Gas turbine turbine wheel disk blade root groove array vortex probe scanning mechanism and method

Abstract

The application discloses a gas turbine turbine disc blade root groove array eddy current probe scanning mechanism and method, which comprises a probe framework, a driving module, a clamping device and a detection module. The probe framework is stably installed and fixed with the detected turbine disc blade root groove, and provides structural support for the driving module and the detection module, avoiding direct contact and friction between the array eddy current coil and the turbine disc blade root groove. The driving module and the clamping device provide high-resolution positioning accuracy and stable scanning speed for the array eddy current coil, improving the detection sensitivity and quantitative accuracy of the array eddy current detection. The detection module provides an arrangement surface suitable for the shape of the turbine disc blade root groove for the array eddy current coil, and realizes stable and efficient scanning through the clamping device and the driving device. Finally, the problems of high labor intensity, low array eddy current detection efficiency and low accuracy caused by uneven scanning speed, unstable lift-off and inaccurate probe positioning in the traditional array eddy current detection of the in-service turbine disc blade root groove are solved.

Description

Technical Field

[0001] This invention belongs to the field of non-destructive testing of gas turbine components, specifically relating to a scanning mechanism and method for an eddy current probe of a gas turbine disk blade root groove array. Background Technology

[0002] In rotating machinery such as gas turbines, the turbine disk blade root groove is one of the key components, and its quality and integrity directly affect the safety of the entire machine. Therefore, regular inspection of the blade root groove and timely detection and handling of potential defects are of great significance for ensuring the stable operation of the unit.

[0003] Array eddy current testing (ADC) technology, as a high-precision and high-sensitivity non-destructive testing method, has been widely used in the inspection of turbine blade root grooves. However, traditional ADC testing generally involves manual scanning by inspectors sliding the array eddy current probe, which is not only labor-intensive but also prone to problems such as uneven scanning speed (stuttering), unstable lifting, and inaccurate probe positioning caused by rust, grease, pits, etc. on the turbine blade root groove surface.

[0004] To overcome the problems existing in the prior art, a scanning mechanism and method for an eddy current probe array of turbine disk blade root grooves for gas turbines is proposed. This ensures uniform speed and stability during the scanning process and accurate positioning of the probe, thereby improving the detection efficiency and accuracy of turbine disk blade root grooves. Summary of the Invention

[0005] The purpose of this invention is to provide a scanning mechanism and method for an array eddy current probe in the root groove of a gas turbine disk, aiming to solve the problems of high labor intensity and low efficiency and accuracy of array eddy current detection caused by uneven scanning speed, unstable lifting, and inaccurate probe positioning in traditional array eddy current detection of the root groove of in-service turbine disks.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A scanning mechanism for an eddy current probe of a gas turbine disk blade root groove array includes a probe frame, a drive module, a detection module, and a clamping device;

[0008] The probe frame includes a frame body, a drive module mounting interface, an eddy current coil communication interface, and a sliding contact conductive slide rail. The frame body has a hollow structure. The drive module mounting interfaces are located at both ends of the frame body along the axial direction, and both ends are machined with drive motor mounting holes and linear guide rail mounting holes. The eddy current coil communication interface is located on the end face of the frame body and is used to connect to the array eddy current detector. The sliding contact conductive slide rail is installed axially in the probe frame body, with one end covered by insulating material and the other end connected to the eddy current coil communication interface.

[0009] The drive module includes a drive motor, a transmission belt, and a linear guide assembly. There are two drive motors, which are respectively installed at both ends of the probe frame body. The transmission belt is sleeved on the two drive motor drive pulleys, and the drive motor drives the transmission belt to move along the axis by rotating. There are two linear guide assemblies, in which the guide base is installed in the probe frame body through the linear guide mounting holes, located directly above and directly below the transmission belt.

