Method for tilting a structure and tilting structure

Abstract

To provide a structure tilting method and a structure for tilting capable of controlling at least one of structure tilting speed and tilting direction.SOLUTION: There is provided a structure tilting method for tilting a floor-mounted structure 200 extending upward from a ground 401, including an installation step of attaching a resistance member 110 that receives fluid force from water and air surrounding the structure 200 to the structure 200, and a tilting step of tilting the structure 200 to which the resistance member 110 is attached.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a method for tilting a structure and a tilting structure. [Background technology]

[0002] For example, when demolishing a land-based structure that extends vertically, such as a tower-type structure, a low-cost demolition method that avoids working at height as much as possible is to cut the base of the structure, topple it, and then demolish it (see, for example, Patent Document 1). The structure is cut using, for example, blasting or other mechanical cutting. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4828314 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if this type of demolition method is applied to a bottom-mounted floating structure, (1) when the structure collapses, waves may be created on the water surface, posing a danger to nearby ships and other vessels, (2) when and after the structure collapses, contaminants attached to the structure (debris, dust, oil, etc.) or contained in the structure may be scattered or washed out into the water, causing pollution, and (3) there is a possibility that the collapsed structure will sink into the water and become impossible to recover.

[0005] Furthermore, in order to safely tilt a structure when dismantling a tower-type structure, not limited to a floating structure, it is preferable to control at least one of the tilting speed and tilting direction of the structure.

[0006] The present disclosure has been made in consideration of these circumstances, and aims to provide a method for tilting a structure and a tilting structure that can control at least one of the tilting speed and tilting direction of the structure. [Means for solving the problem]

[0007] In order to solve the above problems, the method for tilting a structure and the tilting structure of the present disclosure employ the following means. In other words, a method for tilting a structure according to one aspect of the present disclosure is a method for tilting a fixed structure extending upward from the ground, and includes an installation step of attaching a resistance member to the structure that receives fluid force from the fluid surrounding the structure, and a tilting step of tilting the structure to which the resistance member is attached.

[0008] In addition, a tilting structure according to one aspect of the present disclosure comprises a bottom-mounted structure extending upward from the ground, and a resistance member attached to the structure and receiving fluid force from the fluid surrounding the structure. [Effects of the Invention]

[0009] According to the present disclosure, it is possible to control at least one of the tilting speed and tilting direction of a structure. [Brief explanation of the drawings]

[0010] [Figure 1] This is a diagram showing the floating structure before and after removal. [Figure 2] FIG. 1 is a front view of a tilting structure according to a first embodiment of the present disclosure. [Figure 3] FIG. 2 is a side view of the tilting structure according to the first embodiment of the present disclosure. [Figure 4] FIG. 1 is a front view of a tilting structure according to a first embodiment of the present disclosure. [Figure 5] FIG. 2 is a side view of the tilting structure according to the first embodiment of the present disclosure. [Figure 6] FIG. 10 is a front view of a tilting structure according to another example of the first embodiment of the present disclosure. [Figure 7] FIG. 10 is a side view of a tilting structure according to another example of the first embodiment of the present disclosure. [Figure 8]10A and 10B are diagrams illustrating a method for cutting a structure. [Figure 9] 10A and 10B are diagrams illustrating a method for cutting a structure. [Figure 10] 10A and 10B are diagrams illustrating a method for cutting a structure. [Figure 11] 10A and 10B are diagrams illustrating a method for cutting a structure. [Figure 12] FIG. 10 is a front view of a tilting structure according to a modified example of the first embodiment of the present disclosure. [Figure 13] FIG. 10 is a front view of a tilting structure according to a second embodiment of the present disclosure. [Figure 14] FIG. 10 is a front view of a tilting structure according to a second embodiment of the present disclosure. [Figure 15] FIG. 10 is a front view of a tilting structure according to a third embodiment of the present disclosure. [Figure 16] FIG. 10 is a front view of a tilting structure according to a third embodiment of the present disclosure. [Figure 17] FIG. 10 is a front view of a tilting structure according to a third embodiment of the present disclosure. [Figure 18] FIG. 11 is a front view of a tilting structure according to a modified example of the third embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0011] As shown in FIG. 1, the tilting method and tilting structure according to each embodiment of the present disclosure are a method and structure used when dismantling a structure 200. Note that "dismantling" here does not mean the work of dismantling the structure 200 itself, but rather the work of separating the structure 200 from the ground 401 until it is in a state where it can be moved from its installed location. Furthermore, the term "ground 401" is a term that includes not only land but also the bottom of water such as the bottom of the sea or lake. In the following embodiments, unless the type of ground 401 is specifically mentioned, the ground 401 is assumed to include land and the bottom of water.

