Drawing force testing device and method for blade root embedded bolt sleeve of wind power blade

Abstract

The invention relates to a wind power blade root embedded bolt sleeve drawing force testing device and a testing method thereof. The wind power blade root embedded bolt sleeve drawing force testing device comprises a first connecting assembly, a second connecting assembly and a third connecting assembly, the first connecting assembly comprises an adapter and a first hinge piece, the first hinge piece comprises a first part and a second part which are hinged to each other, and the first part is connected with the adapter; the second connecting assembly comprises a bolt sleeve clamping piece and a second hinging piece, the second hinging piece comprises a third part and a fourth part which are hinged to each other, the third part is connected with the bolt sleeve clamping piece, and the bolt sleeve clamping piece is used for clamping a to-be-tested bolt sleeve; the pull rod comprises a first connecting end and a second connecting end which are oppositely arranged, the first hinge piece is arranged corresponding to the second hinge piece in the axial direction of the pull rod, the first connecting end is connected with the second component, and the second connecting end faces the second hinge piece and is used for being connected with a to-be-tested bolt sleeve.

Description

Technical Field

[0001] The present application relates to the field of wind power generation, and in particular to a wind power blade root embedded bolt sleeve pull-out force testing device and a testing method thereof. Background Art

[0002] In recent years, wind energy, as a large-scale commercial clean renewable energy, has received widespread attention from all countries. With the rapid development of my country's wind power industry, wind turbine blades are constantly increasing in size. Wind turbine blades are the core components of wind turbines to capture wind energy, and their operating status is directly related to the utilization efficiency of wind energy. Wind turbine blades are connected to the hub of the main generator through the embedded bolt sleeve at the blade root. The embedded bolt sleeve has an internal thread structure. The embedded bolt sleeve is connected to the hub of the main generator through bolts. The embedded bolt sleeve is one of the key load-bearing components of the embedded blade root structure. The strength of the blade root connector is an important mechanical indicator of large wind turbine blades. Therefore, how to perform pull-out force detection on the embedded bolt sleeve at the blade root of wind turbine blades to ensure the structural safety of large wind turbine blades has become a research focus. Summary of the invention

[0003] The present application provides a wind turbine blade root embedded bolt sleeve pull-out force testing device and testing method thereof, which can perform load testing on the bolt sleeve and ensure that the bolt sleeve bears axial load.

[0004] In a first aspect, an embodiment of the present application provides a pull-out force testing device for a pre-embedded bolt sleeve at the root of a wind turbine blade, comprising: a first connecting assembly comprising an adapter and a first hinge, the first hinge comprising a first component and a second component hinged to each other, the first component being connected to the adapter; a second connecting assembly comprising a bolt sleeve clamp and a second hinge, the second hinge comprising a third component and a fourth component hinged to each other, the third component being connected to the bolt sleeve clamp, the bolt sleeve clamp being used to clamp a bolt sleeve to be tested; a pull rod comprising a first connecting end and a second connecting end arranged opposite to each other, along the axial direction of the pull rod, the first hinge is arranged corresponding to the second hinge, the first connecting end is connected to the second component, the second connecting end is arranged facing the second hinge, and the second connecting end is used to connect the bolt sleeve to be tested.

[0005] The pull-out force testing device for the embedded bolt sleeve at the root of a wind turbine blade of the embodiment of the present application can perform load testing on the embedded bolt sleeve. The first connecting assembly, the second connecting assembly and the pull rod form a tooling for testing the bolt sleeve. When using the pull-out force testing device for the embedded bolt sleeve at the root of a wind turbine blade for testing, the bolt sleeve to be tested can be connected to the second connecting assembly, and the bolt sleeve can be connected to the pull rod. After completing the connection of the first connecting assembly, the second connecting assembly, the pull rod and the bolt sleeve, tensile forces in opposite directions can be applied to the fourth component of the adapter and the second hinge respectively, so as to apply a pull-out force to the pull rod and the bolt sleeve through the first connecting assembly and the second connecting assembly, so as to facilitate the judgment of whether the bolt sleeve can withstand the maximum pull-out force that meets the requirements, thereby judging whether the bolt sleeve meets the use requirements. The first connecting assembly and the second connecting assembly respectively include a first hinge and a second hinge, so that during the load loading process, the first hinge and the second hinge can adjust the relative position between the first component and the second component and the relative position between the third component and the fourth component in real time under the action of an external force, so as to ensure that the loading process is a tensile load, and to ensure that the pull rod and the bolt sleeve bear an axial load, so that the bending load borne on the pull rod and the bolt sleeve can be controlled within a range that meets the test requirements, thereby facilitating the reliability and accuracy of the test results.

[0006] In some achievable embodiments, the first component and the second component in the first hinge are spherically hinged.

[0007] In some achievable embodiments, one of the first component and the second component is provided with a spherical recess, and the other component is provided with a first spherical portion hingedly connected to the spherical recess.

[0008] In some achievable embodiments, the adapter seat includes a receiving groove, and along the axial direction of the pull rod, an opening of the receiving groove faces away from the second hinged component, and at least a portion of the first component is disposed in the receiving groove.

[0009] In some achievable embodiments, the first component includes a spherical recess, the second component includes a first spherical portion, the adapter includes a first through hole connected to the accommodating groove, the first component includes a second through hole connected to the spherical recess, the second component includes a third through hole passing through the first spherical portion, the pull rod is passed through the first through hole, the second through hole and the third through hole, and the first connecting end of the pull rod passes through the third through hole and is connected to the second component.

[0010] In some feasible embodiments, the adapter seat includes a chamber, and in a first direction, the chamber has an opening or the chamber has two opposite openings, the first direction is perpendicular to the axial direction of the first through hole, the accommodating groove is arranged on the inner wall of the adapter seat facing the chamber, and the first connecting end of the pull rod is located in the chamber.

[0011] In some feasible embodiments, the wind turbine blade root embedded bolt sleeve pull-out force testing device also includes an abutment member, the first connecting end of the pull rod is connected to the abutment member, along the axial direction of the pull rod, the second component is located between the abutment member and the first component, the second component abuts against the first component, and the abutment member abuts against the second component.

[0012] In some achievable embodiments, the third component and the fourth component of the second hinge are spherically hinged.

