the sea surface from a laying ship 30 and laid on the seabed G, for example, at a depth of about 80m, while the laying ship 30 moves forward.

[0011] Figure 2 is a plan view showing the state in which the new pipeline 1 is being laid using the support members 10. As shown in Figure 2, the support members 10 are positioned so that the new pipeline 1 intersects with the obstacle 4 in a plan view, above the existing obstacle 4. The obstacle 4 is an existing obstacle already submerged in the seabed G, and examples include pipelines, cables, rocks, and depressions used to transport natural gas or oil. In this embodiment, the case where the obstacle 4 is an existing pipeline 4A will be described. The existing pipeline 4A is, for example, a long pipe with a circular cross-section. Figure 3 is a front view showing the new pipeline 1 being laid using the support member 10. More specifically, Figure 3 is a front view of the support member 10. That is, Figure 3 is a view of the support member 10 from the longitudinal direction (X direction). Here, the longitudinal direction of the support member 10 is the X direction, the short direction (width direction) of the support member 10 is the Y direction, and the direction perpendicular to the X and Y directions is the Z direction. The Z direction is the vertical direction. As shown in Figure 3, the support member 10 is installed on the seabed G at a distance from the obstacle 4. The support member 10 is installed at a distance from the existing pipeline 4A in the Y direction. In this embodiment, multiple support members 10 are arranged on both sides of the existing pipeline 4A in the Y direction. Specifically, two support members 10 are arranged on each side of the existing pipeline 4A, for a total of four support members 10. The number of support members 10 is not limited to four. These support members 10 are arranged parallel to each other in a plan view, but are not limited to this. The support members 10 are installed between the new pipeline 1 and the seabed G.

[0012] Figures 4 to 6 show an example of the support member 10. Figure 4 is a front view of the support member 10, Figure 5 is a top view of the support member 10, and Figure 6 is a side view of the support member 10. The support member 10 comprises a floor portion 11 and a receiving portion 12. The floor section 11 is installed on the seabed G. The floor section 11 is plate-shaped. In this embodiment, the shape of the floor section 11 in plan view is, for example, rectangular. When the floor section 11 is rectangular, the length X11 in the longitudinal direction (X direction) is, for example, 15,000 mm to 25,000 mm, and the length Y11 in the transverse direction (Y direction) is, for example, 2,500 mm to 3,500 mm. The thickness Z11 of the floor section 11 (Z direction) is, for example, 5 mm to 15 mm. The material of the floor section 11 is, for example, carbon steel. The shape of the floor section 11 in plan view may be, for example, round, elliptical, or polygonal.

[0013] The support section 12 is provided above the floor section 11 in the Z direction and receives the newly installed pipeline 1 from below. The support section 12 comprises a plurality of support columns 13 (first support column 13A, second support column 13B) erected on the floor section 11, and an arrangement section 14 provided across one support column 13 (first support column 13A) and the other support column 13 (second support column 13B). The first support column 13A and the second support column 13B extend upward (Z direction) on the floor section 11. The arrangement section 14 extends in the longitudinal direction of the floor section 11, and both ends are supported by the first support column 13A and the second support column 13B. In this embodiment, the first support column 13A and the second support column 13B are installed at intervals in the longitudinal direction of the floor section 11. In this embodiment, two support columns 13 (first support column 13A, second support column 13B) are arranged, but the number of support columns is not limited to two. For example, three or more support columns may be installed along the longitudinal direction of the floor section 11. The newly installed pipeline 1 is placed on the upper surface of the arrangement section 14. The longitudinal length (X direction) X12 of the receiving portion 12 is, for example, 10,000 mm to 20,000 mm. The material of the receiving portion 12 is, for example, carbon steel. The arrangement portion 14 of the receiving portion 12 is, for example, a cylindrical pipe. If the receiving portion 12 is a cylindrical pipe, the diameter D14 of this pipe is, for example, 350 mm to 450 mm. The receiving portion 12 is not limited to a cylindrical shape; it may also be, for example, a plate shape.

[0014] The newly installed pipeline 1 is positioned to abut against the upper surface of the receiving portion 12 of the support member 10 and to intersect with the existing pipeline 4A above it. At the point where the new pipeline 1 and the existing pipeline 4A intersect, these pipelines are spaced apart in the Z direction.

[0015] The floor portion 11 of the support member 10 according to the present embodiment is plate-shaped, and this plate-shaped floor portion 11 is configured to be installed on the seabed G. Since the floor portion 11 is plate-shaped, the ground contact area of the floor portion 11 with the seabed G can be increased, and the load per unit area acting on the seabed G can be reduced. When the floor portion 11 is, for example, tubular, the area in contact with the seabed G becomes small, so the load per unit area acting on the seabed G increases. When the floor portion 11 is tubular, compared with the plate shape, the support member 10 is likely to sink into the seabed G. The support member 10 according to the present embodiment can reduce the ground settlement of the newly installed pipeline 1 because the floor portion 11 is plate-shaped. In addition, since the newly installed pipeline 1 is configured to be installed in a state separated from the existing obstacles, the separation between the pipeline 1 and the existing obstacles can be ensured not only during the laying of the newly installed pipeline but also during the operation after laying.

