C-shaped beam structure composite material rotor blade positioning and assembling method

Abstract

The invention relates to the technical field of rotor blade assembly, and discloses a C-shaped beam structure composite material rotor blade positioning and assembling method which comprises the following steps: S1, designing and using a positioning and assembling platform, and arranging a laser scanner to monitor the butt joint precision of a blade and a rotating shaft in real time; s2, preliminarily fixing the paddle and the rotating shaft through an adjusting clamp, and checking the preliminary positioning by using a laser scanner; s3, carrying out a thermocuring fixing process, namely heating the paddle to a preset temperature, fixing the paddle and the rotating shaft by adopting an adhesive after curing, and locking by using a mechanical clamp; s4, detecting the contact surface of the paddle and the rotating shaft by using a laser scanner; and S5, the connecting part of the paddle and the rotating shaft is reinforced through a bolt. The connection strength of the paddle and the rotating shaft is greater than or equal to 50MPa by adopting a thermocuring process and combining epoxy resin or a polyurethane-based adhesive, and the strength of the connection part is further improved through bolt reinforcement and enhanced curing treatment.

Description

Technical Field

[0001] The invention relates to the technical field of rotor blade assembly, and in particular to a positioning and assembly method for a C-beam structure composite material rotor blade. Background Art

[0002] In modern aerospace and wind power generation, rotor blades are one of the key components, bearing huge workloads and complex environmental conditions. Especially under high loads, high-speed rotation and extreme environments, the connection quality between the blades and the shaft plays a vital role in the stability and safety of the rotor system. The assembly quality of the rotor blades directly affects the performance of the entire system, including the dynamic balance, fatigue resistance and long-term reliability of the rotor.

[0003] The traditional connection between the blade and the shaft mainly relies on mechanical locking and ordinary adhesive fixation, but due to the lack of effective strengthening means and control, the strength of the connection parts is often insufficient, especially under high load and high-speed operation, it is easy to loosen, fatigue or break. This connection method cannot meet the modern high-strength and long-term operation requirements and has great safety risks. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a method for positioning and assembling a composite rotor blade with a C-beam structure, which solves the problem that the traditional connection between the blade and the rotating shaft mainly relies on mechanical locking and ordinary adhesive fixation, but due to the lack of effective strengthening means and control, it often leads to insufficient strength of the connection part.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: A positioning and assembly method for a C-beam structure composite rotor blade comprises the following steps: S1. Design and use a positioning assembly platform, which consists of an adjustment bracket and a positioning mold, and is equipped with a laser scanner to monitor the docking accuracy between the blade and the shaft in real time; S2. Preliminarily fix the propeller blade to the rotating shaft through the adjustment fixture, and use the laser scanner to check the preliminary positioning. If it exceeds the error range, make fine adjustments; S3, performing a heat curing fixing process, including heating the blade to a predetermined temperature, fixing the blade to the rotating shaft with an adhesive after curing, and locking the blade with a mechanical clamp; S4. Use a laser scanner to detect the contact surface between the blade and the shaft, and make fine adjustments if it exceeds the error range; S5. Reinforce the connection between the blade and the shaft with bolts, and perform enhanced curing treatment to improve the connection strength.

[0006] Preferably, the positioning accuracy of the positioning assembly platform is ±0.05 mm, and the accuracy of the laser scanner is ±0.01 mm.

[0007] Preferably, the adjustment fixture provides at least 4-point positioning, and the positioning error is controlled within ±0.05 mm.

[0008] Preferably, the adhesive used in the thermal curing process is an epoxy resin or polyurethane-based adhesive, and the bonding strength after curing reaches ≥50 MPa.

[0009] Preferably, the specification of the bolt is M6-M10 level, the tensile strength of the bolt is ≥900MPa, and the fixing torque is 5-10Nm.

[0010] Preferably, the heating temperature in the thermal curing process is 70-120°C, the curing time is 1-3 hours, and the temperature control accuracy is controlled within ±2°C.

[0011] Preferably, the connection part is treated with epoxy resin reinforcement and curing to increase the connection strength to more than 120% of the original connection strength.

[0012] Preferably, the heat curing process in step S3 further comprises pre-treating the adhesive, wherein the pre-treating comprises heating the adhesive to 60-80° C. for pre-curing.

[0013] Preferably, when the laser scanner detects the contact surface between the blade and the rotating shaft in step S4, it further includes using a high-frequency ultrasonic scanner to perform non-destructive testing on the contact surface.