[0013] In some achievable embodiments, one of the third component and the fourth component includes a second spherical portion, and the other includes a spherical cavity hingedly connected to the second spherical portion.

[0014] In some feasible embodiments, the bolt sleeve clamp has a receiving hole for receiving the bolt sleeve to be tested, and the bolt sleeve clamp is used to clamp the bolt sleeve received in the receiving hole. Along the axial direction of the pull rod, the second connecting end of the pull rod is arranged corresponding to the receiving hole.

[0015] In some achievable embodiments, the bolt sleeve clamp includes at least two clamping plates, and along the circumference of the pull rod, the clamping plates are sequentially connected to form a receiving hole.

[0016] In some practicable embodiments, the inner wall of the clamping plate is provided with convex portions and concave portions, and the convex portions and concave portions are alternately arranged along the axial direction of the pull rod.

[0017] In some achievable embodiments, the second hinged member further includes a support rod, both ends of the support rod are respectively connected to the clamping plate, the second spherical portion is connected to the support rod, and at least a portion of the second spherical portion is located in the accommodating hole.

[0018] In some achievable embodiments, the wind turbine blade root embedded bolt sleeve pull-out force testing device further includes a strain sensor, which is disposed on the pull rod and is used to detect the axial load and bending load borne by the pull rod.

[0019] In some achievable embodiments, the strain sensor is a strain gauge, and two or more strain sensors are evenly spaced apart on the pull rod along the circumference of the pull rod.

[0020] In some achievable embodiments, the wind turbine blade root embedded bolt sleeve pull-out force testing device further includes a load loader, the adapter is connected to the load loader, and the fourth component of the second hinge is connected to the load loader.

[0021] In a second aspect, the present application provides a method for testing the pull-out force of a pre-embedded bolt sleeve at the root of a wind turbine blade, which comprises:

[0022] Provide adapter;

[0023] Providing a first hinged member, the first hinged member comprising a first component and a second component hinged to each other, connecting the first component to the adapter;

[0024] Provide bolt sleeve clamps;

[0025] Providing a second hinged member, the second hinged member comprising a third component and a fourth component hinged to each other, connecting the third component to the bolt sleeve clamping member;

[0026] Provide a bolt sleeve to be tested, and clamp the bolt sleeve using a bolt sleeve clamp;

[0027] providing a tie rod, connecting one end of the tie rod to the second component, and connecting the other end of the tie rod to the bolt sleeve;

[0028] Pulling forces in opposite directions are applied to the adapter and the fourth component respectively, so as to apply a pulling load to the pull rod and the bolt sleeve.

[0029] In some achievable embodiments, the method for testing the pull-out force of the pre-embedded bolt sleeve at the root of a wind turbine blade further includes: providing a strain sensor, wherein four strain sensors are evenly spaced on the pull rod along the circumference of the pull rod, and the strain sensor is used to detect the axial load and bending load borne by the pull rod.

[0030] Before testing the bolt sleeve loading, check the coaxiality of the tie rod:

[0031] Apply pull-out forces in opposite directions to the adapter and the fourth component, respectively, and obtain the strain values ​​of the four strain sensors, ε1, ε2, ε3, and ε4, respectively. When (ε1-ε3) / (ε1+ε3)=a, (ε2-ε4) / (ε2+ε4)=b, and (a ∧ 2+b ∧ 2) ∧ When 0.5<0.05, the pull rod meets the coaxiality requirement.

[0032] The pull-out force testing method for the embedded bolt sleeve at the root of a wind turbine blade in the embodiment of the present application can perform a load test on the embedded bolt sleeve. After completing the connection of the adapter, the first hinge, the bolt sleeve clamp, the second hinge, the pull rod and the bolt sleeve, a pull-out load can be applied to the pull rod and the bolt sleeve through the fourth component of the adapter and the second hinge, so as to facilitate the judgment of whether the bolt sleeve can withstand the maximum pull-out force that meets the requirements, thereby judging whether the bolt sleeve meets the use requirements. During the load loading process, the first hinge and the second hinge can adjust the relative position between the first component and the second component and the relative position between the third component and the fourth component in real time under the action of an external force, so as to ensure that the loading process is a tensile load, ensure that the pull rod and the bolt sleeve bear an axial load, so that the bending load borne on the pull rod and the bolt sleeve can be controlled within the range that meets the test requirements, thereby facilitating the reliability and accuracy of the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0034] Figure 1 A schematic diagram of the structure of a wind turbine generator set provided in some embodiments of the present application;

[0035] Figure 2 A schematic diagram of the structure of a blade provided in some embodiments of the present application;

[0036] Figure 3 A schematic diagram of the structure of a bolt sleeve provided in some embodiments of the present application;

[0037] Figure 4 A schematic diagram of the structure of a wind turbine blade root pre-embedded bolt sleeve pull-out force testing device provided in some embodiments of the present application;

[0038] Figure 5 A schematic diagram of the structure of a wind turbine blade root pre-embedded bolt sleeve pull-out force testing device provided in some embodiments of the present application;

[0039] Figure 6 A schematic diagram of a partial cross-sectional structure of a wind turbine blade root embedded bolt sleeve pull-out force testing device provided in some embodiments of the present application;

[0040] Figure 7 A schematic structural diagram of a first hinge provided in some embodiments of the present application;

[0041] Figure 8 A schematic diagram of the structure of a second hinge provided in some embodiments of the present application;

[0042] Fig. 9A schematic diagram of the structure of a wind turbine blade root pre-embedded bolt sleeve pull-out force testing device provided in some embodiments of the present application;

[0043] Fig.10 A schematic diagram of a partial cross-sectional structure of a first hinge provided in some embodiments of the present application;

[0044] Fig.11 A schematic diagram of the structure of an adapter provided in some embodiments of the present application;

[0045] Fig.12 A schematic diagram of a partial cross-sectional structure of a wind turbine blade root embedded bolt sleeve pull-out force testing device provided in some embodiments of the present application;

[0046] Fig.13 A schematic diagram of a partial cross-sectional structure of a second hinge provided in some embodiments of the present application;

[0047] Fig.14 A partial cross-sectional structural schematic diagram of a wind turbine blade root pre-embedded bolt sleeve pull-out force testing device and a bolt sleeve connection state provided in some embodiments of the present application;

[0048] Fig.15 A schematic diagram of the structure of a clamping plate provided in some embodiments of the present application;

[0049] Fig.16 A schematic diagram of a partial cross-sectional structure of a second connecting assembly provided in some embodiments of the present application;

[0050] Fig.17 A schematic diagram of the partial structure of a wind turbine blade root embedded bolt sleeve pull-out force testing device provided in some embodiments of the present application.

