A power plant blade tenon discontinuous in-situ eddy current detection probe and detection method

Abstract

The present application relates to the technical field of nondestructive testing, and especially to a power device blade tenon discontinuity in-situ eddy current testing probe and testing method, which comprises a handle, a telescopic probe rod and a detection assembly arranged at the end of the telescopic probe rod connected in sequence, the detection assembly comprises a hollow and telescopic micro protective shell, a flexible sheet rotatably arranged in the micro protective shell and capable of being placed in the tenon and mortise gap, an L-shaped skeleton provided with an eddy current testing coil, and an electromagnetic paddle arranged at the front end of the L-shaped skeleton to adjust the tenon and mortise gap by pushing the blade; during testing, the probe is pushed, the micro protective shell is compressed, the L-shaped skeleton is stretched out from the opening end of the micro protective shell and inserted into the gap between the tenon and mortise and adhered to the key position for testing. The present application has a simple overall structure, is easy to operate, has high reliability and practicability, and effectively realizes the in-situ testing of the key position discontinuity defect of the blade tenon.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of non-destructive testing, in particular to a power device blade tenon discontinuous in-situ eddy current detection probe and detection method. BACKGROUND

[0002] Modern aircraft, a large number of detachable blade and tenon groove engine structure. Because the aero-engine is in high temperature, high pressure, high speed working state, especially as a military use of warplanes, engine fast start, acceleration and various special maneuvering flight, resulting in blade fatigue damage and failure. In the aero-engine blade tenon tenon groove micro-connection structure, in order to make the dynamic balance of the engine running, there is a small gap between the blade and the tenon groove, which is the key stress part of the blade tenon and the tenon groove, which is prone to crack, and serious crack will produce local drop of blade tenon. Reference to the attached Figures 1a-1c In practice, it is found that the crack exists in the inner side of the blade tenon and the tenon groove at the initial stage of crack development, which cannot be detected from the outside, so the existing eddy current detection sensor cannot be found, and the crack is often detected after it develops to a certain extent or drops, which has great safety hidden danger. Similar situation also exists in gas turbine. Based on this, the present application studies a kind of in-situ eddy current detection sensor for the important stress part of the blade tenon in the micro-connection structure of the power device blade, which strives to solve the above problems. SUMMARY

[0003] To solve the above problems, the present application provides a kind of in-situ eddy current detection probe and detection method for power device blade tenon discontinuity, the present application is realized as follows:

[0004] An in-situ eddy current detection probe for power device blade tenon discontinuity is used for in-situ detection of the key part of the blade tenon in the micro-connection structure of the engine turbine rotor, the key part is on the tenon tenon groove contact surface near the blade part of the tenon, the in-situ eddy current detection probe is a fine probe matched with the tenon groove, including handle, telescopic probe rod and detection assembly arranged at the end of the telescopic probe rod connected in sequence, the detection assembly includes:

[0005] Micro protective shell, the micro protective shell is a telescopic structure with single end opening and hollow inside, the micro protective shell can be elastically telescopic along its axial direction;

[0006] L-shaped skeleton, the L-shaped skeleton is rotatably arranged in the micro protective shell, when the micro protective shell can be elastically telescopic along its axial direction, the L-shaped skeleton can be stretched out from its opening end, the L-shaped skeleton is a flexible sheet that can be placed in the gap between the tenon and the tenon groove, and the L-shaped skeleton is provided with an eddy current detection coil by using metal plating film technology; and,

[0007] An electromagnetic tab is arranged at the front end of the L-shaped skeleton and used to move the blade to adjust the gap between the tenon and the mortise;

[0008] During detection, the in-situ eddy current detection probe is inserted into the hole of the engine, when the in-situ eddy current detection probe is located in the detection area, the micro protective shell is abutted against the insertion edge of the blade and the mortise, the electromagnetic tab moves the blade to fix the gap between the tenon and the mortise, the L-shaped skeleton is extended from the opening end of the micro protective shell, the L-shaped skeleton is located at the stress fatigue key position to be detected, the probe is pushed, the micro protective shell is compressed and abutted against the insertion edge of the blade and the mortise, and the L-shaped skeleton is arranged in the gap between the tenon and the mortise and adheres to the stress fatigue key position for detection.