[0016] The longitudinal direction of the floor portion 11 of the support member 10 may extend in the extending direction of the existing pipeline 4A (obstacle 4).

[0017] As the support member 10 moves away from the existing pipeline 4A, the newly installed pipeline 1 may bend toward the seabed G side. In this case, the newly installed pipeline 1 may approach or contact the existing pipeline 4A. In the present embodiment, the support member 10 is arranged such that the floor portion 11 extends in the extending direction of the existing pipeline 4A. Thereby, the support member 10 (receiving portion 12) can be arranged closer to the existing pipeline 4A, so that the bending of the newly installed pipeline 1 can be reduced and it becomes possible to make it difficult for the newly installed pipeline 1 to contact the existing pipeline 4A.

[0018] The receiving portion 12 of the support member 10 may extend in the extending direction of the existing pipeline 4A (obstacle 4). In the present embodiment, the longitudinal direction of the floor portion 11 and the longitudinal direction of the receiving portion 12 are the same direction. The longitudinal direction of the floor portion 11 and the longitudinal direction of the receiving portion 12 do not have to be the same direction.

[0019] When positioning the newly laid pipeline 1 on the support section 12, it is required to ensure that the newly laid pipeline 1 is securely positioned on the support section 12. However, in actual laying operations, it is not easy to ensure that the newly laid pipeline 1 on the seabed G is securely positioned on the support section 12. In this embodiment, the support section 12 of the support member 10 is long in the direction of extension of the existing pipeline 4A, intersecting it above the existing pipeline 4A. This allows for adjustments to be made to errors caused by the laying of the new pipeline 1.

[0020] The newly installed pipeline 1 does not need to be fixed to the receiving portion 12. The newly installed pipeline 1 is positioned so as to be in contact with the upper surface of the receiving portion 12 (more specifically, the placement portion 14). For example, the fluid flowing inside the newly installed pipeline 1 may cause the pipeline 1 to move in the longitudinal direction of the receiving portion 12. Therefore, it is desirable that the newly installed pipeline 1 be movable in the longitudinal direction of the receiving portion 12 while it is positioned on the receiving portion 12. In this way, the receiving portion 12 allows the newly installed pipeline 1 to move in the longitudinal direction of the receiving portion 12 while supporting the pipeline 1 from below.

[0021] The newly installed pipeline 1 allows for longitudinal movement of the receiving portion 12. This prevents the generation of stress due to longitudinal movement of the newly installed pipeline 1.

[0022] The longitudinal length X11 of the floor portion 11 may be greater than or equal to the longitudinal length X12 of the receiving portion 12. The longitudinal length X11 of the floor portion 11 may be adjustable by hinges or telescopic mechanisms (neither of which are shown).

[0023] By making the longitudinal length X11 of the floor portion 11 greater than or equal to the longitudinal length X12 of the receiving portion 12, the support member 10 can be stably positioned on the seabed G.

[0024] The floor section 11 may extend in the shorter direction (Y direction). By making the floor section 11 longer in the shorter direction, the area of ​​the floor section 11 increases, so that the support member 10 can be placed more stably on the seabed G.

[0025] The receiving portion 12 (more specifically, the placement portion 14) may be provided above the floor portion 11, spaced apart from the floor portion 11.

[0026] By positioning the receiving portion 12 above the floor portion 11, at a distance from the floor portion 11, the new pipeline 1 and the existing pipeline 4A can be separated. This makes it difficult for the new pipeline 1 to come into contact with the existing pipeline 4A.

[0027] The support member 10 may include a height adjustment mechanism 15 for adjusting the height H12 (mm) of the receiving portion 12 relative to the floor portion 11. The height H12 of the receiving portion 12 is the distance from the floor portion 11 to the receiving portion 12 in the Z direction. More specifically, the height H12 of the receiving portion 12 is the distance from the upper surface of the floor portion 11 to the center of the receiving portion 12 (more specifically, the placement portion 14) in the Z direction. The height H12 of the receiving portion 12 is, for example, between 200 mm and 1000 mm.

[0028] The height adjustment mechanism 15 allows for maintaining an appropriate separation distance between the new pipeline 1 and the existing pipeline 4A. Although the height H12 is adjusted in advance based on the height results of the preliminary ground survey, there may be cases where the actual values ​​differ from the calculated or observed values ​​on site, resulting in some support members 10 not making contact with the new pipeline 1. By providing the height adjustment mechanism 15, the height H12 can be adjusted after the new pipeline 1 is laid, allowing all the designed support members 10 to make contact.

[0029] The height adjustment mechanism 15 adjusts the vertical position (Z-direction) of the mounting section 14 relative to the support column 13. The height adjustment mechanism 15 is provided on the support column 13. The height adjustment mechanism 15 can also adjust the height H12 using, for example, a jack or a floater (but only in water). The height adjustment mechanism 15 can also fix the height H12 using, for example, a bolt (or pin, etc.).

[0030] The height adjustment mechanism 15 allows for maintaining an appropriate distance between the newly installed pipeline 1 and the existing pipeline 4A. Furthermore, since the height adjustment mechanism 15 can adjust the vertical position of the placement section 14 relative to the support column 13, the height H12 can be adjusted after the new pipeline 1 is laid, allowing all of the designed support members 10 to come into contact with it.