[0051] In the drawings, the drawings are not necessarily drawn to scale.

[0052] Description of reference numerals:

[0053] 100, wind turbine generator set; 110, tower; 120, nacelle; 130, wind rotor; 131, hub; 132, blade; 1321, main body; 1322, bolt sleeve; 1322a, boss; 1322b, groove; 10, wind turbine blade root embedded bolt sleeve pull-out force testing device; 20, first connecting assembly; 21, adapter; 211, receiving groove; 212, first through hole; 213, chamber; 214, first cylindrical portion; 215, second cylindrical portion; 22, first hinge; 221, first component; 221a, second through hole; 222, second component; 222a, third through hole ; 22a, spherical recess; 22b, first spherical portion; 30, second connecting assembly; 31, bolt sleeve clamp; 31a, accommodating hole; 311, clamping plate; 311a, convex portion; 311b, concave portion; 3111, arc plate; 3112, connecting plate; 32, second hinge; 321, third component; 322, fourth component; 32a, second spherical portion; 32b, spherical cavity; 32c, fourth through hole; 33, support rod; 40, pull rod; 41, first connecting end; 42, second connecting end; 50, abutment; 60, strain sensor; 70, load loader; X, axial direction; Y, first direction. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0055] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0056] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0057] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0058] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0059] The term "plurality" used in the present application refers to two or more (including two).

[0060] Figure 1 Schematic diagram showing the structure of a wind turbine. Figure 1 As shown, an embodiment of the present application provides a wind turbine generator set.

[0061] The wind turbine generator set includes a tower, a nacelle and a wind rotor. The nacelle is arranged at the top of the tower. The wind rotor includes a hub and blades. The blades are connected to the hub. The hub is connected to the main shaft of the nacelle. The blades can generate torque under the action of wind. The blades and the hub drive the main shaft of the nacelle to rotate, thereby converting wind energy into mechanical energy. The main shaft of the nacelle can be connected to the rotor of the generator, thereby converting mechanical energy into electrical energy.

[0062] Figure 2 Schematic showing the structure of a leaf. Figure 2 As shown, an embodiment of the present application provides a blade. The blade includes a main body and a pre-embedded bolt sleeve. The bolt sleeve of the blade can be connected to the hub by screws. The main body includes a blade tip and a blade root opposite to each other along the length direction. A mounting hole is provided at the blade root. The bolt sleeve can be embedded in the mounting hole. The bolt sleeve and the main body can be connected by bonding. In some embodiments, a resin adhesive can be used to bond the bolt sleeve and the main body. A vacuum infusion process can be used to infuse the adhesive between the bolt sleeve and the main body. The cured adhesive connects and fixes the bolt sleeve and the main body. In some embodiments, Figure 3 Schematic diagram showing the structure of the bolt sleeve. Figure 3 As shown, the outer surface of the bolt sleeve is arranged to be concave-convex, that is, the outer surface of the bolt sleeve has bosses and grooves arranged alternately, which is beneficial to increase the bonding area between the bolt sleeve and the adhesive and improve the connection force between the bolt sleeve and the main body.

[0063] An embodiment of the present application provides a pull-out force testing device for a pre-embedded bolt sleeve at the root of a wind turbine blade, which is used to perform a pull-out force test on the pre-embedded bolt sleeve, so as to facilitate judging whether the bolt sleeve can withstand a preset maximum pull-out force, thereby judging whether the bolt sleeve meets the use requirements.

[0064] Figure 4 The structure of the wind turbine blade root embedded bolt sleeve pull-out force testing device is schematically shown.

[0065] Figure 5 The structure of the wind turbine blade root embedded bolt sleeve pull-out force testing device is schematically shown. Figure 6 The partial cross-sectional structure of the wind turbine blade root embedded bolt sleeve pull-out force testing device is schematically shown. Figure 7 The structure of the first hinge is schematically shown. Figure 8 The structure of the second hinge is schematically shown.

[0066] See also Figures 4 to 8 As shown, the wind turbine blade root embedded bolt sleeve pull-out force testing device of the embodiment of the present application includes a first connecting assembly, a second connecting assembly and a pull rod.

[0067] The first connecting assembly includes a transfer seat and a first hinged member. The first hinged member includes a first component and a second component that are hinged to each other. The first component is connected to the transfer seat.

[0068] The second connecting assembly includes a bolt sleeve clamping member and a second hinged member. The second hinged member includes a third component and a fourth component hinged to each other. The third component of the second hinged member is connected to the bolt sleeve clamping member. The bolt sleeve clamping member is used to clamp the bolt sleeve to be tested.

[0069] The pull rod includes a first connection end and a second connection end which are arranged opposite to each other. Along the axial direction of the pull rod, the first hinge is arranged corresponding to the second hinge. The first connection end of the pull rod is connected to the second part of the first hinge. The second connection end of the pull rod is arranged facing the second hinge. The second connection end of the pull rod is used to connect the bolt sleeve to be tested.

[0070] The first connecting assembly and the second connecting assembly are independent of each other and do not interfere with each other. Along the axial direction of the pull rod, the first connecting assembly and the second connecting assembly can be arranged at intervals. The adapter is used to connect to an external structural member. For example, Fig. 9 The structure of the wind turbine blade root embedded bolt sleeve pull-out force test device is schematically shown. Fig. 9As shown, the wind turbine blade root embedded bolt sleeve pull-out force testing device also includes a load loader. The adapter can be connected to the load loader. For example, the adapter can be connected to the load loader through a connector such as a screw. In some embodiments, the axial direction of the pull rod is the same as the vertical direction. Along the vertical direction, the first connecting assembly and the second connecting assembly can be arranged at intervals.

[0071] The first component and the second component of the first hinged member are hinged to each other, so that the first component and the second component have rotational freedom. The first component is connected to the adapter. When the second component is subjected to external force, the second component can rotate relative to the first component.