[0012] The structure 200 is a floor-mounted structure that extends vertically upward from the ground 401 when installed on the ground 401 (that is, has a longitudinal direction in the vertical direction). Examples of the structure 200 include a meteorological observation tower, a leg structure of a marine facility, a lighthouse, a power transmission tower, a wind turbine for generating electricity, and the like.

[0013] The structure 200 has a foundation 210 and a structure body 220 . In the structure 200, the boundary between the foundation 210 and the structure main body 220 does not need to be clearly distinguished.

[0014] The foundation 210 extends vertically, and its lower portion is driven into the ground 401 . The foundation 210 may be of the monopile type shown in the figure, or may be of the jacket type, tripod type, tripile type, etc., and the specific form of the structure is not limited as long as it is of the bottom-mounted type.

[0015] The structure body 220 is provided on top of the foundation 210 in the vertical direction. When the ground 401 is the bottom of the water, that is, when the structure 200 is a structure on water, the structure main body 220 has a portion including its upper end that appears above the water surface 403 . The structure main body 220 is the part that performs the substantial function of the structure 200. Since the structure main body 220 includes the equipment necessary to perform that function, the weight of the structure main body 220 is often heavier than the weight of the foundation 210.

[0016] Hereinafter, the tilting method of the structure 200 and the tilting structure will be specifically described using several embodiments as examples.

[0017] [First embodiment] A method for tilting a structure and a tilting structure according to a first embodiment of the present disclosure will be described with reference to FIGS. 2 to 12. FIG.

[0018] In the method for tilting a structure of this embodiment, the structure 200 is tilted by tilting a tilting structure 310 configured by attaching a resistance member 110 to the structure 200.

[0019] As shown in FIGS. 2 and 3, 4 and 5, and 6 and 7, the tilting structure 310 includes a structure 200 and a resistance member 110.

[0020] The structure 200 is, for example, an above-water structure erected from the bottom of the water, and the base 210 and the lower part of the structure main body 220 are located underwater 402. The upper part of the structure main body 220 is located in the air 404. For example, if the structure 200 is a land structure erected on land, the entire foundation 210 and the structure body 220 will be in the air 404 .

[0021] The resistance member 110 is a member attached to the structure 200 (for example, the side surface of the structure main body 220), and is a member that receives a fluid force as resistance from the fluid surrounding the structure 200. The fluid surrounding the structure 200 is water in the water 402 (see FIGS. 2 and 3) or air in the air 404 (see FIGS. 4 and 5) or both water and air if the structure 200 is an on-water structure. Also, the fluid surrounding the structure 200 is air in the air 404 if the structure 200 is a land structure.

[0022] The resistance member 110 is preferably one that is lightweight yet has a large area that receives resistance from the fluid, and that can efficiently receive resistance from the fluid, and examples thereof include a sail, a board, and an impeller.

[0023] [Example when the resistance member is a sail] The structure of a specific example in which the resistance member 110 is a sail will be described below. As shown in FIGS. 2 and 3 and 4 and 5, the resistance member 110 has a strut 111 and a sail body 112.

[0024] The support pillar 111 is a long rod-shaped part that is attached to the side of the structure main body 220 and protrudes horizontally. The support columns 111 are attached, for example, one at a time, at positions 180 degrees symmetrical with respect to the structure body 220. This allows the structure 200 to receive a fluid force uniformly in the horizontal direction (the left-right direction in FIG. 2) via the resistance members 110.

[0025] The sail body 112 is a membrane-like part stretched between the strut 111 and the structural body 220. The sail body 112 is the part of the resistance member 110 that receives most of the resistance from the fluid. The sail body 112 is stretched by being connected to three points, for example, the tip of the pole 111, the base of the pole 111, and the side of the structure body 220. In this case, the sail body 112 has a substantially triangular shape.

