Rapid in-situ detection method for aero-engine wheel disc and blade tenon

Abstract

The invention relates to the technical field of electromagnetic eddy current nondestructive testing, and discloses a rapid in-situ detection method for an aero-engine wheel disc and a blade tenon, which comprises the following steps of: covering a high-precision array eddy current detection sensor on the side surface of the blade tenon and the wheel disc; therefore, a high-definition array eddy current imaging graph of the whole wheel disc and the blade tenon can be obtained, further, in-service in-situ detection of the whole wheel disc and the blade tenon can be rapidly completed in combination with a video image, and the integrity of the whole wheel disc and the blade tenon can be evaluated. According to the detection method, the in-situ detection efficiency of the in-service aviation aircraft engine is greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of electromagnetic eddy current nondestructive testing, and in particular to a rapid in-situ testing method for a wheel disc and a blade tenon of an aero-engine. Background Art

[0002] Aircraft engine blades and wheels are key components to ensure flight safety. In view of their importance, countries around the world, whether civil or military aircraft, must conduct regular or situation-based inspection and maintenance on them. Most of the current inspections are carried out by disassembling the blades or performing visual inspections or eddy current flaw detection one by one in situ with an endoscope or eddy current sensor. Among them, the existing in-situ eddy current detection method is to use an eddy current detection sensor to detect the entire wheel and its blade tenons (usually there are dozens or even hundreds of blades) one by one. This method has extremely low detection efficiency. If an emergency occurs, this inefficient working method will seriously affect the performance of the aircraft. The present invention is developed and improved on the basis of the existing technology, and strives to solve the above problems. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a method for rapid in-situ detection of an aircraft engine wheel disc and a blade tenon, which is implemented as follows:

[0004] A rapid in-situ detection method for an aircraft engine wheel disc and a blade tenon comprises the following steps:

[0005] 1) Design of detection sensor:

[0006] The detection sensor is an array eddy current detection sensor, which includes a supporting spring, a plurality of small-diameter cylindrical coils, and a micro-planar encoding disk.

[0007] The plurality of small-diameter cylindrical coils are arranged in an array and embedded on the surface of the supporting spring sheet, and the side surfaces of the small-diameter cylindrical coils face the surface of the supporting spring sheet;

[0008] The micro-plane encoding disk is embedded on the front end surface of the supporting spring sheet;

[0009] Arc-shaped bending edges are arranged on both sides of the supporting spring sheet;

[0010] 2) Installation of the detection sensor: The detection sensor described in step 1) is fixedly mounted on the side of the tenon of the engine blade to be tested and on the wheel disc;

[0011] 3) Implementation of detection: The engine turbine disc is slowly rotated by external force, so that the engine turbine disc and blades rotate one circle relative to the detection sensor. During this process, the detection sensor scans and obtains a high-definition array eddy current imaging image of the entire wheel disc and blade tenon.

[0012] Furthermore, in step 3), the working mode of the detection sensor is a high-frequency multi-frequency variable array excitation mode, and the high-frequency multi-frequency variable array excitation mode uses an excitation frequency range of 10kHz to 1MHz to excite the detection sensor, and is also multi-frequency excitation and variable array detection.

[0013] Furthermore, combined with a video probe, video image information of the complex and narrow space of the engine can be obtained, so as to quickly complete the surface defect detection of the entire wheel and blade tenon.

[0014] Compared with the existing ones, this application can obtain the following technical effects:

[0015] The present invention adopts an array eddy current detection sensor, which is covered on the side of the engine blade tenon to be detected and the wheel disc. By designing supporting spring pieces with arc-shaped bent edges on both sides and a number of small-diameter cylindrical coils arranged in a special arrangement on the supporting spring pieces, it is realized that in the process of rotating the engine eddy current disk for whole-disk detection, the relative jump caused by the assembly and processing errors of the blades and the wheel disc can be overcome, and the resistance to the rotation of the eddy current disk can be reduced. On the one hand, the detection sensitivity of the array eddy current detection sensor can be improved to obtain a stable and reliable eddy current detection signal, and on the other hand, the damage rate of the eddy current detection sensor can be reduced to save the detection cost. At the same time, by setting a synchronous positioning micro-plane encoding disk on the eddy current detection sensor to synchronously obtain the positioning signal and perform data fusion processing with the array eddy current detection signal, and then combining the video image information, it is realized to quickly obtain a high-definition array eddy current imaging image of the entire wheel disc and the blade tenon, thereby efficiently completing the surface defect detection of the entire wheel disc and the blade tenon, and the detection accuracy is high and the detection result is reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the examples of the present invention or the technical solutions in the prior art or the drawings required for use in the description of the prior art, a brief introduction is given. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 This is a schematic diagram of the aircraft engine blades and disc.