[0072] When the wind turbine blade root embedded bolt sleeve pull-out force testing device of the embodiment of the present application is tested, the bolt sleeve clamping member clamps the bolt sleeve to fix the position of the bolt sleeve. The second connecting assembly and the pull rod are connected by the bolt sleeve, thereby realizing the force transmission between the second connecting assembly, the pull rod and the bolt sleeve. The fourth component of the second hinge is used to connect to an external structural member. For example, the fourth component of the second hinge can be connected to a load loader. For example, the fourth component of the second hinge can be connected to the load loader by a connector such as a screw.

[0073] When the pull-out force test device for the pre-embedded bolt sleeve at the root of a wind turbine blade is tested, the bolt sleeve to be tested is clamped on the bolt sleeve clamping member, and the second connecting end of the pull rod is connected to the bolt sleeve. Then, the fourth component of the adapter and the second hinge is respectively connected to the load loading machine. The load loading machine applies tensile forces in opposite directions to the fourth component of the adapter and the second hinge respectively, so as to load the pull-out load to the bolt sleeve through the first connecting component, the second connecting component and the pull rod. Since the pull-out force test device for the pre-embedded bolt sleeve at the root of a wind turbine blade of the embodiment of the present application includes a first hinge and a second hinge, during the loading process, the relative positions of the first component and the second component can be automatically adjusted by relative rotation, and the relative positions of the third component and the fourth component can be automatically adjusted by relative rotation, so as to ensure that the loading process is a tensile load, and ensure that the pull rod and the bolt sleeve bear the axial load, so that the bending load borne on the pull rod and the bolt sleeve can be controlled within the range that meets the test requirements.

[0074] If a large component force perpendicular to the axial direction of the tie rod is generated on the tie rod and the bolt sleeve after the load is applied, the tie rod and the bolt sleeve will bear a large bending load, causing the tie rod and the bolt sleeve to bend due to the large bending load, thereby affecting the credibility and accuracy of the bolt sleeve pull-out force test results.

[0075] The pull-out force testing device for the embedded bolt sleeve at the root of a wind turbine blade of the embodiment of the present application can perform load testing on the embedded bolt sleeve. The first connecting assembly, the second connecting assembly and the pull rod form a tooling for testing the bolt sleeve. When using the pull-out force testing device for the embedded bolt sleeve at the root of a wind turbine blade for testing, the bolt sleeve to be tested can be connected to the second connecting assembly, and the bolt sleeve can be connected to the pull rod. After completing the connection of the first connecting assembly, the second connecting assembly, the pull rod and the bolt sleeve, tensile forces in opposite directions can be applied to the fourth component of the adapter and the second hinge respectively, so as to apply a pull-out force to the pull rod and the bolt sleeve through the first connecting assembly and the second connecting assembly, so as to facilitate the judgment of whether the bolt sleeve can withstand the maximum pull-out force that meets the requirements, thereby judging whether the bolt sleeve meets the use requirements. The first connecting assembly and the second connecting assembly respectively include a first hinge and a second hinge, so that during the load loading process, the first hinge and the second hinge can adjust the relative position between the first component and the second component and the relative position between the third component and the fourth component in real time under the action of an external force, so as to ensure that the loading process is a tensile load, and to ensure that the pull rod and the bolt sleeve bear an axial load, so that the bending load borne on the pull rod and the bolt sleeve can be controlled within the range that meets the test requirements, thereby facilitating the reliability and accuracy of the test results.

[0076] In some achievable ways, the first component and the second component in the first hinge are ball-jointed. The first component and the second component have more rotational freedom, which is beneficial for the second component to be more flexible in rotating relative to the first component when the pull rod applies a tensile force to the second component, so that the first component and the second component can be relatively easily moved, effectively ensuring that the pull rod bears the axial load during the loading process, thereby ensuring that the bolt sleeve bears the axial load.

[0077] In some achievable ways, Fig.10 The partial cross-sectional structure of the first hinge is schematically shown. Fig.10 As shown, one of the first component and the second component is provided with a spherical recess, and the other is provided with a first spherical portion hinged to the spherical recess. At least part of the first spherical portion is located in the spherical recess. The outer surface of the first spherical portion matches the inner wall of the spherical recess. In the case where the pull rod applies a tensile force to the second component, the first spherical portion and the spherical recess can slide relative to each other to adjust the relative positions of the first component and the second component to ensure that the pull rod bears the axial load during the loading process. In the case where the pull rod applies a tensile force to the second component, the first component and the second component maintain a tight fit, so that the first spherical portion and the spherical recess maintain contact, so that there is no need to set an additional connector between the first component and the second component, which is beneficial to reduce the number of parts used.

[0078] For some examples, see Fig.10As shown, the first component includes a spherical recess. Along the axial direction of the pull rod, the opening of the spherical recess is arranged away from the second hinge. The second component includes a first spherical portion. When the pull rod applies a tensile force to the second component, the first spherical portion can apply a force along the axial direction of the pull rod to the spherical recess. Exemplarily, the axis of the pull rod passes through the center of the first spherical portion.

[0079] In some achievable ways, Fig.11 The structure of the adapter is schematically shown. Fig.12 The partial cross-sectional structure of the wind turbine blade root embedded bolt sleeve pull-out force test device is schematically shown. Fig.11 and Fig.12 As shown, the adapter seat includes a receiving groove. Along the axial direction of the pull rod, the opening of the receiving groove faces away from the second hinged member, and at least part of the first component is arranged in the receiving groove.

[0080] When the first component is connected to the adapter, the first component is subject to a force acting in a first direction. The first direction is perpendicular to the depth direction of the accommodating groove. When the first component is subject to a force acting in the first direction, the first component can be constrained by the adapter so that the first component will not be displaced in the first direction relative to the adapter, effectively reducing the possibility of displacement of the second component and the first connecting end of the pull rod due to displacement of the first component, thereby helping to reduce the possibility of an increase in the bending moment on the pull rod due to displacement of the first connecting end of the pull rod.

[0081] In some examples, the portion of the first component located in the receiving groove can match the shape of the receiving groove, so that the receiving groove provides installation positioning for the first component and improves assembly efficiency. Exemplarily, there is a transition fit between the first component and the receiving groove, which is conducive to reducing the gap between the first component and the adapter, so that the first component is not easy to shake relative to the adapter. Exemplarily, the receiving groove is cylindrical. The portion of the first component located in the receiving groove is cylindrical, or the first component is cylindrical as a whole.