[0026] The configuration of the support 111 and sail body 112 of the resistance member 110 is not limited to the above specific example, as long as the sail body 112 is stretched so that it can receive fluid force from the water in the water 402 and / or the air in the air 404.

[0027] [Example when the resistance member is an impeller] The structure of a specific example in which the resistance member 110 is an impeller will be described below. As shown in FIGS. 6 and 7, the resistance member 110 includes an impeller body 116 and a duct 117.

[0028] The impeller body 116 is housed inside a cylindrical duct 117 and is rotatable around a rotation axis Xf extending along the axis Xd of the duct 117.

[0029] The impeller body 116 may be driven by a driving unit (not shown) such as an electric motor, or may simply be installed so as to be freely rotatable. In the former case, the tilting speed can be adjusted efficiently by controlling the rotation speed of the impeller body 116. In the latter case, the impeller body 116 rotates due to fluid force, generating resistance.

[0030] Ducts 117 accommodating impeller bodies 116 are fixed and connected to structure body 220 by supports 118, and are attached, for example, one at a time, at positions 180 degrees symmetrical with structure body 220.

[0031] In the resistance member 110 configured as described above, the resistance member 110 may be configured to be rotatable and movable relative to the structure 200, for example, so that the direction in which the sail or impeller receives fluid force from the water in the water 402 and / or the air in the air 404 can be changed.

[0032] Resistance member 110 may be attached when structure 200 is constructed, or may be attached immediately before dismantling structure 200. Support column 111 or support column 118 may be attached when structure 200 is constructed, and sail body 112 or impeller body 116 and duct 117 may be attached immediately before dismantling.

[0033] In the tilting structure 310 configured as described above, the tilting structure 310 is tilted by cutting all or part of the structure 200 at the cutting surface 230 set near the base of the structure 200. At this time, the resistance member 110 receives a fluid force as resistance from the water in the water 402 and / or the air in the air 404, and the tilting speed of the tilting structure 310 is reduced.

[0034] When a sail is used as the resistance member 110, the tilting speed can be adjusted by, for example, increasing or decreasing the area of ​​the surface of the sail body 112 that receives resistance. Furthermore, when an impeller is used as the resistance member 110, the tilting speed can be adjusted efficiently by controlling the rotation speed of the impeller, for example.

[0035] When cutting the structure 200, the tilting direction of the tilting structure 310 can be adjusted by going through the same process as for felling a tree, as shown in FIGS.

[0036] Specifically, first, as shown in FIGS. 8 and 9, a socket 200a is formed in the side surface of the structure 200. The socket 200a is formed in the direction in which the tilting structure 310 is desired to be tilted.

[0037] Next, as shown in Figure 10, a follower cut 200b is formed horizontally from the side of the structure 200 opposite the socket 200a toward the socket 200a, leaving a ridge 200c to serve as a fulcrum for tilting.

[0038] 10 and 11, a trigger load is applied so that the tilting structure 310 tilts in a direction that closes the socket 200a. This allows the tilting structure 310 to tilt in a desired direction. An example of the means for applying the load that serves as the trigger is the winch 130 (wire 132) described in the third embodiment.

[0039] According to this embodiment, the following effects are achieved. Since the method includes an installation process of attaching the resistance member 110 to the structure 200 and a tilting process of tilting the structure 200 (i.e., the tilting structure 310) to which the resistance member 110 is attached, the tilting speed of the structure 200 can be reduced by the fluid force received by the resistance member 110 when tilting the structure 200. This allows the structure 200 to be tilted safely, and also reduces the impact when the structure 200 hits the water surface 403 or the ground.

[0040] [Variations] As shown in FIG. 12, when the structure 200 is, for example, a wind turbine, a sail body 112 may be stretched between the blades. In this case, the sail body 112 is tensioned by being connected to three points, for example, the tip of the blade, the tip of the adjacent blade, and the hub.

[0041] [Second embodiment] A structure tilting method and a tilting structure according to a second embodiment of the present disclosure will be described with reference to FIGS. 13 and 14. FIG. The tilting structure 320 according to this embodiment differs from the tilting structure 310 according to the first embodiment in that it does not have the resistance member 110 but has a floating member 120. Therefore, the same components are denoted by the same reference numerals and their description will be omitted.