[0010] The detection module includes a profiling body, an array of eddy current coils, and a conductive slider. The profiling body's detection surface is completely fitted with the inner surface of the probe skeleton body, and the axial width of the profiling body is greater than the width of the array of eddy current coils. The array of eddy current coils are arranged on the profiling body's detection surface. The conductive slider is installed on the upper surface of the profiling body, connected to the array of eddy current coils via a cable, and engages with a sliding contact conductive rail to transmit the array of eddy current coil signals.

[0011] The clamping device is used to press against the drive belt, thereby controlling the movement of the detection module.

[0012] A further improvement of this invention is that the clamping device includes a pressure plate, multiple guide posts, multiple springs, an electromagnet, and a pressure head; the pressure plate has two pieces, the lower pressure plate is connected to the contoured body and has multiple guide holes machined on it, and the upper pressure plate has the same number and size of guide holes machined at corresponding positions; the multiple guide posts pass through the corresponding guide holes of the upper and lower pressure plates respectively, and multiple springs are sleeved between the upper and lower pressure plates of the multiple guide posts; the upper and lower surfaces of the multiple springs are in contact with the lower surface of the upper pressure plate and the upper surface of the lower pressure plate respectively; the electromagnet is integrated on the upper pressure plate and is located at the geometric center of the multiple guide holes of the upper pressure plate; the pressure head is located on the lower surface of the upper pressure plate and the upper surface of the lower pressure plate respectively, and the pressing state with the transmission belt is controlled by the on and off state of the electromagnet, thereby controlling the movement of the detection module.

[0013] A further improvement of the present invention is that the thickness of the contact area between the probe skeleton body and the contour detection surface is no more than 2mm, and it is made of high-strength engineering plastic.

[0014] A further improvement of the present invention is that the axial distance between the center of the drive motor mounting hole and the end face of the turbine disk blade root groove is greater than the sum of the axial width of the contour body and the radius of the drive motor transmission wheel;

[0015] The axial distance between the center of the linear guide mounting hole and the end face of the turbine blade root groove is greater than the axial distance between the center of the drive motor mounting hole and the motor itself.

[0016] A further improvement of the present invention is that the contact surface between the sliding contact conductive slide rail and the conductive slider is covered with a layer of wear-resistant, low-resistance, and low-resistance material; and the interface between the sliding contact conductive slide rail and the conductive slider is shielded.

[0017] A further improvement of the present invention is that the drive motor is a micro-stepping motor with forward and reverse rotation functions, and the motor shaft is perpendicular to the axial center plane of the turbine disk blade root groove.

[0018] The diameter of the drive motor transmission wheel is not less than twice the sum of the thickness of the lower pressure plate and the pressure head.

[0019] A further improvement of the present invention is that the transmission belt is a flat belt with wear-resistant and anti-slip material layers on the upper and lower surfaces, and the thickness of the transmission belt is at least less than the gap between the upper pressure plate head and the lower pressure plate head in the unpressed state.

[0020] A further improvement of the present invention is that the length of the arc surface of the detection surface of the contoured body is not less than the length of the arc surface of the cross section of the turbine disk blade root groove, and the array of eddy current coils arranged on it is the same length as the arc surface of the detection surface.

[0021] A further improvement of the present invention is that the arrayed eddy current coils are arranged in two rows in an alternating manner, and a time-division multiple excitation transmission and reception method is used for excitation and reception;

[0022] The array of eddy current coils is arranged near the surface of the profiling detection surface to prevent damage caused by friction on the inner surface of the skeleton body during the detection process.

[0023] A method for scanning gas turbine disk blade root groove array eddy current probes, the method being based on the aforementioned gas turbine disk blade root groove array eddy current probe scanning mechanism, comprising:

[0024] The probe frame body is stably placed in the root groove of the turbine disk blade under test, so that the distances between the two ends of the frame body and the end faces of the root groove of the turbine disk blade under test are equal, ensuring that the array eddy current coil can completely scan the root groove of the turbine disk blade under test axially.