[0009] As a further improvement, the micro protective shell is a telescopic rubber tube or a telescopic spring, the maximum compression length of the micro protective shell is equal to the length of the L-shaped skeleton, the micro protective shell is fixedly arranged at the tail end of the telescopic probe, and the L-shaped skeleton is rotatably embedded in the middle part of the micro protective shell through a rotating shaft disc.

[0010] As a further improvement, an insulating protective film and a wear-resistant coating are further coated on the upper surface of the eddy current detection coil.

[0011] As a further improvement, the L-shaped skeleton is composed of a hollow frame structure of memory coils with supporting property, and a flexible thin sheet is clamped in the frame.

[0012] As a further improvement, the lower end of the micro protective shell is integrally provided with a positioning clamping block matched with the edge of the mortise.

[0013] As a further improvement, the detection assembly further comprises an endoscope assembly arranged at the upper end of the micro protective shell and away from the hole.

[0014] The application further discloses an in-situ eddy current detection method for a fatigue crack of a blade tenon of an aero-engine, and the in-situ eddy current detection probe is used for in-situ detection of a stress fatigue key position of a blade tenon of a micro-motion tenon joint structure in an engine turbine rotor, and detection steps are as follows.

[0015] A, probe positioning: the probe is inserted into the hole of the engine hole probe, the endoscope assembly feeds back the working condition in the engine in real time, the movement and insertion of the probe are carried out according to the feedback image of the endoscope assembly, when the probe is located in the detection area, the micro protective shell is abutted against the insertion edge of the blade and the mortise, the positioning clamp is fixedly clamped on the edge of the mortise, the electromagnetic paddle drives the blade to make the gap between the tenon and the mortise fixed, the L-shaped skeleton is stretched out of the opening end of the micro protective shell, and the L-shaped skeleton is located at the stress fatigue key position to be detected;

[0016] B, L-shaped skeleton adjustment: the different detection surfaces of the L-shaped skeleton in the normal position and the corresponding detection channels are numbered respectively, the horizontal direction corresponds to the first detection surface, the vertical direction corresponds to the first detection surface, the detection surfaces and the detection channels are switched to detect the stress fatigue key positions on the left and right sides of the blade tenon symmetrically;

[0017] C, push detection: push the probe, the micro protective shell is compressed and abutted against the insertion edge of the blade and the mortise, the L-shaped skeleton is pushed into the gap between the tenon and the mortise and adheres to the stress fatigue key position, the eddy current detection coil on the L-shaped skeleton is excited, and the detection signal is obtained.

[0018] Further, in step B, when the stress fatigue key position on the left side of the blade tenon is detected, the L-shaped skeleton in the normal position is used for detection, the first detection surface is used for horizontal direction stress fatigue key position detection, and the second detection surface is used for vertical direction stress fatigue key position detection.

[0019] When the stress fatigue key position on the right side of the blade tenon is detected, the L-shaped skeleton is rotated counterclockwise by 90 degrees, the second detection surface is used for horizontal direction stress fatigue key position detection, and the first detection surface is used for vertical direction stress fatigue key position detection.

[0020] Compared with the prior art, the present application can obtain the following technical effects:

[0021] 1. The present application can realize in-situ detection of the stress fatigue key position of the blade tenon under the micro-motion mortise joint structure under the complex hole probe condition, the detection position is moved to the detection area through the endoscope and the bending telescopic probe, further, the present application combines the structural characteristics of the blade tenon and the mortise, uses the small gap between the tenon and the mortise as the basis for the detection accessibility of the probe, designs an L-shaped ultra-thin skeleton, and uses metal plating film technology to set the eddy current detection coil, so that it can be placed in the gap between the tenon and the mortise and adhere to the stress fatigue key position of the tenon, and realize in-situ detection and effective detection of the stress fatigue crack of the blade tenon stress area.

[0022] 2、Further, the application sets a micro protective shell which can be elastically stretched, rotatably sleeved outside the L-shaped framework, protects the fine and small L-shaped ultra-thin framework, avoids damage of the detection sensor in the process of stretching into the complex engine structure, and the structure which can be elastically compressed and deformed does not interfere with the gap between the tenon and the mortise of the L-shaped ultra-thin framework, and simultaneously serves as a carrier for expanding the function of the detection probe structure of the application.