[0018] Figure 2 The figure is a schematic diagram of the structure of an array eddy current detection sensor under an embodiment.

[0019] Figure 3 The figure is a schematic diagram of the structure of an array eddy current detection sensor under another embodiment.

[0020] Figure 4 The figure is a schematic diagram of the structure of an array eddy current detection sensor under another embodiment.

[0021] Figure 5 This is a schematic diagram of the oblique cylindrical coil structure.

[0022] Figure 6 It is a schematic diagram of the overall structure of the detection probe of the present invention.

[0023] In the figure,

[0024] 10-blade; 20-tenon; 30-wheel disc; 40-crack;

[0025] 50 - detection sensor, 51 - supporting spring, 52 - cylindrical coil, 53 - micro flat encoding disk, 54 - arc-shaped bending edge.

[0026] 60-handle;

[0027] 70-Bend the probe rod. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but only represents selected embodiments of the present invention.

[0029] The detection of the engine turbine disk is an important part to ensure the safety and performance of the aircraft engine. As a key component of the engine, the turbine disk is subjected to a high temperature, high pressure and high speed working environment, so its detection process needs to strictly follow the standards and procedures. Due to the complexity of the detection environment, it is difficult for conventional detection sensors to achieve effective in-situ detection or the detection efficiency is low, and it is difficult to meet the use requirements. Therefore, the present invention studies a high-precision variable array eddy current sensor, covers the array eddy current sensor on the blade tenon and the wheel disc, and rotates the wheel disc to perform a rapid detection of the entire wheel disc and the blade tenon 20. On this basis, since there may be assembly and processing errors when the tenon 20 of the blade 10 and the tenon of the wheel disc 30 are organized and matched, when the rotating wheel disc 30 is performed for rapid imaging scanning, it is inevitable that there is a relative jump between the blade 10 and the wheel disc 30. Although the amplitude of the jump is not large, it will still affect the sensitivity of the high-frequency eddy current detection method, and the sensor may also be stuck and damaged. In order to overcome this problem, the present invention discloses a rapid in-situ detection method, and the specific method is as follows:

[0030] A rapid in-situ detection method for an aircraft engine wheel disc and a blade tenon comprises the following steps:

[0031] 1) Design of detection sensor:

[0032] The detection sensor 50 is an array eddy current detection sensor, which includes a supporting spring 51 , a plurality of small-diameter cylindrical coils 52 , and a miniature planar encoding disk 53 .

[0033] The plurality of small diameter cylindrical coils 52 are arranged in an array and embedded on the surface of the supporting spring sheet 51, and the side of the small diameter cylindrical coil 52 faces the surface of the supporting spring sheet 51; the small diameter cylindrical coils 52 are arranged in an array, which can effectively avoid missed detection. In this embodiment, the cross section of the small diameter cylindrical coils 52 is rectangular and is arranged in double rows in an interlaced manner. Figure 5 In other embodiments, it can also be set as a special-shaped coil with an oblique columnar shape and a diamond-shaped cross section, and arranged in a straight line. The side of the cylindrical coil 52 faces the surface of the supporting spring 51, that is, it uses the side of the cylindrical coil 52 as the detection surface, which can not only better adapt to the tiny jump caused by the assembly and processing errors between the blades and the wheel disc, but also make the detection sensor have consistent circumferential detection sensitivity.

[0034] The micro-plane encoding disk 53 is embedded on the front end surface of the supporting spring sheet 51; in other embodiments, the encoding disk can also be set on the external hand-cranked transmission mechanism of the wheel, and then data fusion processing is performed with the eddy current detection structure. In this embodiment, the micro-plane encoding disk 53 is directly embedded in the detection sensor and integrated with the detection sensor to improve the resolution and improve the detection effect of array eddy current scanning imaging.

