Wind power tower tube self-locking flange plate connecting structure and wind power tower tube mounting method

Abstract

The invention discloses a wind power tower tube self-locking type flange plate connecting structure and a wind power tower tube mounting method.The wind power tower tube self-locking type flange plate connecting structure comprises a first cylinder and a second cylinder which are the same in height, and the cylindrical surface of the first cylinder is provided with a first spiral in a hollowed-out mode; the cylindrical surface of the second cylinder is hollowed to form a second helix, the helix axes of the first helix and the second helix coincide with the central axis of the cylinder, and the helix angles of the first helix and the second helix are different so as to realize helix matching and form a helix pair; when the bottom of the first cylinder is arranged at the top of the second cylinder, the first cylinder rotates downwards in the spiral direction under the action of gravity, and along with rotation, the first cylinder and the second cylinder are in spiral self-locking engagement gradually, and finally a complete cylinder is formed. Bolt connection is abandoned, gravity self-locking can be achieved, and the installation efficiency and long-term reliability of the wind power tower drum are fundamentally improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of wind power generation, and particularly relates to a wind power tower drum self-locking flange plate connecting structure and a wind power tower drum installation method. BACKGROUND

[0002] In the field of wind power generation, the wind power tower drum is an indispensable support structure of a wind turbine generator system. Since the wind power tower drum usually has a large height and size, in order to facilitate transportation and installation, a segmented manufacturing and then on-site connecting and assembling mode is generally adopted.

[0003] At present, the traditional flange plate bolt connecting structure widely used in the industry is the mainstream way for segmented connection of the wind power tower drum. The specific operation process of this structure is that the flange plates of two tower drums are first butt-jointed, and then high-strength bolt groups are used to fasten and connect the flange plates. However, this connecting mode has defects: first, the installation efficiency of the traditional flange plate bolt connecting structure is extremely low. When connecting operation is performed, dozens or even hundreds of bolt hole positions on the flange plates need to be aligned. In the actual offshore high-altitude operation environment, the situation is more complex and harsh. For example, the hoisting platform will sway due to sea waves and other factors, and will also be disturbed by strong winds. Under such conditions, it is difficult to accurately insert the bolts into the hole positions and achieve synchronous pre-tightening, and the whole process is time-consuming. Second, the maintenance cost of this connecting structure is high. During the operation of the wind power tower drum, the bolts will be subjected to the action of alternating loads for a long time. Under the action of this continuous stress, the bolts are prone to stress relaxation, resulting in a decrease in pre-tightening force and a decrease in connection reliability; at the same time, the bolts may also be broken due to corrosion. In order to ensure the safe operation of the wind power tower drum, it is necessary to regularly perform shutdown tensioning or replacement operation on the bolts. Finally, the traditional flange plate bolt connecting structure has structural reliability risks. During the pre-tightening of the bolts, it is difficult to ensure that the pre-tightening force of each bolt is completely uniform. Uneven pre-tightening force will cause local stress concentration on the flange surface, and under the long-term action of extreme wind load, these stress concentration positions are prone to fatigue cracks, thereby affecting the structural safety of the wind power tower drum.

[0004] In summary, the traditional flange plate bolt connecting structure has many problems in installation efficiency, maintenance cost and structural reliability, and has been unable to meet the needs of the rapid development of the wind power industry. Therefore, it is of great practical significance to develop an integrated flange plate structure that discards bolt connection and can realize gravity self-locking, which is expected to fundamentally improve the installation efficiency and long-term reliability of the wind power tower drum. SUMMARY

[0005] In view of the problems in the prior art, the present application provides a wind power tower drum self-locking flange plate connecting structure and a wind power tower drum installation method, which discards bolt connection and can realize gravity self-locking, thereby fundamentally improving the installation efficiency and long-term reliability of the wind power tower drum.

[0006] To solve the above technical problems, the present application is realized by the following technical solutions:

[0007] According to a first aspect of the present application, a wind turbine tower self-locking flange connection structure is provided, comprising a first cylindrical tube and a second cylindrical tube with the same height, a first spiral is hollowed out on the cylindrical surface of the first cylindrical tube, a second spiral is hollowed out on the cylindrical surface of the second cylindrical tube, the spiral axes of the first spiral and the second spiral are both coincident with the central axis of the cylindrical tube, and the helix angles of the first spiral and the second spiral are different to realize spiral cooperation and form a helix pair.