[0031] The height adjustment mechanism 15 may be provided at both ends of the arrangement section 14. The height adjustment mechanism 15 may be provided between the end of the arrangement section 14 on the side of one support column 13 (first support column 13A) and the first support column 13 (second support column 13B), and between the end of the arrangement section 14 on the side of the other support column 13 (second support column 13B) and the other support column 13 (second support column 13B). One height adjustment mechanism 15 (first height adjustment mechanism 15A) and the other height adjustment mechanism 15 (second height adjustment mechanism 15B) are configured to be adjustable independently. In the illustrated example, for example, cylindrical bodies are provided at each end of the arrangement section 14, and these cylindrical bodies function as height adjustment mechanisms 15 (first height adjustment mechanism 15A, second height adjustment mechanism 15B). The cylindrical bodies are movable vertically on the support column 13, and their vertical position can be fixed relative to the support column 13 by means of, for example, a pin. Specifically, the height of the height adjustment mechanism 15 and the arrangement section 14 relative to the floor section 11 is fixed by inserting a pin that passes through the support column 13 and the height adjustment mechanism 15.

[0032] The first height adjustment mechanism 15A and the second height adjustment mechanism 15B allow the height H12 of both ends of the installation section 14 to be adjusted separately, thereby enabling a more appropriate separation distance between the newly installed pipeline 1 and the existing pipeline 4A. Furthermore, even if there is a difference in elevation in the seabed G below the floor section 11, the difference in elevation in the seabed G can be accommodated by adjusting the first height adjustment mechanism 15A and the second height adjustment mechanism 15B separately.

[0033] The support member 10 is installed on the seabed G by a crane 51 mounted on a crane ship 50. Figure 7 shows a front view illustrating the state of the support member 10 during installation. If the laying ship 30 is equipped with a crane, the support member 10 may be lowered to the seabed G by the laying ship 30 (crane ship) equipped with a crane. The support member 10 may include a mounting portion 16 to which the lifting device 52 of the crane 51 can be attached. In this embodiment, the mounting portion 16 is provided at the upper end of the first support column 13A and the upper end of the second support column 13B. The mounting portion 16 is, for example, a base having a through hole through which a bolt can pass. The lifting device 52 is, for example, a wire. For example, an annular portion is provided at one end of the wire, and the support member 10 and the wire are connected by connecting the annular portion to a bolt (the bolt is inserted into the annular portion). The other end of the wire is connected to the crane 51. The upper part of the lifting device 52 shown in Figure 7 is connected to a crane 51, and the crane 51 is used to transport the support member 10 to the seabed G. The mounting portion 16 may be provided on the floor portion 11. In this case, for example, the mounting portion 16 may be provided on both ends in the longitudinal direction of the floor portion 11. Alternatively, the receiving portion 12 may function as the mounting portion 16. Specifically, for example, the lifting device 52 of the crane 51 may be connected to the arrangement portion 14.

[0034] The mounting portion 16 connects the support member 10 to the crane 51. This allows the support member 10 to be transported to the seabed G.

[0035] The support member 10 may include a sacrificial anode 18. In this embodiment, the sacrificial anode 18 is provided on both ends in the longitudinal direction of the floor portion 11. The location where the sacrificial anode 18 is provided is not limited to the floor portion 11; for example, it may be provided on the support column 13 or the receiving portion 12. Note that a known sacrificial anode can be used for the sacrificial anode 18.

[0036] The support member 10 is equipped with a sacrificial anode 18, which protects the support member 10 from corrosion caused by seawater.

[0037] The support member 10 may be positioned parallel or approximately parallel to the obstacle 4 (existing pipeline 4A) in a plan view.

[0038] By arranging the support members 10 parallel to or approximately parallel to the existing pipeline 4A, the distance between the support members 10 that straddle the obstacle 4 can be shortened in a plan view. This suppresses the deflection of the new pipeline 1 between the support members 10 that straddle the obstacle 4, and reduces the possibility of the support members 10 coming into contact with the existing pipeline 4A. Furthermore, when multiple support members 10 are installed, the possibility of adjacent support members 10 coming into contact with each other can be reduced. In addition, by arranging the support members 10 parallel to or approximately parallel to the existing pipeline 4A, the distance between the support members 10 can be made uniform regardless of the seating position of the new pipeline 1 on the receiving portion 12. If the support members 10 are not arranged parallel to or approximately parallel to the existing pipeline 4A, the distance between the support members 10 will change depending on the seating position of the new pipeline 1 on the receiving portion 12, making management difficult. The support members 10 do not necessarily have to be arranged parallel to or approximately parallel to the existing pipeline 4A in a plan view. In this case, the possibility of contact can be reduced by keeping the support members 10 and the existing pipeline 4A sufficiently far apart. Although Figure 2 shows that the support member 10 is positioned parallel to the existing pipeline 4A, in the actual seabed G, it is possible that the support member 10 may not be positioned strictly parallel as shown in Figure 2. In this disclosure, the positioning of the support member 10 parallel or approximately parallel to the existing pipeline 4A means that the support member 10 is substantially parallel or approximately parallel to the existing pipeline 4A in the seabed G. For example, the positioning of the support member 10 parallel or approximately parallel to the existing pipeline 4A means that the angle between the longitudinal direction of the support member 10 and the longitudinal direction of the existing pipeline 4A is within ±5°.