[0023] Further, the L-shaped ultra-thin framework and the micro protective shell can be rotatable relative to each other, the same probe can be used to detect the stress fatigue key parts on the left and right sides of the blade tenon, the practicability of the probe is improved, the probe does not need to be replaced, and the detection efficiency is improved.

[0024] 3、Further, the positioning block is arranged at the lower end of the micro protective shell to assist in positioning the probe, and the gap adjusting piece is arranged at the two sides of the micro protective shell to slightly push the blade, so that the gap between the blade tenon and the mortise on the detection side is kept fixed, the L-shaped ultra-thin framework is easily inserted, and the operation is convenient and efficient. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the application examples or the prior art or the descriptions in the prior art, it is obvious that other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0026] Figures 1a-1c It is a schematic diagram of the blade stress fatigue parts in different states.

[0027] Figure 2 It is a schematic diagram of the key parts of the blade prone to stress fatigue.

[0028] Figure 3 It is a schematic diagram of a blade disc structure.

[0029] Figure 4 It is a detection schematic diagram of the in-situ eddy current detection probe of the application.

[0030] Figure 5 It is a schematic diagram of the in-situ eddy current detection probe of the application. Figure 4

[0031] Figure 6 It is a schematic diagram of the in-situ eddy current detection probe of the application.

[0032] Figure 7 It is a schematic diagram of the micro protective shell compression structure of the in-situ eddy current detection probe.

[0033] Figure 8 It is a schematic diagram of the micro protective shell compression structure of the in-situ eddy current detection probe. Figure 7 ​Schematic diagram in another perspective view.

[0034] Figure 9 Schematic diagram of L-shaped skeleton rotation change of in-situ eddy current detection probe.

[0035] In the figure:

[0036] 10 - in-situ eddy current detection probe, 11 - handle, 12 - telescopic probe rod, 13 - detection assembly;

[0037] 131 - micro protective shell, 132 - L-shaped skeleton, 133 - eddy current detection coil, 134 - electromagnetic dial piece, 135 - positioning block, 136 - endoscope assembly;

[0038] 20 - blade, 21 - tenon;

[0039] 30 - mortise. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application.

[0041] There are a large number of tenon connection structures in the engine. In order to maintain dynamic balance, a small gap is reserved between the tenon connection structures. Especially in the extreme working environment of high temperature, high pressure and high speed such as aero-engine or gas turbine, such tenon connection structures generally have fretting damage. Commonly, the tenon head and mortise of the engine turbine rotor blade are connected in the form of fretting tenon. Through theoretical research and practice, it is found that the initiation or propagation point of fretting fatigue crack is generally located at the tooth part near the blade body of the tenon head. Referring to the attached Figure 2 Taking a multi-tooth tenon head mortise model as an example, the A area in the figure is the key part (L-shaped) where the blade is prone to stress fatigue. Since the initial crack initiation position is at the insertion part of the tenon head and mortise, the conventional eddy current detection sensor cannot find it. The present application studies the complex structure of the engine and the special structural features of the crack initiation position, and invents an in-situ eddy current detection sensor under extreme conditions of an aero-engine, with the following specific structure.

[0042] This embodiment takes aero-engine blade tenon detection as an example, referring to the attached Figures 3-9The application discloses an in-situ eddy current detection probe for a fatigue crack of an aero-engine blade tenon, and is used for in-situ detection of a stress fatigue key position of a blade tenon under a micro-joint tenon structure in an engine turbine rotor, wherein the stress fatigue key position is on a tenon groove contact surface of the tenon close to a blade body part, and the in-situ eddy current detection probe is a fine probe matched with the tenon groove, and comprises a handle 11, a telescopic probe rod 12 and a detection assembly arranged at the end of the telescopic probe rod 12 which are connected in sequence, and the telescopic probe rod 12 is designed as a bending structure which can freely extend into the engine blade, and is adapted to the complex engine internal structure.

[0043] The detection assembly 13 comprises a micro protective shell 131, an L-shaped skeleton 132 and an electromagnetic pusher 134.