[0008] When the bottom of the first cylindrical tube is placed on the top of the second cylindrical tube, under the action of gravity, the first cylindrical tube rotates downward along the spiral direction, and with the rotation, the first cylindrical tube and the second cylindrical tube gradually spiral self-locking engagement, and finally form a complete cylindrical tube.

[0009] In a possible implementation manner of the first aspect, the helix angle of the first spiral is 12°-14°, and the helix angle of the second spiral is 8°-10°.

[0010] In a possible implementation manner of the first aspect, the first cylindrical tube and the second cylindrical tube are made of 42CrMo4 alloy steel.

[0011] In a possible implementation manner of the first aspect, the first spiral and the second spiral are laser cladded with a tungsten carbide wear-resistant layer on the surface, and the thickness is 0.3mm-0.5mm.

[0012] In a possible implementation manner of the first aspect, a plurality of through top and bottom insertion holes are arranged on the first cylindrical tube and the second cylindrical tube in the circumferential direction.

[0013] When the first cylindrical tube and the second cylindrical tube are spiral engaged, the insertion holes of the two are one-to-one corresponding.

[0014] Further comprising an insertion piece inserted into the corresponding insertion hole.

[0015] In a possible implementation manner of the first aspect, the insertion piece is a plunger type hydraulic cylinder, and the single cylinder thrust is ≥50kN, which is configured to automatically drop into the insertion hole after the two parts of the cylindrical tube are engaged.

[0016] In a possible implementation manner of the first aspect, a stress sensor is embedded in the first spiral and the second spiral, which is used to monitor the stress state of the structure after engagement.

[0017] In a possible implementation manner of the first aspect, a sealing assembly is arranged at the spiral locking joint, and the sealing assembly comprises a primary sealing layer, a secondary sealing layer and an emergency sealing layer in sequence.

[0018] In a possible implementation manner of the first aspect, the primary sealing layer is a fluororubber O-shaped ring, the secondary sealing layer is a graphite winding gasket, and the emergency sealing layer is a water-swelling resin microcapsule layer.

[0019] According to a second aspect of the present application, a wind power tower installation method is provided, which adopts the wind power tower self-locking flange connection structure, and comprises the following steps:

[0020] Welding a section of tower cylinder to the top of the first cylindrical cylinder and welding another section of tower cylinder to the bottom of the second cylindrical cylinder;

[0021] Hoisting the first cylindrical cylinder to the top of the second cylindrical cylinder;

[0022] Under the action of gravity, the first cylindrical cylinder rotates in a spiral direction downward, and with the rotation, the first cylindrical cylinder gradually spirally self-locks and engages with the second cylindrical cylinder, and finally forms a complete cylindrical cylinder to realize the connection of the two sections of tower cylinders.

[0023] Compared with the prior art, the present application has at least the following beneficial effects:

[0024] The wind power tower self-locking flange connection structure provided by the present application simplifies the installation process, shortens the installation time and effectively improves the installation efficiency.

[0025] In the traditional flange bolt connection structure, the bolts are subjected to alternating loads during the operation of the wind turbine tower, and stress relaxation occurs, which leads to a decrease in pre-tightening force and reduces the connection reliability, and the bolts may also be broken due to corrosion. In order to ensure the safe operation of the wind turbine tower, the bolts need to be regularly tensioned or replaced during shutdown, which is costly. The self-locking flange connection structure of the present application discards the bolt connection mode, and there is no problem of stress relaxation and corrosion breakage of the bolts, which fundamentally avoids the maintenance requirements caused by the problems of the bolts. Therefore, it is not necessary to regularly tension or replace the bolts, which greatly reduces the maintenance cost of the wind turbine tower.

[0026] In the traditional flange bolt connection structure, it is difficult to ensure that the pre-tightening force of each bolt is completely uniform during the pre-tightening process of the bolts, and uneven pre-tightening force will lead to local stress concentration on the flange surface. Under the long-term action of extreme wind load, these stress concentration positions are prone to cause fatigue cracks, which affects the structural safety of the wind turbine tower. The self-locking flange connection structure of the present application forms a screw pair by the cooperation of the first screw and the second screw with different helix angles on the first cylindrical barrel and the second cylindrical barrel, and realizes screw self-locking engagement under the action of gravity. This connection mode can make the two cylindrical barrels bear force uniformly, and avoids the problem of fatigue cracks caused by local stress concentration, which structurally ensures the reliable and stable connection.