[0039] <Support System> A support system J10 according to one embodiment of the present disclosure comprises a plurality of support members 10 according to the above-described embodiment. In the support system J10, in a plan view, the plurality of support members 10 are arranged to surround an obstacle 4 (for example, an existing pipeline 4A). In the example shown in Figures 1 to 3, two support members 10 are placed on each side of the existing pipeline 4A, resulting in a total of four support members 10 (10A-1, 10A-2, 10B-1, 10B-2). The multiple support members 10 are arranged symmetrically with respect to the obstacle 4. However, the multiple support members 10 are not necessarily arranged symmetrically with respect to the obstacle 4. The multiple support members 10 include a first support member (first A support member) 10A-1 closest to the existing pipeline 4A in a plan view, and a second support member (second A support member) 10A-2 adjacent to the first support member 10A-1. For example, as shown in Figures 1 to 3, in a plan view, the first A support member 10A-1 and the second A support member 10A-2 are arranged to the left of the existing pipeline 4A in order of proximity to the existing pipeline 4A, and the first B support member 10B-1 and the second B support member 10B-2 are arranged to the right of the existing pipeline 4A in order of proximity to the existing pipeline 4A.

[0040] The number of support members 10 is not limited to four. For example, three support members 10 may be placed on each side of the existing pipeline 4A, resulting in a total of six support members 10 distributed around the pipeline 4A. In this case, in a plan view, the 1st A support member 10A-1, the 2nd A support member 10A-2, and the 3rd A support member 10A-3 (not shown) are placed on the left side of the existing pipeline 4A in order of proximity to the pipeline 4A, and the 1st B support member 10B-1, the 2nd B support member 10B-2, and the 3rd B support member 10B-3 (not shown) are placed on the right side of the existing pipeline 4A in order of proximity to the pipeline 4A. Alternatively, for example, three support members 10 may be placed on one side of the existing pipeline 4A, and one support member 10 may be placed on the other side, resulting in a total of four support members 10 distributed around the pipeline 4A. In this case, for example, in a plan view, the first A support member 10A-1, the second A support member 10A-2, and the third A support member 10A-3 (not shown) are arranged to the left of the existing pipeline 4A in order of proximity to the existing pipeline 4A, and the first B support member 10B-1 is arranged to the right of the existing pipeline 4A.

[0041] The distances between adjacent support members 10 may be equal. For example, in the example in Figure 2, distance L10 (mm), distance L10A-1 (mm), and distance L10B-1 (mm) may be equal. When these distances are equal, they are, for example, between 10,000 mm and 20,000 mm. Distance L10 is the distance between the first A support member 10A-1 and the first B support member 10B-1. Distance L10A-1 is the distance between the first A support member 10A-1 and the second A support member 10A-2. Distance L10B-1 is the distance between the first B support member 10B-1 and the second B support member 10B-2. Furthermore, in the example shown in Figure 2, it is preferable that distance L4A (mm) and distance L4B (mm) are equal. That is, it is preferable to position the first A support member 10A-1 and the first B support member 10B-1 such that the existing pipeline 4A is centered between them. For example, if distance L10 is 17400 mm, then distances L4A and L4B are 8700 mm each. Distance L10A-1 may be shorter than distance L4A. These distances L10, L10A-1, and L10B-1 are the distances between the longitudinal centers of the support members 10 in the longitudinal direction of the new pipeline 1 in a plan view, as shown in Figure 2. Distances L4A and L4B are the distances from the intersection of the new pipeline 1 and the existing pipeline 4A to each support member 10 (10A-1, 10B-1) in the longitudinal direction of the new pipeline 1 in a plan view, as shown in Figure 2. Note that the spacing between adjacent support members 10 does not have to be equal. Also, distance L4A (mm) and distance L4B (mm) do not have to be equal.

[0042] Since multiple support members 10 are distributed and positioned on either side of the existing pipeline 4A, the new pipeline 1 is positioned to straddle the existing pipeline 4A. This configuration allows for maintaining an appropriate distance between the new pipeline 1 and the existing pipeline 4A.

[0043] The receiving portion 12 (more specifically, the placement portion 14) may be provided above the floor portion 11, spaced apart from the floor portion 11. In multiple support members 10, the height H12 of the receiving portion 12 (more specifically, the placement portion 14) relative to the floor portion 11 in the support member 10 may be set to multiple values.

[0044] The height H12 of the receiving portion 12 may differ depending on the number of support members 10. For example, if the seabed G is gentle (horizontal), the height of the receiving portion 12 relative to the floor portion 11 of the first support member (first A support member) 10A-1 is higher than the height of the receiving portion 12 relative to the floor portion 11 of the second support member (second A support member) 10A-2. The height H12 of the receiving portion 12 of the first A support member 10A-1 is set higher than the height H12 of the second A support member 10A-2. In this way, the height H12 of the receiving portion 12 of the support member 10 is set lower as it moves away from the existing pipeline 4A. By setting it in this way, it becomes possible to position the new pipeline 1 so that it is less likely to come into contact with the existing pipeline 4A, and the degree of curvature of the new pipeline 1 can be made gentler.