[0044] The micro protective shell 131 is a telescopic structure with a single-end opening and an internal hollow, and can elastically extend and contract along the axial direction, and when detection is performed, the micro protective shell 131 abuts against the outer edge of the blade and the tenon groove, and when the probe is pushed, the micro protective shell 131 is compressed under stress; the elastically extendable and contractible micro protective shell protects the fine and small L-shaped ultrathin skeleton, so that the detection sensor is prevented from being damaged in the process of extending into the complex engine structure; the elastically compressible and deformable structure does not interfere with the gap between the tenon and the tenon groove, and simultaneously serves as a carrier for expanding the function of the detection probe structure of the application.

[0045] The L-shaped skeleton 132 is rotatably arranged in the micro protective shell 131, and when the micro protective shell 131 elastically extends and contracts along the axial direction, the L-shaped skeleton 132 can extend out of the opening end, the L-shaped skeleton 132 is a flexible sheet which can be arranged in the gap between the tenon and the tenon groove, and the eddy current detection coil 133 is arranged on the L-shaped skeleton 132 by using a metal plating film technology; the design of the L-shaped skeleton can better fit the blade tenon 103 to be detected, and effectively detect the side surface and the bottom surface of the blade tenon 103 which may have discontinuity at one time, and after one-time detection, the L-shaped skeleton does not need to be moved for scanning, so that the influences of edge effect and lift-off effect which may occur in the process of probe sliding scanning are avoided.

[0046] In order to solve the problem that the gap between the tenon and the tenon groove is not fixed and shakes on both sides, the electromagnetic pusher 134 is arranged at the front end of the L-shaped skeleton 132 and is used for pushing the blade to adjust the gap between the tenon and the tenon groove, so that the gap between the tenon and the tenon groove is in a fixed state, and the L-shaped detection structure can be inserted into the gap.

[0047] In the detection, the in-situ eddy current detection probe 10 is inserted into the hole of the engine, when the in-situ eddy current detection probe 10 is located in the detection area, the micro protective shell 131 is abutted to the insertion edge of the blade and the mortise, the electromagnetic switch 134 is below the gap edge or inserted into the gap, the electromagnetic switch 134 is connected, the electromagnetic switch 134 quickly drives the blade, the mortise and the gap are fixed, the probe is pushed, the micro protective shell 131 is compressed and abutted to the insertion edge of the blade and the mortise, the L-shaped skeleton 132 is extended from the opening end of the micro protective shell 131, is located in the stress fatigue key position to be detected, and is moved to be inserted into the gap of the mortise and abutted to the stress fatigue key position for detection.

[0048] The micro gap between the blade tenon and the mortise of the micro mortise joint of the aero-engine is ingeniously utilized, the ultra-thin eddy current detection structure is designed, and the in-situ eddy current detection of the stress area fatigue crack of the blade tenon is realized, so that the operation is convenient and the detection is efficient.

[0049] As a further improvement, the micro protective shell 131 is a telescopic rubber tube or a telescopic spring, the maximum compression length of the micro protective shell 131 is equal to the length of the L-shaped skeleton 132, that is, when the micro protective shell 131 is compressed to the maximum, the L-shaped skeleton 132 can be completely extended from the micro protective shell 131, and the compression amount can be used as a reference for the extension amount of the L-shaped skeleton, and the micro protective shell 131 can also be used as an auxiliary limiting.

[0050] Further, the micro protective shell 131 is fixedly arranged at the end of the telescopic probe rod 12, and the L-shaped skeleton 132 is rotatably embedded in the middle of the micro protective shell 131 through a rotating shaft disc, so that the same probe can be used to detect the stress fatigue key positions on the left and right sides of the blade tenon, the practicability of the probe is improved, the probe does not need to be replaced, and the detection efficiency is improved.

[0051] As a further improvement, since the mortise and the blade are both metal materials, in the embodiment, an insulating protective film and a wear-resistant coating are further plated on the upper surface of the eddy current detection coil 133.

[0052] Since the gap to be detected is small, the L-shaped skeleton needs to have certain support when being inserted into the gap, and also needs to have certain flexibility to prevent extrusion damage, in the embodiment, the L-shaped skeleton 132 is spliced into a hollow frame structure by a supporting memory coil, and a flexible sheet is clamped in the frame; in the embodiment, the L-shaped skeleton 132 is finely designed, and the thickness is 0.1-0.2 mm, so that the L-shaped skeleton can be inserted into the small gap between the mortise and the mortise. Further, the electromagnetic switch 134 is integrally embedded on the frame structure at the front end of the L-shaped skeleton 132, and the edge of the electromagnetic switch 134 is designed in a wedge shape to facilitate the introduction into the small gap.