[0082] In some possible implementations, see Figures 10 to 12 As shown, the first component includes a spherical recess. The second component includes a first spherical portion. The adapter includes a first through hole connected to the accommodating groove. The first component includes a second through hole connected to the spherical recess. The second component includes a third through hole penetrating the first spherical portion. The pull rod is inserted through the first through hole, the second through hole and the third through hole, and the first connecting end of the pull rod passes through the third through hole and is connected to the second component.

[0083] When the pull rod applies tensile force to the second component, the overall force of the second component is balanced, reducing the possibility of local stress concentration in the second component causing the second component to break or crack. The second component can transmit the force to the first component. Since the overall force of the second component is balanced, when the first component bears the compressive stress of the second component, the overall force of the first component is balanced, which is beneficial to reducing the possibility of local stress concentration in the first component causing the first component to break or crack. The adapter can effectively disperse the compressive stress transmitted from the first component to the adapter, improving the reliability of the test process and the stability of the connection.

[0084] The pull rod passes through the adapter, the first component and the second component in sequence. When the pull rod applies a tensile force to the second component, the second component presses against the first component, and the first component presses against the adapter, so that a tight fit is achieved between the adapter, the first component and the second component, so that no additional connector is required between the first component and the second component and between the first component and the adapter, which is conducive to reducing the number of parts used.

[0085] In some examples, the assembly process of the adapter, the first hinge, and the pull rod may be as follows: the first component is placed in the receiving groove of the adapter, and the first through hole and the second through hole are connected. Then, the first spherical portion of the second component is placed in the spherical recess of the first component, and the third through hole and the second through hole are connected. The first connecting end of the pull rod is passed through the first through hole, the second through hole, and the third through hole in sequence. The first connecting end of the pull rod passes through the third through hole and is connected to the second component.

[0086] During the assembly process, the pull rod needs to pass through the adapter, the first component, and the second component in sequence, and then the first connection end of the pull rod is connected to the second component. The first through hole, the second through hole, and the third through hole of the adapter can provide positioning for the pull rod to guide the pull rod to be quickly and accurately assembled with the adapter and the first hinge. Before the pull rod is connected to the second component, the first component and the second component are limited by the pull rod, so that the first component and the second component are not easy to fall off during the assembly process, which effectively reduces the operational difficulty of the assembly process and improves the assembly work efficiency.

[0087] In some possible implementations, see Fig.11 and Fig.12 As shown, the adapter seat includes a chamber. In a first direction, the chamber of the adapter seat has two opposite openings. The first direction is perpendicular to the axial direction of the first through hole. The axial direction of the first through hole can be the same as the depth direction of the receiving groove. The receiving groove is arranged on the inner wall of the adapter seat facing the chamber. The first connecting end of the pull rod is located in the chamber of the adapter seat.

[0088] The first component can be inserted through the opening of the chamber and docked with the receiving groove. The second component can be inserted through the opening of the chamber and connected to the first component. A tool can be used to extend into the chamber through the opening of the chamber to connect the first connection end of the pull rod that passes through the second component to the second component.

[0089] The adapter can provide protection for the first component, the second component and the first connecting end of the pull rod, effectively reducing the possibility of structural damage or deformation of the first component, the second component and the first connecting end of the pull rod due to accidental impact, thereby reducing the possibility of large errors in the load borne by the first component, the second component or the pull rod due to structural damage or deformation of the first component, the second component or the pull rod, thereby ensuring the credibility and accuracy of the test results.

[0090] During the process of connecting the adapter seat with the load loader, the load loader does not need to avoid the first component, the second component and the first connecting end of the pull rod, which reduces the difficulty of the connection operation between the adapter seat and the load loader. At the same time, it is beneficial to reduce the possibility of the first component, the second component and the first connecting end of the pull rod being accidentally hit by the load loader during the process of connecting the adapter seat and the load loader, causing structural damage or deformation.

[0091] In some achievable embodiments, in the first direction, the cavity of the adapter may have an opening.

[0092] In some examples, the adapter may include a first cylindrical portion and a second cylindrical portion. The diameter of the first cylindrical portion is greater than the diameter of the second cylindrical portion. The first cylindrical portion and the second cylindrical portion are coaxially arranged. The first cylindrical portion is used to connect to the load loader. For example, the first cylindrical portion can be connected to the load loader by a connecting member such as a screw. The second cylindrical portion is provided with a chamber and a receiving groove. The outer peripheral surface of the second cylindrical portion is provided with an opening of the chamber. The second cylindrical portion is connected to the first hinge.

[0093] Exemplarily, the first through hole and the second cylindrical portion are coaxially arranged. The receiving groove is a cylindrical groove. The receiving groove and the second cylindrical portion are coaxially arranged.

[0094] In some possible implementations, see Fig.12 As shown, the wind turbine blade root embedded bolt sleeve pull-out force testing device also includes an abutment. The first connection end of the pull rod is connected to the abutment. The pull rod is connected to the second component through the abutment. Along the axial direction of the pull rod, the second component is located between the abutment and the first component. The second component abuts against the first component. The abutment abuts against the second component.

[0095] When the pull rod bears tensile force, the pull rod can transmit the force to the second component through the abutment. When the pull rod applies tensile force to the second component, the abutment presses the second component, the second component presses the first component, and the first component presses the adapter, so that the adapter, the first component, the second component and the abutment can be tightly matched, so that there is no need to set additional connectors between the abutment and the second component, between the first component and the second component, and between the first component and the adapter, which is conducive to reducing the number of parts used.

[0096] In some examples, the abutment is threadedly connected to the first connection end of the pull rod. A large load can be carried between the abutment and the pull rod. Exemplarily, along the axial direction of the pull rod, a portion of the first connection end exceeds the surface of the abutment facing away from the second component. The pitch of the external thread set at the first connection end is P. The minimum dimension of the first connection end exceeding the abutment is 2P.

[0097] In some examples, along the axial direction of the pull rod, the first component, the second component and the abutment are sequentially stacked. Along the axial direction of the pull rod, the abutment is arranged on a side of the second component facing away from the first component.

