A wind power blade bolt sleeve test tool and a test system thereof

Abstract

The utility model belongs to mechanical field especially relates to a kind of wind power blade bolt sleeve test tool and its testing system.A kind of wind power blade bolt sleeve test tool, including upper pull rod, lower pull rod and the base for fixing bolt sleeve sample, bolt sleeve sample and base are connected with testing machine respectively by upper pull rod and lower pull rod, the both ends of the base are T type recess area, the both ends of bolt sleeve sample are fixed in the T type recess area of base by compatible T type screw and nut;The middle of base is circular test area, the diameter of circular test area is greater than the outer diameter of bolt sleeve sample, bolt sleeve sample is fixed on upper pull rod by fixing nut, the outer diameter of fixing nut is between the inner diameter of bolt sleeve and bolt sleeve outer diameter, after fastening of fixing nut, bolt sleeve sample is simultaneously subjected to pulling and pressing test by pulling or pressing force provided by upper pull rod.The utility model bolt sleeve test tool can carry out pulling fatigue test and pressing fatigue test.

Description

Technical Field

[0001] This utility model belongs to the field of machinery, and in particular relates to a testing fixture and testing system for wind turbine blade bolt sleeves. Background Technology

[0002] As a renewable and clean energy source, wind energy is receiving increasing attention, and the wind power industry is gradually becoming a mainstream new energy industry. After decades of development, China's wind turbine blade industry has grown from nothing to a complete industrial chain. With the rapid development and technological progress of China's wind power, China's wind turbine blade industry has reached the international level, actively participates in international competition, and fully demonstrates its strong competitive advantages.

[0003] The blades are the most critical components of wind turbine generators. They are becoming longer and heavier. The blades are bolted to the hub. During operation, the blades are constantly subjected to alternating loads, and the blade root bolt connection is also subjected to complex tensile or compressive loads. The bonding force between the bolts and the bolt sleeves becomes particularly important. Pulling out the bolt sleeves or damaging the bolts can lead to the failure of the blade root bolt connection, resulting in a serious tower collapse accident.

[0004] Currently, the blade root bolt sleeve is tested using existing blade root sections. The samples are large and heavy, and have a wedge-shaped surface, resulting in asymmetry between the left and right sides of the test samples. The accuracy of the results needs to be verified. Moreover, the bolt sleeve can only be tested in the tensile direction, and cannot be tested in the compressive direction, which is more likely to cause hidden dangers. Different models of bolt sleeves can only be tested in the thickness direction, and there is only one size. Each type requires a large number of experiments, and it is impossible to simulate the results of the experiments on the bolt sleeve per unit length using a digital model. Furthermore, the bolt spacing of different models of hubs is different, and different tooling must be made for each type, resulting in great waste.

[0005] To date, there is no data that can simultaneously characterize the tensile and compressive properties of blade root bolt sleeves, which has caused difficulties for technicians in evaluating the connection of blade root bolt sleeves. In view of this, in order to address the above problems, a test method and tooling for bolt sleeve fatigue were designed in the laboratory to effectively judge the fatigue performance of blade root bolt sleeves. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a bolt sleeve testing fixture that can perform both tensile fatigue and compressive fatigue tests.

[0007] A testing fixture for wind turbine blade bolt sleeves includes an upper pull rod, a lower pull rod, and a base for fixing bolt sleeve samples. The bolt sleeve samples and the base are connected to a testing machine via the upper and lower pull rods, respectively. The base has T-shaped grooves at both ends, and the two ends of the bolt sleeve samples are fixed to the T-shaped grooves of the base by matching T-shaped screws and nuts. The middle of the base has a circular testing area with a diameter larger than the outer diameter of the bolt sleeve samples. The bolt sleeve samples are fixed to the upper pull rod by fixing nuts, the outer diameter of which is between the inner and outer diameters of the bolt sleeve. After the fixing nuts are tightened, the bolt sleeve samples can be tested simultaneously by tensile or compressive forces provided by the upper pull rod.

[0008] Furthermore, T-screws of different lengths are available to fix bolt sleeve samples of different thicknesses onto the base.

[0009] Furthermore, the T-shaped groove area has a certain length, which is suitable for fixing bolt sleeve samples with different thread pitches on the base.