[0042] In the method for tilting a structure of this embodiment, the structure 200 is tilted by tilting a tilting structure 320 configured by attaching a floating member 120 to the structure 200.

[0043] As shown in FIGS. 13 and 14, the tilting structure 320 includes a structure 200 and a floating member 120. In this embodiment, the structure 200 is an above-water structure erected from the bottom of the water, such as the seabed.

[0044] The floating member 120 is a member attached to the structure 200 (for example, the side surface of the structure main body 220), and receives buoyancy from the water surrounding the structure 200. The buoyancy provided by the floating member 120 supports the structure 200 separated from the bottom of the water. In other words, the specifications of the floating member 120 are designed so that a buoyancy is generated that supports the structure 200 separated from the bottom of the water.

[0045] The floating member 120 may be provided around the entire periphery of the structure 200 or around a portion of the periphery. The floating member 120 is configured by filling the inside of a bag-like object made of a material such as nylon or rubber with gas.

[0046] The floating members 120 may be installed during construction of the structure 200 or may be installed just prior to dismantling the structure 200.

[0047] In the tilting structure 320 configured as described above, the structure 200 is cut in whole or in part at the cutting plane 230 set near the base of the structure 200. At this time, the floating member 120 receives buoyancy from the water, which prevents the tilting structure 310 from collapsing or tilting due to its own weight. In other words, even if the structure 200 is separated from the water bottom, the structure 200 can stand on its own as a floating object.

[0048] Once the structure 200 has been separated from the bottom of the water, the tilting structure 320 is tilted by a predetermined means. At this time, the structure 200 tries to maintain its self-supporting state by the floating member 120, so when tilting the structure 200, the tilting speed of the structure 200 can be adjusted. An example of the means for tilting the tilting structure 320 is the winch 130 (wire 132) described in the third embodiment.

[0049] According to this embodiment, the following effects are achieved. The method includes an installation process for attaching the floating member 120 to the structure 200, and a tilting process for tilting the structure 200 (i.e., the tilting structure 320) to which the floating member 120 is attached, so that the structure 200 can stand on its own as a floating object even if it is detached from the bottom of the water. This makes it possible to adjust the tilting speed of the structure 200 when tilting the structure 200, thereby enabling safe tilting of the structure 200. Also, it is possible to reduce the impact when the structure 200 hits the water surface 403.

[0050] [Third embodiment] A structure tilting method and a tilting structure according to a third embodiment of the present disclosure will be described with reference to FIGS. 15 to 17. FIG. The tilting structure 330 according to this embodiment differs from the tilting structure 310 according to the first embodiment in that it does not have the resistance member 110 but has the pulling member 132. Therefore, the same components are denoted by the same reference numerals and the description thereof will be omitted.

[0051] The method for tilting a structure of this embodiment is a method for tilting a tilting structure 330 in which a pulling member 132 is connected to a structure 200. In the method for tilting a structure of this embodiment, the pulling member 132 is pulled to tilt the structure 200.

[0052] As shown in FIG. 15, the tilting structure 330 includes the structure 200 and the traction member 132 .

[0053] The pulling member 132 is, for example, a wire 132 provided in the winch 130 . The winch 130 has a winch body 131 in addition to a wire 132 . The winch body 131 is a part that pulls out / winds the wire 132. One end of the wire 132 is connected to the winch body 131, and the other end is connected to the upper part of the structure 200 (specifically, the upper part of the structure body 220).

[0054] The winch 130 may be installed on the ship 500 as shown in Fig. 15, or may be installed on the bottom of the water as shown in Fig. 16. Also, as shown in Fig. 17, a winch 130 installed on the ship 500 and a winch 130 installed on the bottom of the water may be combined.

[0055] In either case, multiple winches 130 are installed. In the case of Fig. 15, three winches 130 (winch 130a, winch 130b, and winch 130c) are installed.

[0056] The wire 132 of the winch 130 is preferably attached just prior to dismantling the structure 200 .

[0057] In the tilting structure 330 configured as described above, the structure 200 is cut in whole or in part at the cutting plane 230 set near the base of the structure 200 to tilt the tilting structure 330.