[0014] The present invention provides a positioning and assembly method for a C-beam structure composite material rotor blade. It has the following beneficial effects: 1. The present invention uses a thermal curing process combined with epoxy resin or polyurethane-based adhesive to achieve a connection strength of ≥50MPa between the blade and the shaft, and further improves the strength of the connection through bolt reinforcement and enhanced curing treatment. This allows the rotor to operate reliably in extreme working environments such as high speed, high load, and high vibration, and improves the safety and durability of the connection.

[0015] 2. The present invention adopts efficient adjustment fixtures and automatic detection systems (laser scanners, ultrasonic detection, etc.), which reduces the cumbersome steps in traditional assembly methods. It simplifies the assembly process, improves production efficiency, reduces manual intervention, reduces error rates, improves assembly consistency and repeatability, and meets the needs of mass production.

[0016] 3. The present invention uses a high-precision positioning assembly platform and a laser scanner (with an accuracy of ±0.01mm) to achieve high-precision docking between the blade and the shaft, and the positioning error is controlled within ±0.05mm. This effectively reduces the error in the assembly process, ensures the balance of the rotor at high-speed rotation, thereby improving the stability and performance of the rotor, and meeting the application requirements of aerospace and other fields with high-precision requirements.

[0017] 4. The present invention realizes high-precision, all-round non-destructive testing by combining the laser scanner with the ultrasonic scanner. The quality of the contact surface between the blade and the shaft can be monitored in real time during the assembly process, and minor defects can be discovered and corrected in time, avoiding failures caused by potential defects, thereby significantly improving the long-term reliability and safety of the rotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The present invention is a flow chart of a method for positioning and assembling a composite material rotor blade having a C-beam structure. DETAILED DESCRIPTION

[0019] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Please see attached Figure 1 The embodiment of the present invention provides a method for positioning and assembling a composite rotor blade having a C-beam structure, comprising the following steps: S1. Design and use a positioning assembly platform, which consists of an adjustment bracket and a positioning mold, and is equipped with a laser scanner to monitor the docking accuracy between the blade and the shaft in real time; S2. Preliminarily fix the propeller blade to the rotating shaft through the adjustment fixture, and use the laser scanner to check the preliminary positioning. If it exceeds the error range, make fine adjustments; S3, performing a heat curing fixing process, including heating the blade to a predetermined temperature, fixing the blade to the rotating shaft with an adhesive after curing, and locking the blade with a mechanical clamp; S4. Use a laser scanner to detect the contact surface between the blade and the shaft, and make fine adjustments if it exceeds the error range; S5. Reinforce the connection between the blade and the shaft with bolts, and perform enhanced curing treatment to improve the connection strength.

[0021] Specifically, this method ensures the precise docking of the blades and the shaft through multi-point precise positioning and high-precision detection. The positioning and detection of each step rely on high-precision mechanical platforms and advanced technologies such as lasers and ultrasound to ensure that the relative position error between the blades and the shaft is controlled at the micron level. This assembly method is not only suitable for the rotor blades of small drones, but also for the rotor assembly of large aerospace vehicles, and has wide applicability.

[0022] This method significantly improves the accuracy and stability of the connection between the blade and the shaft through the comprehensive application of multiple high-precision technologies, reduces assembly errors, and improves the mechanical properties and reliability of the final product. Through laser scanning and ultrasonic testing, assembly errors and potential defects can be discovered at an early stage, avoiding possible failures during later use and ensuring the safety and service life of the rotor system.

[0023] The positioning accuracy of the positioning assembly platform is ±0.05mm, and the accuracy of the laser scanner is ±0.01mm.

[0024] Specifically, the positioning platform is made of high-rigidity materials, and the design takes into account shock absorption and temperature control performance. The laser scanner is equipped with a high-precision optical sensor, which ensures that the position error is controlled within ±0.05mm by providing real-time feedback on the relative position between the blade and the shaft. The accuracy of the laser scanner is ±0.01mm, which can efficiently and accurately detect position deviations in each assembly step.

[0025] Precise positioning accuracy can ensure the matching accuracy between the blades and the shaft, improve the dynamic stability of the rotor, reduce vibration during operation, and extend the service life of the blades and shaft. The high-precision measurement of the laser scanner ensures that there are no large errors during the assembly process, reduces the subsequent adjustment and correction work, and improves production efficiency.