[0010] Furthermore, the upper and lower pull rods are respectively connected to the testing machine via wedge blocks.

[0011] In addition, this utility model also provides a wind turbine blade bolt sleeve testing system.

[0012] A wind turbine blade bolt sleeve testing system includes a bolt sleeve sample and a wind turbine blade bolt sleeve testing fixture. The bolt sleeve sample is obtained by cutting a long strip-shaped bolt sleeve prefabricated part with screw holes. The wind turbine blade bolt sleeve testing fixture includes an upper pull rod, a lower pull rod, and a base for fixing the bolt sleeve sample. The bolt sleeve sample and the base are connected to the testing machine via the upper pull rod and the lower pull rod, respectively. The two ends of the base are T-shaped groove areas. The two ends of the bolt sleeve sample are fixed to the T-shaped groove areas of the base by matching T-shaped screws and nuts. The middle of the base is a circular testing area with a diameter larger than the outer diameter of the bolt sleeve sample. The bolt sleeve sample is fixed to the upper pull rod by a fixing nut. The outer diameter of the fixing nut is between the inner diameter and the outer diameter of the bolt sleeve. After the fixing nut is tightened, the bolt sleeve sample can be tested simultaneously by tensile or compressive force provided by the upper pull rod.

[0013] Furthermore, the bolt sleeve sample has at least three screw holes.

[0014] Furthermore, the bolt sleeve prefabricated component is symmetrical from left to right.

[0015] Furthermore, the pitch and number of bolt holes of the prefabricated bolt sleeve can be prefabricated according to the product to be tested.

[0016] Furthermore, the bolt sleeve sample is obtained by transversely cutting a bolt sleeve prefabricated part according to the thickness requirements of the product to be tested.

[0017] This utility model of bolt sleeve testing fixture can perform both tensile and compressive fatigue tests. It can test bolt sleeve specimens of different thicknesses, and based on the results, establish mathematical models and empirical formulas applicable to all bolt sleeves. It maintains better alignment of the bolt sleeve, resulting in more accurate data. The bolt sleeve pitch can be adjusted by adjusting the T-type fastening screws to meet the testing requirements of various bolt sleeve models. It can also transform bolt sleeves with wedge-shaped surfaces into symmetrical bolt sleeve testing solutions. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the assembled structure of this utility model.

[0019] Figure 2 This is a schematic diagram of the base structure of this utility model.

[0020] Figure 3 This utility model embodiment shows a schematic diagram of the cutting of the bolt sleeve prefabricated component.

[0021] Figure 4 This utility model presents a schematic diagram of the compressive and tensile fatigue test forces.

[0022] In the figure, 1. Base; 1-1. T-shaped groove area; 1-2. Circular test area; 2-1. Upper pull rod; 2-2. Lower pull rod; 3. Fixing nut; 4. T-shaped screw; 5. Wedge block; 6. Bolt sleeve prefabricated part; 6-1. Bolt sleeve sample; 6-2. Screw hole. Detailed Implementation

[0023] The embodiments of this utility model are described in detail below, with examples of the embodiments shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0024] As attached Figure 1 As shown, a test fixture for wind turbine blade bolt sleeves includes the following main parts: Wedge block 5: Connects the upper pull rod 2-1 and the lower pull rod 2-2 to the testing machine; Upper tie rod 2-1: connects wedge block 5 and bolt sleeve specimen 6-1, providing experimental load; Pull-down rod 2-1: connects wedge block 5 and base 1; Base 1: Bearing function, fixing bolt sleeve sample 6-1; T-screw 4: Used with nuts to fix bolt sleeve samples 6-1 of different thicknesses onto base 1; Fixing nut 3: Fix bolt sleeve sample 6-1 to upper pull rod 2-1. The outer diameter of fixing nut 3 is larger than the inner diameter of bolt sleeve sample 6-1 and smaller than the outer diameter of bolt sleeve sample 6-1. After tightening, tensile and compressive tests can be performed simultaneously.