[0058] Of the winches 130, one winch 130 (e.g., winch 130a) pulls the tilting structure 330 in a predetermined direction (the direction in which it is desired to tilt), and the remaining two winches 130 (e.g., winch 130b and winch 130c) adjust the tilting speed by balancing with the pulling force of winch 130a. This allows the tilting structure 330 to be tilted in a desired direction while adjusting the tilting speed.

[0059] It should be noted that when cutting the structure 200, the same steps as those for felling a tree as shown in Figures 8 to 11 may be performed. In this case, the pulling force of the winch 130a serves as a trigger for tilting the tilting structure 330.

[0060] According to this embodiment, the following effects are achieved. The structure 200 is tilted by pulling the upper part of the structure 200, so the tilting speed and tilting direction can be controlled by the pulling direction and pulling force.

[0061] [Variations] For example, instead of the wires 132 of the winches 130b and 130c shown in Fig. 15, a connecting member 141 that connects a structure 200 (first structure 200) to another structure 200 (second structure 200) may be installed as shown in Fig. 18. The connecting member 141 is, for example, a wire 141.

[0062] As a result, by tilting the tilting structure 330 including the first structure 200, it is possible to tilt the tilting structure 330 including the second structure 200 in a chain reaction. In other words, the pulling force of the wire 141 generated by the tilting of the tilting structure 330 can be used as a load that serves as a trigger for tilting the other tilting structures 330. Furthermore, the tilting structure 330 and the other tilting structures 330 support each other via the wires 141, which prevents them from collapsing immediately after being detached from the bottom of the water.

[0063] The structure tilting method and tilting structure according to each embodiment described above can be understood, for example, as follows. That is, the method for tilting a structure (200) according to one embodiment of the present disclosure is a method for tilting a fixed structure extending upward from the ground (401), and includes an installation step of attaching a resistance member (110) to the structure that receives a fluid force from the fluid surrounding the structure, and a tilting step of tilting the structure to which the resistance member is attached.

[0064] The method for tilting a structure according to this aspect includes an installation step of attaching a resistance member to the structure, which receives a fluid force from the fluid surrounding the structure, and a tilting step of tilting the structure to which the resistance member is attached. Therefore, when tilting the structure, the fluid force received by the resistance member can reduce the tilting speed of the structure. This allows the structure to be tilted safely. It also reduces the impact when the structure hits the water surface or the ground. The term "ground" used here includes not only land but also the bottom of water such as the bottom of the sea or lake, etc. In other words, the structure targeted in this embodiment may be one installed on land or one installed on the bottom of water such as the bottom of the sea. The resistance member is preferably one that is lightweight yet has a large area that receives resistance from the fluid and that can efficiently receive resistance from the fluid. Examples of resistance members include sails, boards, and impellers.

[0065] In addition, in a method for tilting a structure according to one aspect of the present disclosure, the structure is an above-water structure extending from the bottom of the water, and the resistance member is located underwater and / or in the air.

[0066] According to the method for tilting a structure of this embodiment, the structure is an above-water structure extending from the bottom of the water, and the resistance member is located underwater and / or in the air, so that it can receive fluid force from the water in the water and / or the air in the air.

[0067] Furthermore, a method for tilting a structure according to one aspect of the present disclosure is a method for tilting a bottom-mounted structure extending upward from the bottom of the water, and includes an installation step of attaching a floating member (120) that receives buoyancy from the water to the structure, and a tilting step of tilting the structure to which the floating member is attached.

[0068] The method for tilting a structure according to this aspect includes an installation step of attaching a floating member that receives buoyancy from the water to the structure, and a tilting step of tilting the structure with the floating member attached. Therefore, the buoyancy of the floating member prevents the structure from collapsing immediately after being detached from the water bottom, allowing the structure to stand on its own as a floating object. This makes it possible to adjust the tilting speed when tilting the structure. This allows the structure to be tilted safely. It also reduces the impact when the structure hits the water surface.

[0069] In addition, in the method for tilting a structure according to one aspect of the present disclosure, the tilting step tilts the structure by pulling an upper portion of the structure.

[0070] According to the method for tilting a structure of this embodiment, in the tilting process, the structure is tilted by pulling the upper part of the structure, so that the tilting speed and tilting direction can be controlled by the pulling direction and pulling force. Preferably, the traction is performed from multiple directions.