[0026] The adjustment fixture provides at least 4-point positioning, and the positioning error is controlled within ±0.05mm.

[0027] Specifically, the adjustment fixture uses a mechanical precision adjustment device that can automatically adjust according to the different sizes of the blades and the shaft, providing at least four precise positioning points. Each positioning point is controlled by a precision screw adjustment mechanism to ensure that the fixture can provide good fixation at the connection between the blade and the shaft, and control the error within ±0.05mm.

[0028] Through multi-point precise positioning, the error accumulation caused by single-point positioning can be effectively avoided, ensuring the matching accuracy between the blade and the shaft. In addition, the design of the adjustment fixture can adapt to different types of blades, with high versatility and flexibility. High-precision positioning can further reduce the subsequent correction process and improve assembly efficiency.

[0029] The adhesive used in the thermal curing process is an epoxy resin or polyurethane-based adhesive, and the bonding strength after curing reaches ≥50MPa.

[0030] Specifically, in the thermal curing process, the adhesive used is a high-performance epoxy resin or polyurethane-based adhesive, which has excellent tensile strength and temperature resistance and can provide a bonding strength of at least 50MPa after curing. By controlling the curing temperature and time, the best effect of bonding the adhesive to the composite material is ensured.

[0031] Choosing epoxy or polyurethane-based adhesives can improve the tensile strength and durability of the connection, thereby improving the stability and safety of the connection between the blade and the shaft. Adhesives with a strength of ≥50MPa can withstand high-speed rotation and high-frequency vibration working environments, extending the service life of the rotor.

[0032] Epoxy resin is a type of polymer material with excellent bonding properties, usually formed by cross-linking of epoxy groups with hardeners (such as amines or anhydrides). When epoxy resin is used as an adhesive, it is usually used in environments that require high-strength bonding.

[0033] Key Features: High Bond Strength: Epoxy resins can form strong bonds between a variety of materials (such as metals, ceramics, plastics and composites), and the bond strength is generally very high.

[0034] Excellent heat resistance and chemical resistance: After curing, epoxy resin has excellent resistance to high temperature, solvents and corrosion, and is suitable for use in harsh environments.

[0035] Excellent structural properties: After curing, epoxy resin forms a hard and strong structure that can withstand greater mechanical stress.

[0036] Low shrinkage: During the curing process, the volume shrinkage of epoxy resin is small, which is conducive to maintaining the accuracy of the connection part.

[0037] Polyurethane-based adhesives are formed by the reaction of polyurethane resins and curing agents (such as isocyanates). Polyurethane adhesives have strong elasticity and flexibility, and show excellent performance in many applications that need to withstand impact and deformation.

[0038] Key Features: Elasticity and flexibility: Polyurethane adhesives have good elasticity and can absorb certain shocks and vibrations, so they are suitable for structures that need to withstand greater stress and deformation.

[0039] Good durability and chemical resistance: Polyurethane adhesives can maintain high bonding strength in various environments and are resistant to oil, solvents, UV rays, etc.

[0040] Strong adaptability: Polyurethane adhesives can be used in humid environments and are not affected by some harsh climatic conditions.

[0041] Good Adhesion: Polyurethane-based adhesives bond well to a variety of materials, including metal, plastic, glass, wood, composites, etc.

[0042] The specifications of the bolts are M6-M10 level, the tensile strength of the bolts is ≥900MPa, and the fixing torque is 5-10Nm.

[0043] Specifically, high-strength titanium alloy bolts of M6 to M10 grade are used at the connection between the blade and the shaft, and each bolt is tightened to a set torque of 5-10Nm using an electronic torque tool. High-strength bolts can effectively resist the stress caused by the high-speed rotation of the rotor, ensuring a stable and reliable connection.

[0044] High tensile strength titanium alloy bolts not only provide sufficient strength, but also effectively resist corrosion, and are particularly suitable for high-end applications such as aerospace and drones. Precise torque control avoids over-tightening or over-loosening of the bolts, further improving the strength and reliability of the connection.

[0045] The heating temperature in the thermal curing process is 70-120°C, the curing time is 1-3 hours, and the temperature control accuracy is controlled within ±2°C.

[0046] Specifically, an advanced temperature control system is used to strictly control the heating temperature within the range of 70-120°C, and the temperature control system is used for real-time monitoring to ensure that the temperature fluctuation does not exceed ±2°C. The curing time is adjusted to 1-3 hours according to the characteristics of the material to ensure that the material is fully cured.