[0027] In summary, the self-locking flange connection structure of the wind turbine tower and the wind turbine tower installation method of the present application effectively solve the problems of low installation efficiency, high maintenance cost and poor structural reliability of the traditional flange bolt connection structure.

[0028] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the following preferred embodiments are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the specific embodiments of the present application, the following will briefly introduce the drawings needed to be used in the description of the specific embodiments. Obviously, the drawings described below are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creating any creative labor on the basis of these drawings.

[0030] Figure 1 It is a schematic view of a self-locking flange connection structure of a wind turbine tower (without cooperating with a plug-in part).

[0031] Figure 2 It is a schematic view of a self-locking flange connection structure of a wind turbine tower (cooperating with a plug-in part, when the plug-in part is not completely inserted).

[0032] In the drawings: 1, first cylindrical barrel; 2, second cylindrical barrel; 3, plug-in hole; 4, plug-in part. DETAILED DESCRIPTION

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0034] Combine Figure 1 and Figure 2 As shown, in this embodiment, a self-locking flange connection structure of a wind turbine tower and an installation method thereof are described in detail. This structure abandons the traditional bolt connection method and realizes gravity self-locking, thereby improving the installation efficiency and long-term reliability of the wind turbine tower.

[0035] The present invention provides a self-locking flange connection structure for a wind turbine tower, primarily comprising a first cylindrical tube 1 and a second cylindrical tube 2 of equal height. A first spiral is hollowed out on the surface of the first cylindrical tube 1, while a second spiral is hollowed out on the surface of the second cylindrical tube 2. The spiral axes of the first and second spirals coincide with the central axis of the cylindrical tubes, and the first and second spirals have different pitch angles to achieve spiral coordination, forming a spiral pair.

[0036] The first cylinder 1 is hoisted directly above the second cylinder 2, then slowly lowered so that its bottom gradually approaches the top of the second cylinder 2. Once the bottom of the first cylinder 1 contacts the top of the second cylinder 2, the first cylinder 1, under its own gravity, begins to rotate downward along a pre-designed spiral direction. As the rotation continues, the first spiral on the first cylinder 1 and the second spiral on the second cylinder 2 gradually interlock. Due to the difference in the spiral pitch angle, after a certain degree of rotation, the two cylinders automatically self-lock and eventually tightly connect together to form a complete cylinder.

[0037] In this embodiment, the helix angle of the first helix is ​​set to 12° to 14°, and the helix angle of the second helix is ​​set to 8° to 10°. For example, the helix angle of the first helix is ​​set to 12°, and the helix angle of the second helix is ​​set to 8°. Such helix angle settings enable the first cylindrical barrel 1 to rotate downward in a spiral direction under the action of gravity when the bottom of the first cylindrical barrel 1 is placed on the top of the second cylindrical barrel 2. As the rotation proceeds, the first cylindrical barrel 1 and the second cylindrical barrel 2 gradually engage in a spiral self-locking manner, ultimately forming a complete cylindrical barrel.

[0038] In this embodiment, the first and second cylindrical tubes 1 and 2 are constructed from 42CrMo4 alloy steel, a material with excellent mechanical properties and corrosion resistance, meeting the requirements for wind turbine towers in complex environments. Furthermore, a wear-resistant tungsten carbide layer with a thickness of 0.3mm to 0.5mm is laser-clad on the surfaces of the first and second spirals, effectively improving the wear resistance of the spiral surfaces and extending the service life of the connection structure. For example, the thickness is 0.3mm.