[0025] Reference Appendix Figure 2 Schematic diagram of the base shown Circular test area 1-2: The diameter of this area is larger than the outer diameter of the bolt sleeve specimen 6-1, so that the bolt sleeve specimen 6-1 is subjected to tensile or compressive force provided by the upper pull rod 2-1. T-groove area 1-1: This area can be used to fix bolt sleeve samples 6-1 with different thread pitches using T-screws 4. T-screws 4 are used in conjunction with nuts to fix bolt sleeve samples 6-1 with different thicknesses.

[0026] The test method for wind turbine blade bolt sleeves is as follows: I. Making a sample bolt sleeve 1) According to Figure 3 The example shown is a prefabricated bolt sleeve component 6 containing 3 bolt sleeves. 2) After demolding, the bolt sleeve prefabricated part 6 is cut into bolt sleeve samples 6-1 of uniform thickness in the thickness direction according to the design dimensions; bolt sleeve samples 6-1 of different thicknesses can be cut according to design requirements for testing.

[0027] Among them, the bolt sleeve prefabricated component 6 can be made in the laboratory or cut from the wind turbine blade, and there are two modes: three bolts and one bolt.

[0028] II. Experimental Procedure 1) According to Figure 1 Install wedge block 5 into the upper and lower clamps of the testing machine; 2) Fix the base 1 to the wedge block 5 using the pull rod 2-2; 3) Fix the bolt sleeve sample 6-1 to the upper pull rod 2-1, and fix the upper pull rod 2-1 to the wedge block 5; 4) Adjust the position of the testing machine and fix the bolt sleeve specimen 6-1 to the base 1 using T-screws 4; 5) As attached Figure 4 As shown, tensile and compressive forces are applied as needed for the test.

[0029] The above description is only a specific embodiment of the present utility model, but the technical features of the present utility model are not limited thereto. Any changes or modifications made by those skilled in the art within the scope of the present utility model are covered by the patent scope of the present utility model.

Claims

1. A testing fixture for wind turbine blade bolt sleeves, characterized in that: The test equipment includes an upper pull rod, a lower pull rod, and a base for fixing the bolt sleeve specimen. The bolt sleeve specimen and the base are connected to the testing machine via the upper pull rod and the lower pull rod, respectively. The base has T-shaped grooves at both ends, and the two ends of the bolt sleeve specimen are fixed to the T-shaped grooves of the base by matching T-shaped screws and nuts. The middle of the base has a circular test area with a diameter larger than the outer diameter of the bolt sleeve specimen. The bolt sleeve specimen is fixed to the upper pull rod by a fixing nut, the outer diameter of which is between the inner diameter and the outer diameter of the bolt sleeve. After the fixing nut is tightened, the bolt sleeve specimen can be subjected to tensile or compressive forces provided by the upper pull rod, allowing for simultaneous tensile and compressive testing.

2. The wind turbine blade bolt sleeve testing fixture according to claim 1, characterized in that: T-screws of different lengths are available to fix bolt sleeve samples of different thicknesses onto the base.

3. The wind turbine blade bolt sleeve testing fixture according to claim 1, characterized in that: The T-shaped groove area has a certain length and is suitable for fixing bolt sleeve samples with different thread pitches on the base.

4. The wind turbine blade bolt sleeve testing fixture according to claim 1, characterized in that: The upper and lower pull rods are connected to the testing machine via wedge blocks.

5. A wind turbine blade bolt sleeve testing system, characterized in that: The invention includes a bolt sleeve sample and a wind turbine blade bolt sleeve testing fixture as described in any one of claims 1-4, wherein the bolt sleeve sample is obtained by cutting a long strip-shaped bolt sleeve prefabricated part with a screw hole.

6. The wind turbine blade bolt sleeve testing system according to claim 5, characterized in that: The bolt sleeve sample has at least 3 screw holes.

7. The wind turbine blade bolt sleeve testing system according to claim 5, characterized in that: The prefabricated bolt sleeve components are symmetrical.

8. The wind turbine blade bolt sleeve testing system according to claim 5, characterized in that: The pitch and number of bolt holes of the prefabricated bolt sleeve can be prefabricated according to the product to be tested.

9. The wind turbine blade bolt sleeve testing system according to claim 5, characterized in that: The bolt sleeve sample was obtained by transversely cutting a prefabricated bolt sleeve according to the thickness requirements of the product to be tested.

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