[0098] In some achievable ways, the third component and the fourth component of the second hinge are ball-jointed. The third component and the fourth component have more rotational freedom, which is beneficial for the third component to be more flexible to rotate relative to the third and fourth components when the pull rod applies a tensile force to the bolt sleeve clamp, so that the third component and the fourth component can be relatively easily moved, effectively ensuring that the pull rod and the bolt sleeve bear the axial load during the loading process, so that the bending load on the pull rod and the bolt sleeve can be controlled within the range that meets the test requirements, thereby facilitating the reliability and accuracy of the test results.

[0099] In some achievable ways, Fig.13 The partial cross-sectional structure of the second hinge is schematically shown. Fig.13 As shown, in the second hinge, one of the third component and the fourth component includes a second spherical portion, and the other includes a spherical cavity hinged to the second spherical portion.

[0100] The outer surface of the second spherical portion matches the inner wall of the spherical cavity. When the pull rod applies a tensile force to the bolt sleeve, the second spherical portion and the spherical cavity can slide relative to each other to adjust the relative positions of the third component and the fourth component, ensuring that the pull rod and the bolt sleeve bear the axial load during the loading process. When the pull rod applies a tensile force to the bolt sleeve, the third component and the fourth component maintain a tight fit, so that the second spherical portion and the spherical cavity maintain contact, so that there is no need to set an additional connector between the third component and the fourth component, which is conducive to reducing the number of parts used.

[0101] In some examples, a portion of the second spherical portion is located in the spherical cavity. Alternatively, the second spherical portion is entirely located in the spherical cavity. The second spherical portion is not easily dislodged from the spherical cavity, thereby ensuring that the third component and the fourth component are not easily separated, which is conducive to reducing the difficulty of assembling the second hinged member and the bolt sleeve clamp.

[0102] In some examples, the third component includes a second spherical portion. The fourth component includes a spherical cavity. Exemplarily, the axis of the pull rod passes through the center of the second spherical portion.

[0103] In some achievable ways, Fig.14 The partial cross-sectional structure schematically shows the connection state between the wind turbine blade root embedded bolt sleeve pull-out force test device and the bolt sleeve. Figure 6 and Fig.14 As shown, the bolt sleeve clamp has a receiving hole. The receiving hole of the bolt sleeve clamp is used to receive the bolt sleeve. The bolt sleeve clamp is used to clamp the bolt sleeve received in the receiving hole. Along the axial direction of the pull rod, the second connecting end of the pull rod is arranged corresponding to the receiving hole.

[0104] The bolt sleeve clamp can hold the bolt sleeve from the outside of the bolt sleeve. On the one hand, it is helpful to simulate the state of the bolt sleeve actually buried in the main body of the blade, thereby improving the credibility and accuracy of the test results. On the other hand, it is helpful to increase the contact area between the bolt sleeve clamp and the bolt sleeve, improve the stability of the connection state between the bolt sleeve clamp and the bolt sleeve, and effectively reduce the possibility of test failure caused by separation between the bolt sleeve clamp and the bolt sleeve due to the pull-out force borne by the bolt sleeve not reaching the maximum test value.

[0105] In some examples, when the bolt sleeve clamping member clamps the bolt sleeve, the second connection end of the pull rod can be threadedly connected to the internal threaded hole section of the bolt sleeve. Exemplarily, the nominal diameter of the rod section with the external thread set at the second connection end is D. Along the axial direction of the pull rod, the length of the external thread of the second connection end engaging with the internal thread of the bolt sleeve is L. Wherein, L is greater than or equal to 1.5D.

[0106] In some examples, Fig.15 The structure of the clamping plate is shown schematically. Fig.16 The partial cross-sectional structure of the second connecting component is schematically shown. Fig.15 and Fig.16 As shown, the bolt sleeve clamping member includes at least two clamping plates. Along the circumference of the pull rod, the clamping plates are sequentially connected to form a receiving hole.

[0107] In the process of clamping the bolt sleeve using the bolt sleeve clamp, each clamping plate is arranged around the bolt sleeve and connected in sequence, and finally each clamping plate fixes the bolt sleeve. Each clamping plate is detachably connected. After the test is completed, each clamping plate is separated and removed in sequence, and the bolt sleeve is taken away. The bolt sleeve clamp includes at least two clamping plates, which is conducive to improving the connection convenience between the bolt sleeve clamp and the bolt sleeve.

[0108] For some examples, see Fig.14 and Fig.15 As shown, the inner wall of the clamping plate is provided with a convex part and a concave part. The convex part and the concave part are alternately arranged along the axial direction of the pull rod. The outer surface of the bolt sleeve is uneven. The outer surface of the bolt sleeve has bosses and grooves arranged alternately. The convex part arranged on the inner wall of the clamping plate can match the groove of the bolt sleeve, and the concave part arranged on the inner wall of the clamping plate can match the boss of the bolt sleeve. The convex part and the concave part of the clamping plate are respectively engaged with the groove and the boss of the bolt sleeve, so that on the one hand, it is beneficial to further increase the contact area between the bolt sleeve clamping part and the bolt sleeve, and improve the connection state stability between the bolt sleeve clamping part and the bolt sleeve. On the other hand, it is beneficial to fit the inner wall of the clamping plate with the outer surface of the bolt sleeve, so that when the clamping plate clamps and holds the bolt sleeve tightly, there is no local stress concentration area between the bolt sleeve and the clamping plate, which reduces the possibility of structural damage and deformation of the bolt sleeve or the clamping plate due to the local stress concentration area between the bolt sleeve and the clamping plate.

[0109] In some examples, the boss and the recess on the outer surface of the bolt sleeve may both be annular structures. The bosses and recesses of each clamping plate are spliced ​​to form an annular structure.

[0110] For some examples, see Fig.15 As shown, the clamping plate includes an arc-shaped plate and a connecting plate. A connecting plate is respectively arranged on both sides of the arc-shaped plate. Two adjacent clamping plates are connected to each other through the connecting plate. Connectors such as screws can be used to connect two adjacent connecting plates.

[0111] For some examples, see Fig.16 As shown, the second hinged member also includes a support rod. Both ends of the support rod are connected to the clamping plate respectively. The support rod and the clamping plate are detachably connected. For example, the support rod and the clamping plate are threadedly connected. The second spherical portion is connected to the support rod. At least part of the second spherical portion is located in the receiving hole of the bolt sleeve clamping member. The second hinged member is connected to the bolt sleeve clamping member through the support rod.