[0039] In one possible implementation, in order to further enhance the stability of the connection structure, a plurality of plug holes 3 penetrating the top and bottom surfaces are provided on both the first cylindrical barrel 1 and the second cylindrical barrel 2 along the circumferential direction. When the first cylindrical barrel 1 and the second cylindrical barrel 2 are screwed together, the plug holes 3 of the two correspond one to one. It also includes a connector 4 inserted into the corresponding plug hole 3. In this embodiment, the connector 4 is a plunger-type hydraulic cylinder with a single-cylinder thrust of ≥50kN. It is configured to automatically lower into the plug hole 3 after the two parts of the cylindrical barrel are engaged, providing additional fixing force for the connection structure. Exemplarily, 8 plug holes 3 penetrating the top and bottom surfaces are provided on both the first cylindrical barrel 1 and the second cylindrical barrel 2 along the circumferential direction.

[0040] In one possible implementation, stress sensors 5 are embedded in the first spiral and the second spiral to monitor the stress state of the structure after occlusion, so as to promptly detect potential safety hazards.

[0041] In one embodiment, a sealing assembly is provided at the spiral joint. The sealing assembly comprises, in sequence, a primary sealing layer, a secondary sealing layer, and an emergency sealing layer. The primary sealing layer utilizes a fluororubber O-ring, the secondary sealing layer utilizes a spiral wound graphite gasket, and the emergency sealing layer utilizes a water-swellable resin microcapsule layer. This multi-layer sealing structure effectively prevents intrusion of foreign matter and ensures the sealing of the connection structure.

[0042] In one implementation, a wireless energy transmission unit is further included to supply energy to the connector and / or the stress sensor based on magnetic resonance coupling technology, with a transmission efficiency of >85%, thereby ensuring the normal operation of the connector and the stress sensor.

[0043] In one possible implementation, a method for installing a wind turbine tower using the aforementioned self-locking flange connection structure for the wind turbine tower is as follows:

[0044] First, one tower section is welded to the top of the first cylindrical tube 1, and the other tower section is welded to the bottom of the second cylindrical tube 2. During the hoisting process, in order to achieve precise docking, guide pins (taper 1:50) are used to achieve rough positioning (error <±3mm).

[0045] Then, hoist the first cylindrical barrel 1 to the top of the second cylindrical barrel 2. Under the action of gravity, the first cylindrical barrel 1 rotates downward in a spiral direction, and as the rotation proceeds, the first cylindrical barrel 1 gradually spirally self-locks and engages with the second cylindrical barrel 2, and finally forms a complete cylindrical barrel, realizing the connection of the two sections of the tower barrel.

[0046] Through the above specific embodiments, the wind power tower barrel self-locking flange connection structure and installation method effectively solve the problems of traditional flange bolt connection structures in terms of installation efficiency, maintenance cost and structural reliability, and provide a more optimal solution for the development of the wind power industry.

[0047] In combination with Table 1, compared with the traditional bolt flange connection method, the self-locking flange connection structure has significant advantages. Taking a flange with a diameter of 5 meters as an example:

[0048] Table 1 Comparison of the present application and traditional bolt flange connection

[0049]

[0050]

[0051] In terms of connection time, the traditional bolt flange connection requires 6-8 hours (32 people team), while the self-locking flange connection of the present application only needs 1.5 hours (automatic operation), greatly shortening the installation time and improving the installation efficiency.

[0052] In terms of the number of bolts, the traditional bolt flange connection requires 128 M36 bolts, while the self-locking flange connection of the present application only needs 8 hydraulic drive units, reducing the use of parts and simplifying the installation process.

[0053] In terms of interface pressure uniformity, the interface pressure uniformity of the traditional bolt flange connection is ±15%, while the interface pressure uniformity of the self-locking flange connection of the present application is ±5%, improving the stability and reliability of the connection.

[0054] In terms of corrosion risk points: the traditional bolt flange connection has 128 bolt holes, which has a high corrosion risk, while the self-locking flange connection of the present application is a fully enclosed structure, effectively reducing the corrosion risk.

[0055] In terms of 50-year maintenance cost, the 50-year maintenance cost of the traditional bolt flange connection is about 12% of the cost of the tower barrel, and according to the predicted estimate, the 50-year maintenance cost of the self-locking flange connection of the present application is about 3% of the cost of the tower barrel, significantly reducing the maintenance cost.

[0056] In the description of the application, it is necessary to understand that the terms "upper", "lower", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application.

[0057] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified and limited.