[0047] Precise temperature control can avoid unstable adhesive performance caused by temperature fluctuations, thereby ensuring the best bonding effect and improving the overall mechanical properties of the composite material. The stable curing process ensures the long-term reliability of the connection between the blade and the shaft.

[0048] The connection part is treated with epoxy resin reinforcement and curing to increase the connection strength to more than 120% of the original connection strength.

[0049] Specifically, epoxy resin is applied to the connection between the blade and the shaft to enhance the curing process. The enhanced curing material can effectively improve the connection strength, increasing the tensile strength of the connection to more than 120% of the original. Through the curing effect of epoxy resin, tiny gaps and irregular surfaces can be better filled to ensure the tightness of the connection.

[0050] By enhancing the curing treatment, the strength and durability of the connection part can be significantly improved, especially in an environment with frequent vibration and high-intensity loads, which can effectively extend the service life of the product and reduce the possibility of failure.

[0051] The heat curing process in step S3 further includes pre-treating the adhesive, and the pre-treating includes heating the adhesive to 60-80° C. for pre-curing.

[0052] Specifically, before the formal heat curing, the adhesive is pre-treated by heating the adhesive to 60-80°C and maintaining it for a certain period of time for pre-curing to improve the initial adhesion strength between the adhesive and the composite material. During the heating process, the chemical structure of the adhesive is partially cross-linked, thereby enhancing its subsequent bonding effect.

[0053] Through pre-curing treatment, the fluidity of the adhesive is reduced, and a cross-linked structure is initially formed, which significantly improves its adhesion to the surface of the blade and the shaft. This can reduce the fluidity of the adhesive during the formal curing process, improve positioning stability, and further enhance the bonding strength and durability of the connection parts, ensuring stability in high-stress environments.

[0054] When the laser scanner detects the contact surface between the blade and the rotating shaft in step S4, it further includes using a high-frequency ultrasonic scanner to perform non-destructive testing on the contact surface.

[0055] Specifically, after the laser scanner completes the initial inspection, a high-frequency ultrasonic scanner is used to perform non-destructive inspection on the contact surface between the blade and the shaft. The high-frequency ultrasonic scanner can detect possible tiny defects (such as pores, microcracks, etc.) inside the bonding surface and provide more in-depth structural information than laser scanning. The frequency of the ultrasonic wave is in the range of 2-10MHz to ensure the penetration depth and defect detection capability of the composite material.

[0056] Laser scanners can only detect surface or near-surface accuracy issues, while ultrasonic scanners can non-destructively detect possible tiny defects in the contact surface between the blade and the shaft, thereby ensuring the structural integrity of the bonding surface and the firmness of the connection. The combination of the two detection methods can eliminate potential problems to the greatest extent possible, ensure assembly quality, and thus improve the overall safety and durability of the rotor blades. This is particularly critical for applications in aerospace and drones, and helps reduce the risk of accidents caused by assembly defects.

[0057] The following is an introduction in conjunction with specific embodiments: Example 1: High-precision structural positioning and assembly 1. Background conditions This embodiment is suitable for the assembly of rotor blades of large aircraft, which requires extremely high precision and durability, and the rotor needs to withstand high-speed rotation and complex aerodynamic loads.

[0058] 2. Assembly process S1. Positioning assembly platform design: Use high-rigidity steel positioning assembly platform, the bracket and mold are made of steel alloy, the positioning accuracy reaches ±0.05mm. Equipped with precision laser scanner, the accuracy reaches ±0.01mm.

[0059] S2. Initial fixation of the blades: Initial positioning is performed using a four-point adjustable clamp, which is made of high-strength alloy to provide sufficient rigidity and precision.

[0060] S3, thermal curing fixing process: heating temperature is 100°C, curing time is 3 hours, using pretreated epoxy resin adhesive, first preheat the adhesive to 70°C for pre-curing.

[0061] S4. Laser and ultrasonic testing: After the laser scanning is completed, the bonding surface is further non-destructively tested using an ultrasonic scanner to ensure that there are no inherent defects.

[0062] S5, reinforcement and enhanced curing: Use M8 titanium alloy bolts with a fixing torque of 8Nm. Epoxy resin is used for enhanced curing, and the strength after curing is increased to 150% of the original strength.

[0063] 3. Beneficial effects The high-precision positioning and detection process ensures the dynamic balance of the rotor under high-speed working conditions, greatly improving the safety and durability of the rotor and being able to cope with extreme operating conditions.