[0112] The second hinge can relatively easily adjust its position relative to the support rod to ensure that the axis of the receiving hole passes through the center of the second spherical portion. The way in which the second hinge is connected to the bolt sleeve clamp via the support rod is conducive to reducing the difficulty of connecting the second hinge and the bolt sleeve clamp, and is conducive to reducing the difficulty of adjusting the position of the second hinge relative to the bolt sleeve clamp, thereby ensuring that the position accuracy of the second hinge meets the test requirements and improving the credibility and accuracy of the test results.

[0113] Exemplarily, there are two clamping plates. Both ends of the support rod are connected to the two clamping plates. The boss and the recess on the outer surface of the bolt sleeve can be annular structures. The convex part and the recess of each clamping plate are semi-annular structures. The convex parts and the recess of the two clamping plates are spliced ​​to form an annular structure.

[0114] Exemplarily, a support rod is provided at the end of the clamping plate away from the first hinge. Exemplarily, a threaded hole can be provided at the end of the clamping plate away from the first hinge. The support rod is a round rod. The support rod can be provided with an external thread. The external thread of the support rod is threadedly connected with the threaded hole of the clamping plate.

[0115] Exemplarily, the axial direction of the support rod is perpendicular to the axial direction of the receiving hole. The third component includes a second spherical portion. The second spherical portion has a fourth through hole (see Fig.13 As shown). Along the axial direction of the support rod, the fourth through hole penetrates the third component. The second spherical portion is sleeved on the support rod. The fourth component includes a spherical cavity. Along the axial direction of the support rod, the spherical cavity penetrates the fourth component.

[0116] In some achievable ways, Fig.17 The partial structure of the wind turbine blade root embedded bolt sleeve pull-out force test device is schematically shown. Fig.17 As shown, the wind turbine blade root embedded bolt sleeve pull-out force testing device also includes a strain sensor. The strain sensor is arranged on the pull rod. The strain sensor is used to detect the axial load and bending load carried by the pull rod.

[0117] The strain sensor can detect the deformation of the tie rod itself during loading and output the corresponding strain value. According to the strain value of the strain sensor, the axial load and bending load of the tie rod can be calculated, so as to accurately determine whether the bending load of the tie rod has been controlled within the test requirements, which is conducive to improving the credibility and accuracy of the test results.

[0118] In some examples, the strain sensor may be a strain gauge, which may be bonded to the outer surface of the pull rod, making the connection between the strain sensor and the pull rod simple and easy to operate, and no additional connection structure is required on the pull rod, thereby reducing the manufacturing difficulty of the pull rod.

[0119] For example, along the circumference of the tie rod, more than two strain sensors are evenly spaced on the tie rod. Each strain sensor can detect the values ​​of the axial load and bending load borne by the tie rod, so as to judge whether the bending load borne by the tie rod has been controlled within the range required by the test through the strain values ​​of each strain sensor, which is conducive to further improving the credibility and accuracy of the test results.

[0120] Exemplarily, along the circumference of the tie rod, four strain sensors are evenly spaced on the tie rod, and the interval between two adjacent strain sensors is 90°.

[0121] Exemplarily, the area of ​​the pull rod where the strain sensor is arranged is a flat surface and is not provided with threads, so that the strain sensor can be easily bonded to the pull rod.

[0122] The present application provides a method for testing the pull-out force of a pre-embedded bolt sleeve at the root of a wind turbine blade, which comprises:

[0123] Provide adapter;

[0124] Providing a first hinged member, the first hinged member comprising a first component and a second component hinged to each other, connecting the first component to the adapter;

[0125] Provide bolt sleeve clamps;

[0126] Providing a second hinged member, the second hinged member comprising a third component and a fourth component hinged to each other, connecting the third component to the bolt sleeve clamping member;

[0127] Provide a bolt sleeve to be tested, and clamp the bolt sleeve using a bolt sleeve clamp;

[0128] providing a tie rod, connecting one end of the tie rod to the second component, and connecting the other end of the tie rod to the bolt sleeve;

[0129] Pulling forces in opposite directions are applied to the adapter seat and the fourth component of the second hinged member respectively, so as to load the pull rod and the bolt sleeve with a pulling load.

[0130] The pull-out force testing method for the embedded bolt sleeve at the root of a wind turbine blade in the embodiment of the present application can perform a load test on the embedded bolt sleeve. After completing the connection of the adapter, the first hinge, the bolt sleeve clamp, the second hinge, the pull rod and the bolt sleeve, a pull-out load can be applied to the pull rod and the bolt sleeve through the fourth component of the adapter and the second hinge, so as to facilitate the judgment of whether the bolt sleeve can withstand the maximum pull-out force that meets the requirements, thereby judging whether the bolt sleeve meets the use requirements. During the load loading process, the first hinge and the second hinge can adjust the relative position between the first component and the second component and the relative position between the third component and the fourth component in real time under the action of an external force, so as to ensure that the loading process is a tensile load, ensure that the pull rod and the bolt sleeve bear an axial load, so that the bending load borne on the pull rod and the bolt sleeve can be controlled within the range that meets the test requirements, thereby facilitating the reliability and accuracy of the test results.

[0131] In some achievable embodiments, the method for testing the pull-out force of the embedded bolt sleeve at the root of a wind turbine blade further includes providing a strain sensor, wherein four strain sensors are evenly spaced on the pull rod along the circumference of the pull rod, and the strain sensor is used to detect the axial load and bending load borne by the pull rod.

[0132] Before testing the bolt sleeve loading, check the coaxiality of the tie rod:

[0133] Apply pull-out forces in opposite directions to the adapter and the fourth component, respectively, and obtain the strain values ​​of the four strain sensors, which are ε1, ε2, ε3, and ε4.

[0134] When (ε1-ε3) / (ε1+ε3)=a, (ε2-ε4) / (ε2+ε4)=b, and (a ∧ 2+b ∧ 2) ∧ When 0.5<0.05, the pull rod meets the coaxiality requirement.