[0058] In the present application, unless otherwise explicitly specified and limited, the terms "connected", "connected" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected or in communication with each other; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication or interaction relationship of two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0059] In the present application, unless otherwise explicitly specified and limited, the first feature "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "on", "above" and "above" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "under", "below" and "below" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0060] In the present application, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0061] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present application, and are used to illustrate the technical solutions of the present application, but are not intended to limit the present application. The protection scope of the present application is not limited thereto. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily think of changes to the technical solutions recorded in the foregoing embodiments, or make equivalent replacements to some of the technical features, within the technical scope disclosed by the present application. Such modifications, changes or replacements do not cause the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be covered within the protection scope of the present application.

Claims

1. A self-locking flange connection structure for a wind turbine tower, characterized in that: The invention comprises a first cylindrical tube (1) and a second cylindrical tube (2) of the same height, wherein a first spiral is hollowed out on the cylindrical surface of the first cylindrical tube (1), and a second spiral is hollowed out on the cylindrical surface of the second cylindrical tube (2), wherein the spiral axes of the first spiral and the second spiral both coincide with the central axis of the cylindrical tube, and the spiral angles of the first spiral and the second spiral are different so as to achieve spiral matching and form a spiral pair; When the bottom of the first cylindrical barrel (1) is placed on the top of the second cylindrical barrel (2), under the action of gravity, the first cylindrical barrel (1) rotates downward in a spiral direction. As the rotation proceeds, the first cylindrical barrel (1) and the second cylindrical barrel (2) gradually engage in a spiral self-locking manner, and finally form a complete cylindrical barrel.

2. A wind turbine tower self-locking flange connection structure according to claim 1, characterized in that: The helix angle of the first helix is ​​12° to 14°, and the helix angle of the second helix is ​​8° to 10°.

3. The self-locking flange connection structure of a wind turbine tower according to claim 1, characterized in that: The first cylindrical tube (1) and the second cylindrical tube (2) are made of 42CrMo4 alloy steel.

4. A wind turbine tower self-locking flange connection structure according to claim 1, characterized in that: The surfaces of the first spiral and the second spiral are laser-clad with a tungsten carbide wear-resistant layer with a thickness of 0.3 mm to 0.5 mm.

5. The self-locking flange connection structure of a wind turbine tower according to claim 1, characterized in that: The first cylindrical tube (1) and the second cylindrical tube (2) are both provided with a plurality of plug holes (3) penetrating the top and bottom surfaces along the circumferential direction; When the first cylindrical tube (1) and the second cylindrical tube (2) are screw-engaged, the plug holes (3) of the two tubes correspond one to one; It also includes a plug-in connector (4) plugged into the corresponding plug-in hole (3).

6. A wind turbine tower self-locking flange connection structure according to claim 1, characterized in that: The connector (4) is a plunger-type hydraulic cylinder with a single-cylinder thrust of ≥50 kN, and is configured to automatically drop into the connector hole (3) after the two cylindrical parts are engaged.

7. The self-locking flange connection structure of a wind turbine tower according to claim 1, characterized in that: Stress sensors (5) are embedded in the first spiral and the second spiral for monitoring the stress state of the structure after occlusion.

8. The self-locking flange connection structure of a wind turbine tower according to claim 1, characterized in that: A sealing component is provided at the spiral bite joint, and the sealing component comprises a primary sealing layer, a secondary sealing layer and an emergency sealing layer in sequence.

9. The self-locking flange connection structure of a wind turbine tower according to claim 1, characterized in that: The primary sealing layer adopts a fluororubber O-ring, the secondary sealing layer adopts a graphite spiral wound gasket, and the emergency sealing layer adopts a water-swellable resin microcapsule layer.

10. A method for installing a wind turbine tower, characterized in that: A wind turbine tower self-locking flange connection structure according to any one of claims 1 to 9 is adopted, comprising: Welding one section of the tower to the top of the first cylindrical tube (1), and welding another section of the tower to the bottom of the second cylindrical tube (2); Hoisting the first cylindrical tube (1) to the top of the second cylindrical tube (2); Under the action of gravity, the first cylindrical tube (1) rotates downward in a spiral direction. As the rotation proceeds, the first cylindrical tube (1) and the second cylindrical tube (2) gradually engage in a spiral self-locking manner, and finally form a complete cylindrical tube, thereby realizing the connection of the two sections of the tower tube.

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