[0035] The two sides of the supporting spring sheet 51 are provided with arc-shaped bending edges 54; Figure 2-4 The arc-shaped bent edge 54 can adopt different structures. Since the part to be detected is in the gap between the two blades on the engine wheel, the detection sensor continues to detect through the narrow gap, so the overall structure of the detection sensor used is very fine. In this embodiment, the supporting spring piece 51 is an ultra-thin card-type spring piece. In order to facilitate the process production of fine structures, the structure of the arc-shaped bent edge 54 of the supporting spring piece 51 is preferably adopted as shown in the attached Figure 3 or attached Figure 4 In the structure shown, the edge teeth can be punched out first, and then the edge can be punched to form an arc-shaped bent edge. The arc-shaped bent edge 52 is the same as the supporting spring 51, and is made of elastic material, which has a certain structural buffering effect. At the same time, the arc-shaped edge makes the exterior of the sensor streamlined, which can overcome the vibration and instability caused by the assembly and processing errors between the blades and the wheel disc, and improve the accuracy and efficiency of the detection; at the same time, it reduces the relative resistance of the sensor during rotation detection, avoiding the detection sensor from getting stuck or being damaged.

[0036] 2) Installation of the detection sensor: The detection sensor described in step 1) is fixedly mounted on the side of the tenon of the engine blade to be tested and on the wheel disc;

[0037] 3) Implementation of detection: The engine turbine disc is slowly rotated by external force, so that the engine turbine disc and blades rotate one circle relative to the detection sensor. During this process, the detection sensor scans and obtains a high-definition array eddy current imaging image of the entire wheel disc and blade tenon.

[0038] Furthermore, in step 3), the working mode of the detection sensor is a high-frequency multi-frequency variable array excitation mode, and the high-frequency multi-frequency variable array excitation mode uses an excitation frequency range of 10kHz to 1MHz to excite the detection sensor, and is also a multi-frequency excitation and variable array detection. The use of high-frequency excitation can effectively obtain tiny cracks on the edge of the blade tenon or the wheel tenon groove. The use of multi-frequency excitation and variable array detection can further suppress the impact of the vibration caused by mechanical rotation on the detection results.

[0039] Furthermore, combined with a video probe, video image information of the complex and narrow space of the engine can be obtained, so as to quickly complete the surface defect detection of the entire wheel and blade tenon.

[0040] The present invention also discloses an overall structure of a detection probe. This embodiment is used to detect the inner side of the tenon between two adjacent blades on the engine. During the detection, the final path from the casing to the detection surface must pass through the narrow gap between the two blades, which is only 2mm-3mm. Figure 6 The structural schematic diagram of the detection probe shown in the figure includes a handle 60, a bent probe rod 70 and a detection sensor 50 of the present invention. The detection personnel holds the handle 60 and extends the bent probe rod 70 from the exploration hole reserved on the aircraft engine. The bent probe rod of the detection probe is pressed against the narrow gap between the two blades outside the tenon to be tested through the complex narrow space video image information obtained by the video probe. The detection sensor is extended from the narrow gap between the two blades and fixedly covered on the side of the tenon of the engine blade to be tested and the wheel disc, and the scanning imaging detection of the entire wheel disc and the blade tenon is completed according to the above-mentioned detection method.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A rapid in-situ detection method for aircraft engine wheel discs and blade tenons, characterized in that: The steps include: 1) Design of detection sensor: The detection sensor is an array eddy current detection sensor, which includes a supporting spring, a plurality of small-diameter cylindrical coils, and a micro-planar encoding disk. The plurality of small-diameter cylindrical coils are arranged in an array and embedded on the surface of the supporting spring sheet, and the side surfaces of the small-diameter cylindrical coils face the surface of the supporting spring sheet; The micro-plane encoding disk is embedded on the front end surface of the supporting spring sheet; Arc-shaped bending edges are arranged on both sides of the supporting spring sheet; 2) Installation of the detection sensor: The detection sensor described in step 1) is fixedly mounted on the side of the tenon of the engine blade to be tested and on the wheel disc; 3) Implementation of detection: The engine turbine disc is slowly rotated by external force, so that the engine turbine disc and blades rotate one circle relative to the detection sensor. During this process, the detection sensor scans and obtains a high-definition array eddy current imaging image of the entire wheel disc and blade tenon.

2. A rapid in-situ detection method for aircraft engine disks and blade tenons according to claim 1, characterized in that: Step 3) The working mode of the detection sensor is a high-frequency multi-frequency variable array excitation mode, and the high-frequency multi-frequency variable array excitation mode uses an excitation frequency range of 10kHz to 1MHz to excite the detection sensor, and is also multi-frequency excitation and variable array detection.

3. A rapid in-situ detection method for aircraft engine disks and blade tenons according to claim 2, characterized in that: Furthermore, combined with a video probe, video image information of the complex and narrow space of the engine can be obtained, so as to quickly complete the surface defect detection of the entire wheel and blade tenon.

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