[0045] The support member 10 may be configured to allow setting the height H12 of the receiving portion 12 (more specifically, the placement portion 14) based on the undulations of the seabed G. For example, when the support member 10 is placed in a position where the seabed G is sinking, the height H12 of the receiving portion 12 is set higher than that of the support member 10 placed in a position where the seabed G is not sinking. Also, for example, when the support member 10 is placed in a position where the seabed G is rising, the height H12 of the receiving portion 12 is set lower than that of the support member 10 placed in a position where the seabed G is not rising. In this way, when the seabed G is undulating, the support member 10 is placed on the seabed G such that the curvature of the newly constructed pipeline 1 is gentle in the Z direction.

[0046] The support member 10 allows the height H12 of the receiving portion 12 to be set based on the undulations of the seabed G. This enables proper support of the newly constructed pipeline 1 in the Z direction.

[0047] A support system (not shown) according to one embodiment of the present disclosure comprises a support member 10 according to the above-described embodiment. In a plan view, the support member 10 is positioned on one side of an obstacle (e.g., an existing pipeline 4A). For example, one support member 10 (e.g., a first A support member 10A-1) is positioned on only one side of the existing pipeline 4A. Two or more support members 10 (e.g., a first A support member 10A-1 and a second A support member 10A-2) may be positioned on only one side of the existing pipeline 4A.

[0048] If the support member 10 cannot be placed on one side of the existing pipeline 4A, for example, if the seabed G on one side of the existing pipeline 4A is a deep valley, it is difficult to place the support member 10 in the deep valley. In this case, by placing the support member 10 only on one side of the existing pipeline 4A (the side where the seabed G is not a deep valley), the appropriate distance between the new pipeline 1 and the existing pipeline 4A can be maintained.

[0049] <Method for installing support members> The method for installing the support member 10 will be explained below. The method for installing the support member 10 is a method for installing the support member 10 on the seabed G, which is to be installed between the new pipeline 1 and the seabed G, in order to install the new pipeline 1 above the existing obstacle 4 (for example, the existing pipeline 4A) on the seabed G in a state where it intersects with the obstacle 4 in a plan view and is spaced apart from the obstacle 4. The method for installing the support member 10 includes a lowering step.

[0050] The lowering process is the process of lowering the support member 10 to the seabed G by a crane ship 50. The crane ship 50 is equipped with a crane 51. The crane 51 is, for example, a slewing type. A wire is connected to the tip of the crane 51. The support member 10 is connected to the other end of the wire opposite to the end to which the crane 51 is connected. In the lowering process, the support member 10 is lowered to the seabed G by the crane 51. The support member 10 may be installed before the start of laying the new pipeline 1. If the laying ship 30 is equipped with a crane, the lowering process is the process of lowering the support member 10 to the seabed G by the laying ship 30 (crane ship) equipped with a crane. The lowering process by the laying ship 30 (crane ship) may be performed during the laying of the new pipeline 1.

[0051] According to the method of installing the support member 10, the support member 10 can be lowered to the seabed G by the crane ship 50 and installed on the seabed G above the existing obstacle 4, intersecting with the obstacle 4 in a plan view, and at a distance from the obstacle 4. Therefore, it becomes possible to stably lay the new pipeline 1 on the seabed G.

[0052] The method for installing the support member 10 may further include a loading step of placing the support member 10 on a barge 56. The barge 56 is positioned close to the crane ship 50. The lowering step involves lowering the support member 10 from the barge 56 to the seabed G by the crane ship 50. The step of transferring the support member 10 to the barge 56 is not required. Alternatively, the support member 10 may be transferred from the barge 56 to the laying ship 30 and installed from the laying ship 30 equipped with a crane, or the support member 10 may be transferred from the barge 56 to the crane ship 50 and installed from the crane ship 50.

[0053] By providing the barge 56, it can be used as a place to store the support members 10, and the deck of the crane ship 50 can be used effectively. However, the barge 56 is not required.

[0054] In the installation method for the support member 10, a lowering process may be performed after the placement process.

[0055] In the loading process, the support members 10 are pre-loaded onto a barge 56 adjacent to the crane ship 50, and then, in the lowering process, the support members 10 are lowered to the seabed G by the crane ship 50. This allows the loading and lowering processes to proceed smoothly.

[0056] The loading process and the lowering process may be carried out in parallel.

[0057] By performing the installation process and the lowering process in parallel, the time required for the construction of the support member 10 can be shortened.

[0058] As shown in Figure 7, the crane ship 50 may also suspend the support member 10 via a lifting beam 57 (spreader bar). The lifting beam 57 is positioned between the crane 51 and the support member 10. The support member 10 may be installed without the lifting beam 57.

[0059] The support member 10 is suspended by a suspension beam 57. This allows the support member 10 to be suspended stably.

[0060] The support member 10 may be installed using a plurality of lifting beams 57 (57A, 57B). The lifting beams 57 include a first lifting beam 57A and a second lifting beam 57B. The first lifting beam 57A is installed on the crane 51 side, and the second lifting beam 57B is installed on the support member 10 side. The first lifting beam 57A and the second lifting beam 57B are connected by a wire. Of the multiple suspension beams (first suspension beam 57A, second suspension beam 57B), at least one suspension beam (first suspension beam 57A) may be located in the air when the support member 10 is in contact with the seabed G. As shown in Figure 7, the first suspension beam 57A is located above the sea surface H (towards the air).