[0135] When the tie rod meets the coaxiality requirements, the bolt sleeve loading is tested. When the tie rod meets the coaxiality requirements, it can help ensure that the tie rod bears the axial load, so that the bending load on the tie rod can be controlled within the range that meets the test requirements, thereby ensuring the credibility and accuracy of the test results.

[0136] In some examples, the strain sensor may be a strain gauge. The strain sensor may be bonded to the outer surface of the pull rod.

[0137] In some examples, the tie rod may be a cylindrical rod having a circular cross section.

[0138] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A wind turbine blade root embedded bolt sleeve pull-out force testing device, characterized in that: include: A first connecting assembly includes a transfer seat and a first hinged member, wherein the first hinged member includes a first component and a second component hinged to each other, and the first component is connected to the transfer seat; A second connecting assembly includes a bolt sleeve clamp and a second hinged member, wherein the second hinged member includes a third component and a fourth component hinged to each other, wherein the third component is connected to the bolt sleeve clamp, and the bolt sleeve clamp is used to clamp the bolt sleeve to be tested; The pull rod comprises a first connecting end and a second connecting end which are arranged opposite to each other. Along the axial direction of the pull rod, the first hinge is arranged corresponding to the second hinge, the first connecting end is connected to the second component, the second connecting end is arranged facing the second hinge, and the second connecting end is used to connect the bolt sleeve to be tested.

2. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 1 is characterized in that: The first component and the second component of the first hinge are spherically hinged.

3. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 2 is characterized in that: One of the first component and the second component is provided with a spherical recess, and the other component is provided with a first spherical portion hingedly connected to the spherical recess.

4. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 3 is characterized in that: The adapter seat comprises a receiving groove, and along the axial direction of the pull rod, the opening of the receiving groove faces away from the second hinged component, and at least a part of the first component is arranged in the receiving groove.

5. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 4 is characterized in that: The first component includes the spherical recess, the second component includes the first spherical portion, the adapter includes a first through hole connected to the accommodating groove, the first component includes a second through hole connected to the spherical recess, the second component includes a third through hole passing through the first spherical portion, the pull rod is penetrated through the first through hole, the second through hole and the third through hole, and the first connecting end of the pull rod passes through the third through hole and is connected to the second component.

6. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 5 is characterized in that: The adapter seat includes a chamber, and in a first direction, the chamber has an opening or two opposite openings, the first direction is perpendicular to the axial direction of the first through hole, the accommodating groove is arranged on the inner wall of the adapter seat facing the chamber, and the first connecting end of the pull rod is located in the chamber.

7. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 5, characterized in that: The wind turbine blade root embedded bolt sleeve pull-out force testing device also includes an abutment member, the first connecting end of the pull rod is connected to the abutment member, along the axial direction of the pull rod, the second component is located between the abutment member and the first component, the second component abuts against the first component, and the abutment member abuts against the second component.

8. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to any one of claims 1 to 7, characterized in that: The third component and the fourth component of the second hinge are spherically hinged.

9. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 8, characterized in that: One of the third component and the fourth component includes a second spherical portion, and the other includes a spherical cavity hingedly connected to the second spherical portion.

10. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 9, characterized in that: The bolt sleeve clamp has a receiving hole, which is used to receive the bolt sleeve to be tested. The bolt sleeve clamp is used to clamp the bolt sleeve received in the receiving hole. Along the axial direction of the pull rod, the second connecting end of the pull rod is arranged corresponding to the receiving hole.

11. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 10, characterized in that: The bolt sleeve clamping member comprises at least two clamping plates, and along the circumference of the pull rod, the clamping plates are sequentially connected to form the accommodating hole.

12. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 11, characterized in that: The inner wall of the clamping plate is provided with convex parts and concave parts, and the convex parts and the concave parts are alternately arranged along the axial direction of the pull rod.

13. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 11, characterized in that: The second hinged member further comprises a support rod, both ends of which are respectively connected to the clamping plate, the second spherical portion is connected to the support rod, and at least a portion of the second spherical portion is located in the accommodating hole.

14. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to any one of claims 1 to 7, characterized in that: The wind turbine blade root embedded bolt sleeve pull-out force testing device further comprises a strain sensor, which is arranged on the pull rod and is used to detect the axial load and bending load borne by the pull rod.

15. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to claim 14, characterized in that: The strain type sensor is a strain gauge. Along the circumference of the pull rod, more than two strain type sensors are evenly spaced and arranged on the pull rod.

16. The wind turbine blade root embedded bolt sleeve pull-out force testing device according to any one of claims 1 to 7, characterized in that: The wind turbine blade root embedded bolt sleeve pull-out force testing device further includes a load loader, the adapter is connected to the load loader, and the fourth component of the second hinge is connected to the load loader.

17. A method for testing the pull-out force of pre-embedded bolt sleeves at the root of a wind turbine blade, characterized in that: include: Provide adapter; Providing a first hinged member, the first hinged member comprising a first component and a second component hinged to each other, connecting the first component to the adapter; Provide bolt sleeve clamps; Providing a second hinged member, the second hinged member comprising a third component and a fourth component hinged to each other, connecting the third component to the bolt sleeve clamping member; Providing a bolt sleeve to be tested, and clamping the bolt sleeve using the bolt sleeve clamping member; Providing a pull rod, connecting one end of the pull rod to the second component, and connecting the other end of the pull rod to the bolt sleeve; Pulling forces in opposite directions are applied to the adapter and the fourth component respectively, so as to apply a pulling load to the pull rod and the bolt sleeve.

18. The method for testing the pull-out force of the pre-embedded bolt sleeve at the root of a wind turbine blade according to claim 17, characterized in that: The wind turbine blade root embedded bolt sleeve pull-out force testing method further includes: A strain sensor is provided. Four strain sensors are evenly spaced on the pull rod along the circumference of the pull rod. The strain sensor is used to detect the axial load and bending load borne by the pull rod. Before testing the bolt sleeve loading, the pull rod is tested for coaxiality: Applying pulling forces in opposite directions to the adapter and the fourth component, respectively, to obtain strain values ​​of the four strain sensors, which are ε1, ε2, ε3, and ε4, respectively. When (ε1-ε3) / (ε1+ε3)=a, (ε2-ε4) / (ε2+ε4)=b, and (a ∧ 2+b ∧ 2) ∧ When 0.5<0.05, the pull rod meets the coaxiality requirement.

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