[0053] Further improved, the lower end of the micro protective shell 131 is integrally provided with a positioning block 135 matched with the edge of the mortise and tenon 30. The detection site can be quickly positioned and limited by the positioning block.

[0054] Further improved, the detection assembly 13 further comprises an endoscope assembly 136 arranged at the upper end of the micro protective shell 131 and away from the opening. The endoscope assembly feeds back real-time images to assist the movement of the probe.

[0055] The application also discloses an in-situ fine eddy current detection method for a discontinuous tenon head of a motive device blade, which adopts the in-situ eddy current detection probe to detect the key part of the tenon head of the lower blade of the micro-motion mortise and tenon structure in the engine turbine rotor, and comprises the following detection steps:

[0056] A, probe positioning: the probe is inserted into the hole of the engine, the endoscope assembly feeds back the working condition in the engine in real time, the movement and insertion of the probe are conducted according to the feedback images of the endoscope assembly, when the probe is located in the detection area, the micro protective shell is abutted against the insertion edge of the blade and the mortise and tenon, the positioning block is fixedly clamped on the edge of the mortise and tenon, the electromagnetic paddle drives the blade to fix the gap between the tenon head and the mortise and tenon, the L-shaped framework is stretched out of the opening end of the micro protective shell, and the L-shaped framework is located at the stress fatigue key part to be detected;

[0057] B, L-shaped framework adjustment: different detection surfaces of the L-shaped framework in the normal position and corresponding detection channels are numbered respectively, the horizontal direction corresponds to the first detection surface, and the vertical direction corresponds to the first detection surface; the detection surfaces and the detection channels are switched to detect the stress fatigue key parts on the left side and the right side of the blade tenon symmetrically;

[0058] C, pushing detection: the probe is pushed, the micro protective shell is compressed and abutted against the insertion edge of the blade and the mortise and tenon, the L-shaped framework is pushed into the gap between the tenon head and the mortise and tenon and adheres to the stress fatigue key part, the eddy current detection coil on the L-shaped framework is excited, and the detection signal is acquired. Further, in order to better distinguish the defect signal, a mixed frequency can also be used to suppress the interference signal.

[0059] Further, in step B, when the stress fatigue key parts on the left side of the blade tenon head are detected, the L-shaped framework in the normal position is used for detection, the first detection surface is used for horizontal direction stress fatigue key part detection, and the second detection surface is used for vertical direction stress fatigue key part detection.

[0060] When the stress fatigue key position on the right side of the blade tenon is detected, the L-shaped skeleton is rotated counterclockwise by 90°, the second detection surface is used to detect the stress fatigue key position in the horizontal direction, and the first detection surface is used to detect the stress fatigue key position in the vertical direction.

[0061] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A power plant blade tenon discontinuity in-situ eddy current detection probe, used for in-situ detection of key parts of blade tenon in micro-motion tenon joint structure of engine turbine rotor, the key parts are on the tenon groove contact surface of the tenon near the blade body part, the in-situ eddy current detection probe is a fine probe matched with the tenon groove, comprising a handle, a telescopic probe rod and a detection assembly arranged at the end of the telescopic probe rod connected in sequence, characterized in that, The detection assembly comprises: A micro protective shell, which is a telescopic structure with a single open end and an internal hollow, and can elastically expand and contract in the axial direction thereof; An L-shaped skeleton, which is rotatably arranged in the internal hollow of the micro protective shell, and can extend from the open end of the micro protective shell when the micro protective shell elastically expands and contracts in the axial direction thereof, and is a flexible sheet that can be inserted into the gap between the tenon and the mortise, and a vortex detection coil is arranged on the flexible sheet; An electromagnetic tab, which is arranged at the front end of the L-shaped skeleton, and is used for automatically moving the blade to adjust the gap between the tenon and the mortise; During detection, the in-situ vortex detection probe is inserted into the probe hole of the engine, and when the in-situ vortex detection probe is located in the detection area, the micro protective shell is abutted against the joint edge of the blade and the mortise, the electromagnetic tab moves the blade to fix the gap between the tenon and the mortise, the L-shaped skeleton extends from the open end of the micro protective shell, the L-shaped skeleton is located at the stress fatigue key position to be detected, the probe is pushed, the micro protective shell is compressed and abutted against the joint edge of the blade and the mortise, and the L-shaped skeleton is arranged in the gap between the tenon and the mortise and adheres to the stress fatigue key position to perform detection.