[0061] The first lifting beam 57A, positioned in the air, serves as a landmark from the sea. Because the first lifting beam 57A serves as a landmark, the position of the support member 10 installed on the seabed G can be determined. Before the lowering process, a sonar transmitter (e.g., a beacon) may be attached to the support member 10 or the lower second lifting beam 57B. The crane ship 50 can receive the signal and confirm the position of the support member 10 on a monitor on the crane ship 50.

[0062] The method for installing the support member 10 may include a height adjustment step for adjusting the height of the support member 10. Specifically, the height H12 of the receiving portion 12 (more specifically, the placement portion 14) relative to the floor portion 11 is adjusted.

[0063] The height adjustment process allows the desired height of the support member 10 to be set. The height adjustment process may be performed before the lowering process and the installation process, in which case the support member 10 adjusted to the designed height can be prepared in advance. Alternatively, the height adjustment process may be performed after the lowering process and the installation process, in which case, if it is necessary to adjust the height of the support member 10 after it has been installed on the seabed G, the height can be adjusted as needed.

[0064] The technical scope of this disclosure is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of this disclosure. For example, the floor portion 11 of the support member 10 does not have to extend in the direction of the existing pipeline 4A (obstacle 4). The receiving portion 12 of the support member 10 does not necessarily have to extend in the direction of extension of the existing pipeline 4A (obstacle 4). The receiving portion 12 of the support member 10 does not necessarily have to be in a state where it is receiving the newly installed pipeline from below. The new pipeline 1 may also be fixed to the receiving portion 12. The longitudinal length X11 of the floor portion 11 of the support member 10 may be less than the longitudinal length X12 of the receiving portion 12. The receiving portion 12 (more specifically, the placement portion 14) does not need to be spaced apart from the floor portion 11. The support member 10 does not necessarily have a height adjustment mechanism 15 for adjusting the height H12 of the receiving portion 12 relative to the floor portion 11. The height adjustment mechanism 15 does not need to adjust the vertical position (Z direction) of the placement section 14 relative to the support columns 13 (first support column 13A, second support column 13B). The height adjustment mechanism 15 does not necessarily have to be provided at both ends of the arrangement section 14. The support member 10 does not necessarily have to have a mounting portion 16 to which the lifting device 52 of the crane 51 can be attached. The support member 10 does not necessarily have to include a sacrificial anode 18. The support member 10 does not necessarily have to be positioned parallel or approximately parallel to the obstacle 4 (existing pipeline 4A) in a plan view. The support member 10 does not necessarily need to be able to set the height H12 of the receiving portion 12 (more specifically, the placement portion 14) based on the undulations of the seabed G. The method for installing the support member 10 does not necessarily require a step of placing the support member 10 on the barge 56. The loading process and the lowering process do not necessarily have to be performed in parallel. The crane ship 50 does not need to suspend the support member 10 via the lifting beam 57. Of the multiple suspension beams (first suspension beam 57A, second suspension beam 57B), at least one suspension beam (first suspension beam 57A) does not need to be located in the air when the support member 10 is in contact with the seabed G. The method for installing the support member 10 does not necessarily require a height adjustment step for adjusting the height of the support member 10.

[0065] Furthermore, it is possible to replace the components in the above embodiments with well-known components as appropriate, without departing from the spirit of this disclosure, and the above-described modifications may be combined as appropriate.

[0066] (Note) The above embodiment can be understood, for example, as follows:

[0067] <1> A support member according to one aspect of the present disclosure is a support member installed between a new pipeline and the seabed in order to install a new pipeline on the seabed above an existing obstacle, intersecting the obstacle in a plan view and spaced apart from the obstacle, and comprising a plate-shaped floor portion installed on the seabed and a receiving portion provided above the floor portion to receive the new pipeline from below.

[0068] Because the floor section is plate-shaped, the floor area can be increased, reducing the load per unit area acting on the seabed. With a plate-shaped floor support member, ground subsidence of the newly constructed pipeline can be reduced, making it possible to stably lay the new pipeline on the seabed.

[0069] <2> the above <1> The support member may be configured such that the obstacle is a long object and the floor portion extends in the direction in which the obstacle extends.

[0070] Since the support members can be positioned closer to the existing pipeline, the curvature of the new pipeline can be reduced, making it less likely for the new pipeline to come into contact with the existing pipeline.

[0071] <3> the above <2> The support member may adopt a configuration in which the receiving portion extends in the direction in which the obstacle extends.

[0072] This configuration allows for adjustments to be made to errors caused by the laying of new pipelines, and also facilitates positioning of new pipelines in the longitudinal center of the receiving section.

[0073] <4> the above <3> The support member may be configured such that the receiving portion supports the newly installed pipeline from below and allows movement of the newly installed pipeline in the longitudinal direction of the receiving portion.

[0074] This configuration allows for adjustments to be made to errors caused by the laying of new pipelines, and also facilitates positioning of new pipelines in the longitudinal center of the receiving section.

[0075] <5> the above <4> The support member may be configured such that the longitudinal length of the floor portion is equal to or greater than the longitudinal length of the receiving portion.