[0064] Example 2: Assembly of high-speed rotor in low temperature environment 1. Background conditions This embodiment is suitable for the assembly of rotor blades working in a low temperature environment (such as a polar environment), and requires the adhesive to maintain good strength and stability even at low temperatures.

[0065] 2. Assembly process S1. Positioning assembly platform design: The assembly platform is made of a combination of composite materials and metal. The platform has good thermal isolation performance to ensure that the temperature during the assembly process is not affected by the environment.

[0066] S2. Preliminary fixation of the propeller blades: Use a fixture suitable for low-temperature environments to position them, and maintain the positioning temperature through a built-in heating element.

[0067] S3, thermal curing fixing process: heating temperature is 70 ℃, curing time is 3 hours, using epoxy resin adhesive designed for low temperature environment, pretreatment temperature is 60 ℃.

[0068] S4. Laser and ultrasonic detection: Laser scanners are used in combination with ultrasonic scanners, and special antifreeze protection devices are used in low temperature environments to ensure the normal operation of the equipment.

[0069] S5. Reinforcement and enhanced curing: Use M8 low-temperature resistant titanium alloy bolts with a fixing torque of 8Nm and epoxy resin enhanced curing to increase the curing strength to more than 150%.

[0070] 3. Beneficial effects By applying cryogenic protection technology to assembly platforms, fixtures and testing equipment, the assembly process in low-temperature environments can proceed smoothly. Low-temperature-specific epoxy resin adhesives can also maintain high strength and adhesion in extreme environments, ensuring that the rotor has good working performance and reliability in extremely cold conditions.

[0071] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for positioning and assembling a C-beam structure composite rotor blade, characterized in that: The following steps are involved: S1. Design and use a positioning assembly platform, which consists of an adjustment bracket and a positioning mold, and is equipped with a laser scanner to monitor the docking accuracy between the blade and the shaft in real time; S2. Preliminarily fix the propeller blade to the rotating shaft through the adjustment fixture, and use the laser scanner to check the preliminary positioning. If it exceeds the error range, make fine adjustments; S3, performing a heat curing fixing process, including heating the blade to a predetermined temperature, fixing the blade to the rotating shaft with an adhesive after curing, and locking the blade with a mechanical clamp; S4. Use a laser scanner to detect the contact surface between the blade and the shaft, and make fine adjustments if it exceeds the error range; S5. Reinforce the connection between the blade and the shaft with bolts, and perform enhanced curing treatment to improve the connection strength.

2. The positioning and assembly method of a C-beam structure composite rotor blade according to claim 1, characterized in that: The positioning accuracy of the positioning assembly platform is ±0.05 mm, and the accuracy of the laser scanner is ±0.01 mm.

3. The positioning and assembly method of a C-beam structure composite rotor blade according to claim 1, characterized in that: The adjustment fixture provides at least 4-point positioning, and the positioning error is controlled within ±0.05mm.

4. The positioning and assembly method of a C-beam structure composite material rotor blade according to claim 1, characterized in that: The adhesive used in the thermal curing process is an epoxy resin or polyurethane-based adhesive, and the bonding strength after curing reaches ≥50MPa.

5. The positioning and assembly method of a C-beam structure composite rotor blade according to claim 1, characterized in that: The specification of the bolt is M6-M10 level, the tensile strength of the bolt is ≥900MPa, and the fixing torque is 5-10Nm.

6. The positioning and assembly method of a C-beam structure composite material rotor blade according to claim 1, characterized in that: The heating temperature in the thermal curing process is 70-120° C., the curing time is 1-3 hours, and the temperature control accuracy is controlled within ±2° C.

7. The positioning and assembly method of a C-beam structure composite material rotor blade according to claim 1, characterized in that: The connection part is treated with epoxy resin reinforcement and curing to increase the connection strength to more than 120% of the original connection strength.

8. The positioning and assembly method of a C-beam structure composite material rotor blade according to claim 1, characterized in that: The heat curing process in step S3 further includes pre-treating the adhesive, wherein the pre-treating includes heating the adhesive to 60-80° C. for pre-curing.

9. The positioning and assembly method of a C-beam structure composite material rotor blade according to claim 1, characterized in that: When the laser scanner detects the contact surface between the blade and the rotating shaft in step S4, it further includes using a high-frequency ultrasonic scanner to perform non-destructive testing on the contact surface.

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