[0071] Furthermore, in a method for tilting a structure according to one embodiment of the present disclosure, the structure has a first structure and a second structure installed at a distance from each other, and includes a connecting step of connecting the first structure and the second structure before the tilting step, and in the tilting step, tilting the first structure causes the second structure to tilt in a chain reaction.

[0072] According to the method for tilting a structure of this embodiment, the structure has a first structure and a second structure installed at a distance from each other, and includes a connecting step of connecting the first structure and the second structure before the tilting step.In the tilting step, the first structure is tilted to tilt the second structure in a chain reaction, so that by tilting one structure out of multiple structures, the other structures can be tilted in a chain reaction. Furthermore, since the first structure and the second structure support each other, they can be prevented from collapsing immediately after being separated from the bottom of the water.

[0073] Furthermore, a method for tilting a structure according to one aspect of the present disclosure is a method for tilting a bottom-mounted structure extending upward from the bottom of the water, and includes an installation step of attaching a towing member (132) for towing the structure to the top of the structure, and a tilting step of tilting the structure by towing the structure to which the towing member is attached.

[0074] In addition, a method for tilting a structure according to one embodiment of the present disclosure includes, before the tilting step, a cutting step of forming a cut portion that separates a ground-side portion of the structure from an upper portion of the structure.

[0075] In addition, a method for tilting a structure according to one embodiment of the present disclosure includes, before the tilting step, a cutting step of partially forming a cut portion that separates a portion of the structure on the ground side from a portion of the structure above it.

[0076] In addition, a tilting structure (310) according to one embodiment of the present disclosure comprises a bottom-mounted structure extending upward from the ground, and a resistance member attached to the structure and receiving a fluid force from the fluid surrounding the structure.

[0077] In addition, a tilting structure (320) according to one embodiment of the present disclosure comprises a bottom-mounted structure extending upward from the bottom of the water, and a floating member attached to the structure and receiving buoyancy from the water.

[0078] In addition, a tilting structure (330) according to one embodiment of the present disclosure comprises a floor-mounted structure extending upward from the ground, and a towing member (132) attached to the top of the structure and towing the structure. [Explanation of symbols]

[0079] 110 Resistance member 111 Post 112 Sail body 116 Impeller body 117 Duct 118 Post 120 Floating member 130 Winch 131 Winch body 132 Wire (traction member) 141 Wire (connecting member) 200 Structures 200a Underbite 200b Chase 200c Crane 210 Basics 220 Structure body 230 Cutting surface 310,320,330 Tilting structure 401 Ground 402 Underwater 403 Water surface 404 Air 500 ships

Claims

1. A method for tilting a structure that tilts a bottom-mounted structure that extends upward from the ground, comprising: an installation step of attaching a resistance member to the structure, the resistance member receiving a fluid force from a fluid surrounding the structure; a tilting step of tilting the structure to which the resistance member is attached; Including, A method for tilting a structure in which the resistance member is a sail or an impeller (excluding wind turbine blades for power generation).

2. A tilting speed adjusting step of changing the fluid force that the resistance member receives from the fluid in order to adjust the tilting speed of the structure, In the tilting speed adjusting step, The tilting speed is adjusted by increasing or decreasing the area of ​​the surface that receives resistance of the sail, or The tilting speed is adjusted by controlling the rotation speed of the impeller. The method for tilting a structure according to claim 1.

3. The structure is an above-water structure extending from the bottom of the water, 3. The method for tilting a structure according to claim 1 or 2, wherein the resistance member is located in water and / or in air.

4. 4. The method for tilting a structure according to claim 1, wherein the tilting step tilts the structure by pulling an upper portion of the structure.

5. A method for tilting a structure as described in any one of claims 1 to 4, which includes a cutting step, prior to the tilting step, of forming a cut portion that separates the portion of the structure on the ground side from the portion of the structure above it.

6. A method for tilting a structure as described in any one of claims 1 to 4, which includes a cutting step, prior to the tilting step, of partially forming a cut section that separates the portion of the structure on the ground side from the portion of the structure above it.

7. a bottom-mounted structure extending upward from the ground; a resistance member attached to the structure and receiving a fluid force from a fluid surrounding the structure; Equipped with The tilting structure wherein the resistance member is a sail or an impeller (excluding wind turbine blades for power generation).

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