[0076] This configuration increases the floor area, allowing the support members to be stably positioned on the seabed.

[0077] <6> the above <1> from <5> The support member relating to any one of the above may be configured such that the receiving portion is provided above the floor portion, with the receiving portion spaced apart from the floor portion.

[0078] This configuration allows for a separation between the newly constructed pipeline and the existing pipeline, making it less likely for the new pipeline to come into contact with the existing pipeline.

[0079] <7> the above <6> The support member may be configured to include a height adjustment mechanism for adjusting the height of the receiving portion relative to the floor portion.

[0080] The height adjustment mechanism allows for maintaining an appropriate distance between the newly installed pipeline and the existing pipeline.

[0081] <8> the above <7> The support member relating to this may have a receiving portion comprising a plurality of support columns erected on the floor and an arrangement portion provided across one of the support columns and another, and the height adjustment mechanism may be configured to adjust the vertical position of the arrangement portion relative to the support columns.

[0082] The height adjustment mechanism allows for maintaining an appropriate distance between the newly installed pipeline and the existing pipeline.

[0083] <9> the above <8> The support member may be configured such that the height adjustment mechanism is provided between one end of the support column in the arrangement section and one of the support columns, and between the other end of the support column in the arrangement section and the other support column, and the height adjustment mechanism and the other height adjustment mechanism are configured to be adjustable separately.

[0084] Since the height of both ends of the installation section can be adjusted independently, the distance between the newly installed pipeline and the existing pipeline can be maintained more appropriately.

[0085] <10> the above <1> from <5> The support member relating to any one of the above may be configured to include a mounting portion to which a crane lifting device can be attached.

[0086] The mounting section connects the support member to the crane. This allows the support member to be transported to the seabed.

[0087] <11> the above <1> from <5> The support member relating to any one of the above may be configured to include a sacrificial anode.

[0088] By incorporating a sacrificial anode, the support members can be more easily protected from corrosion by seawater.

[0089] <12> the above <1> from <5> The support member relating to any one of the above may be configured such that the obstacle is a long object, and the support member is positioned parallel or substantially parallel to the obstacle in a plan view.

[0090] This configuration reduces the possibility of the support members coming into contact with existing pipelines. Furthermore, when multiple support members are installed, the possibility of adjacent support members coming into contact with each other is also reduced.

[0091] <13> the above <1> from <5> A support system comprising a plurality of support members relating to any one of the above, wherein the plurality of support members are arranged to be separated on either side of the obstacle.

[0092] Because multiple support members are distributed and positioned on either side of the existing pipeline, the new pipeline is positioned to straddle the existing pipeline. This configuration allows for maintaining an appropriate distance between the new pipeline and the existing pipeline.

[0093] <14> the above <13> The support system relating to this may be configured such that the receiving portion is provided above the floor portion at a distance from the floor portion, and in a plurality of support members, the height of the receiving portion of the support member relative to the floor portion can be set to multiple values.

[0094] The height of the receiving portion may differ depending on the support member. For example, the height of the receiving portion of the support member may be set lower as it moves further away from the existing pipeline. By setting it in this way, it becomes possible to position the new pipeline without it coming into contact with the existing pipeline, and the degree of curvature of the new pipeline can be made gentler.

[0095] <15> the above <14> The support system may employ a configuration that allows the height of the receiving portion to be set based on the undulations of the seabed.

[0096] This configuration allows for proper support of the newly constructed pipeline in the Z direction.

[0097] <16> the above <1> from <5> A support system comprising the support member relating to any one of the above, wherein the support member is positioned on one side of the obstacle.

[0098] If it is not possible to place support members on one side of an existing pipeline, for example, if the seabed on one side of the existing pipeline is a deep valley, it is difficult to place support members in a deep valley. In this case, by placing support members on only one side of the existing pipeline, the appropriate distance between the new pipeline and the existing pipeline can be maintained.

[0099] <17> A method for installing a support member to be installed on the seabed, which is to be installed between the new pipeline and the seabed, in order to install the new pipeline on the seabed above an existing obstacle, in a state where it intersects with the obstacle in a plan view and is spaced apart from the obstacle, comprising a lifting step of lowering the support member to the seabed by a crane vessel.

[0100] With this configuration, the support members can be lowered to the seabed by a crane ship and installed on the seabed above existing obstacles, intersecting them in a plan view, while also being spaced away from them. Therefore, it becomes possible to stably lay the new pipeline on the seabed.

[0101] <18> the above <17> The method for installing the support member relating to the above may include a placement step of placing the support member on a barge, and the lowering step may be configured to lower the support member on the barge to the seabed using a crane vessel.

[0102] By providing a barge, it can be used as a storage area for support members, and the deck of the crane ship can be used effectively.

[0103] <19> the above <18> The method for installing the support member may be configured such that the lowering step is performed after the installation step described above.

[0104] In the loading process, the support members are pre-loaded onto a barge adjacent to the crane ship, and then, in the lowering process, the support members are lowered to the seabed by the crane ship. This allows for a smooth transition from the loading process to the lowering process.

[0105] <20> the above <19> The method for installing the support member may be configured such that the installation step described above and the lowering step are performed in parallel.

[0106] By performing the installation and lowering processes in parallel, the time required for the construction of the support members can be reduced.