2. A probe for in-situ eddy current inspection of a blade tenon discontinuity of a power plant according to claim 1, characterized in that, The micro protective shell is a telescopic rubber tube or a telescopic spring, the maximum compression length of the micro protective shell is equal to the length of the L-shaped skeleton, the micro protective shell is fixedly arranged at the end of the telescopic probe rod, and the L-shaped skeleton is rotatably embedded in the middle of the micro protective shell through a rotating shaft disc.

3. A probe for in-situ eddy current inspection of a blade tenon discontinuity of a power plant according to claim 1, wherein, An insulating protective film and a wear-resistant coating are further coated on the upper surface of the vortex detection coil.

4. A probe for in-situ eddy current inspection of a blade tenon discontinuity of a power plant according to claim 1, wherein, The L-shaped skeleton is composed of hollow frame structures of memory coils with supporting properties, and a flexible sheet is clamped in the frame; the electromagnetic tab is integrally embedded on the frame structure at the front end of the L-shaped skeleton, and the edge of the electromagnetic tab is designed in a wedge shape.

5. A power plant blade tenon discontinuity in-situ eddy current inspection probe according to claim 1, wherein, A positioning clamping block that is matched with the edge of the mortise is integrally arranged at the end close to the opening of the lower end of the micro protective shell.

6. A power plant blade tenon discontinuity in-situ eddy current inspection probe according to claim 5, wherein, The detection assembly further comprises a endoscope assembly, which is arranged at the upper end of the micro protective shell and away from the opening.

7. A method for in-situ eddy current testing of the discontinuity of the blade tenon of a power plant, using the in-situ eddy current testing probe of claim 6 to conduct in-situ testing of the key points of the blade tenon under the micro-motion tenon joint structure in the engine turbine rotor, characterized in that, The detection steps comprise: A. Probe positioning: the probe is inserted into the probe hole of the engine, the endoscope assembly feeds back the working conditions in the engine in real time, the probe is moved and inserted according to the feedback image of the endoscope assembly, when the probe is located in the detection area, the micro protective shell is abutted against the joint edge of the blade and the mortise, the positioning clamping block is fixedly clamped on the edge of the mortise, the electromagnetic tab moves the blade to fix the gap between the tenon and the mortise, the L-shaped skeleton extends from the open end of the micro protective shell, and the L-shaped skeleton is located at the stress fatigue key position to be detected; B. L-shaped skeleton adjustment: different detection surfaces of the L-shaped skeleton in the normal position and corresponding detection channels are numbered, the horizontal direction corresponds to the first detection surface, and the vertical direction corresponds to the second detection surface; the stress fatigue key positions on the left and right sides of the blade tenon are detected by switching the detection surface and the detection channel. C. Push detection: push the probe, the micro protective shell is compressed against the joint edge of the blade and the mortise, the L-shaped skeleton is pushed into the gap of the tenon mortise and fits the stress fatigue key position, the eddy current detection coil on the L-shaped skeleton is excited, and the detection signal is obtained.

8. A method of in-situ eddy current inspection of a blade tenon discontinuity of a power plant according to claim 7, characterised in that, In step B, when detecting the stress fatigue key position on the left side of the blade tenon, the L-shaped skeleton in the normal position is used for detection, the first detection surface is used for detecting the stress fatigue key position in the horizontal direction, and the second detection surface is used for detecting the stress fatigue key position in the vertical direction. When detecting the stress fatigue key position on the right side of the blade tenon, the L-shaped skeleton is rotated counterclockwise by 90 degrees, the second detection surface is used for detecting the stress fatigue key position in the horizontal direction, and the first detection surface is used for detecting the stress fatigue key position in the vertical direction.

Images