[0107] <21> the above <17> from <20> The method for installing the support member according to any one of the above items may involve the crane ship suspending the support member via a lifting beam.

[0108] The support member is suspended by a balance beam. This allows the support member to be suspended stably.

[0109] <22> the above <21> The method for installing the support member may include a plurality of the aforementioned suspension beams, wherein at least one of the plurality of suspension beams (the first suspension beam) is positioned in the air when the support member is resting on the seabed.

[0110] The first suspension beam, positioned in the air, serves as a landmark from the sea. Because the first suspension beam acts as a landmark, the location of the support members installed on the seabed can be determined.

[0111] <23> the above <17> from <20> The method for installing a support member according to any one of the above items may include a height adjustment step for adjusting the height of the support member.

[0112] The height adjustment process allows for setting the desired height of the support members. The height adjustment process may be performed before the lowering and installation processes, in which case the support members adjusted to the designed height can be prepared in advance. Alternatively, the height adjustment process may be performed after the lowering and installation processes, in which case, if it is necessary to adjust the height of the support members after they have been installed on the seabed, the height can be adjusted as needed. [Explanation of symbols]

[0113] 1. Newly constructed pipeline 4 Obstacles 4A Existing pipeline 10 Support member 11 Floor 12 Receiving part 13 Posts 14 Placement section 15 Adjustment mechanism 16 Mounting part 18 Sacrificial Anode 50 Hoist Ship 51 Cranes 52 Hanging equipment 56 Barge 57 Balance G Undersea J10 Support System

Claims

1. A support member is installed between the new pipeline and the seabed in order to install the new pipeline on the seabed above an existing obstacle, intersecting the obstacle in a plan view, and spaced apart from the obstacle. The aforementioned plate-shaped floor section installed on the seabed, A support member comprising a receiving portion provided above the floor portion and receiving the newly installed pipeline from below.

2. The aforementioned obstacle is an elongated object, The floor portion is the support member according to claim 1, which extends in the direction in which the obstacle extends.

3. The support member according to claim 2, wherein the receiving portion extends in the direction in which the obstacle extends.

4. The support member according to claim 3, wherein the receiving portion supports the newly installed pipeline from below and allows movement of the newly installed pipeline in the longitudinal direction of the receiving portion.

5. The support member according to claim 4, wherein the longitudinal length of the floor portion is greater than or equal to the longitudinal length of the receiving portion.

6. The support member according to any one of claims 1 to 5, wherein the receiving portion is provided above the floor portion in a state where it is spaced apart from the floor portion.

7. The support member according to claim 6, further comprising a height adjustment mechanism for adjusting the height of the receiving portion relative to the floor portion.

8. The receiving portion comprises a plurality of support columns erected on the floor and an arrangement portion provided across one support column and another support column. The support member according to claim 7, wherein the height adjustment mechanism adjusts the vertical position of the arrangement portion with respect to the support column.

9. The height adjustment mechanism is provided between one end of the support column in the arrangement section and one of the support columns, and between the other end of the support column in the arrangement section and the other support column. The support member according to claim 8, wherein one of the height adjustment mechanisms and the other height adjustment mechanism are configured to be adjustable separately.

10. A support member according to any one of claims 1 to 5, comprising a mounting portion to which a crane lifting device can be attached.

11. A support member according to any one of claims 1 to 5, comprising a sacrificial anode.

12. The aforementioned obstacle is an elongated object, The support member according to any one of claims 1 to 5, wherein the support member is arranged parallel or substantially parallel to the obstacle in a plan view.

13. A support system comprising a plurality of support members according to any one of claims 1 to 5, A support system in which multiple support members are arranged to surround the obstacle.

14. The receiving portion is provided above the floor portion, spaced apart from the floor portion. The support system according to claim 13, wherein in a plurality of support members, the height of the receiving portion of the support member relative to the floor portion can be set to a plurality of values.

15. The support system according to claim 13, wherein the height of the receiving portion can be set based on the undulations of the seabed.

16. A support system comprising the support member according to any one of claims 1 to 5, The support member is a support system positioned on one side of the obstacle.

17. A method for installing a support member on the seabed to install a support member between the new pipeline and the seabed, in order to install the new pipeline on the seabed above an existing obstacle, in a state where it intersects with the obstacle in a plan view and is spaced apart from the obstacle, A method for installing a support member, comprising a lifting step of lowering the support member to the seabed using a crane vessel.

18. The process includes placing the support member onto a barge, The method for installing a support member according to claim 17, wherein the lowering step involves lowering the support member on the barge to the seabed using the crane vessel.

19. The method for installing a support member according to claim 18, wherein the lowering step is performed after the above-mentioned placement step is performed.

20. The method for installing a support member according to claim 19, wherein the above-mentioned placement step and the above-mentioned lowering step are performed in parallel.

21. The method for installing a support member according to any one of claims 17 to 20, wherein the crane vessel suspends the support member via a lifting beam.

22. Equipped with multiple of the aforementioned suspension beams, The method for installing a support member according to claim 21, wherein at least one of the multiple suspension beams is located in the air when the support member is resting on the seabed.

23. A method for installing a support member according to any one of claims 17 to 20, further comprising a height adjustment step for adjusting the height of the support member.

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