[0025] When the electromagnet is energized, the pressure plate is pressed onto the transmission belt. When the drive motor drives the transmission belt to move axially, the contoured body moves axially along the guide rail base through the slider by means of the driving force transmitted by the pressure plate. The conductive slider and the sliding contact conductive rail combine to transmit the excitation and reception signals of the array eddy current coil, and transmit the excitation and reception commands of the array eddy current detector to the array eddy current coil on the contoured body.

[0026] The drive motor records and transmits the scanning position and distance of the contoured object in real time, and the array eddy current detector generates a C-scan image to achieve uniform and stable scanning of the turbine disk blade root groove.

[0027] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0028] This invention provides a scanning mechanism and method for an array eddy current probe in the root groove of a gas turbine disk blade. The probe frame is stably installed and fixed to the root groove of the turbine disk blade being detected, and provides structural support for the drive module, detection module, etc., avoiding direct contact and friction between the array eddy current coil and the root groove of the turbine disk blade, thus ensuring the lifting stability and service life of the array eddy current coil. The drive module and clamping device provide the array eddy current coil with high-resolution positioning accuracy and stable scanning speed, improving the detection sensitivity and quantitative accuracy of array eddy current detection. The detection module provides an arrangement surface suitable for the shape of the turbine disk blade root groove for the array eddy current coil, and at the same time, the clamping device and drive device achieve stable and efficient scanning. Ultimately, this ensures uniform, stable, and efficient array eddy current scanning of the turbine disk blade root groove. Attached Figure Description

[0029] Figure 1 This is an isometric schematic diagram of an eddy current probe scanning mechanism for a gas turbine disk blade root groove array according to the present invention;

[0030] Figure 2 This is a side view schematic diagram of an eddy current probe scanning mechanism for a gas turbine disk blade root groove array according to the present invention;

[0031] Figure 3 This is a side view schematic diagram of the clamping device of the eddy current probe scanning mechanism for the root groove array of a gas turbine disk blade according to the present invention;

[0032] Figure 4 This is a schematic flowchart of a method for scanning a gas turbine disk blade root groove array eddy current probe according to the present invention.

[0033] Explanation of reference numerals in the attached figures:

[0034] 1-Probe skeleton, 11-Skeleton body, 12-Drive module mounting interface, 121-Drive motor mounting hole, 122-Linear guide rail mounting hole, 13-Eddy current coil communication interface, 14-Sliding contact conductive slide rail, 2-Drive module, 21-Drive motor, 22-Transmission belt, 23-Linear guide rail assembly, 231-Guide rail base, 232-Slider, 3-Detection module, 31-Following body, 32-Arrayed eddy current coil, 33-Conductive slider, 4-Clamping device, 41-Pressure plate, 411-Lower plate pressure plate, 412-Upper plate pressure plate, 42-Guide post, 43-Spring, 44-Electromagnet, 45-Pressure head, 5-Arrayed eddy current detector. Detailed Implementation

[0035] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0036] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0037] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0038] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0040] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0041] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0042] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0043] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0044] Example 1

[0045] like Figures 1-3 As shown, the present invention provides a scanning mechanism for an eddy current probe of a gas turbine disk blade root groove array, including a probe frame 1, a drive module 2, a detection module 3 and a clamping device 4.

[0046] The probe frame 1 includes a frame body 11, a drive module mounting interface 12, an eddy current coil communication interface 13, and a sliding contact conductive rail 14. The frame body 11 is a hollow structure, its cross-sectional dimensions perfectly matching the cross-sectional dimensions of the turbine blade root groove being tested, and its axial length is greater than the axial length of the turbine blade root groove. The drive module mounting interface 12 is located at both ends of the frame body 11 along its axial direction, with drive motor mounting holes 121 and linear guide rail mounting holes 122 machined at both ends. The eddy current coil communication interface 13 is located on the end face of the frame body 11 and is used to connect to the array eddy current detector 5, transmitting the detection signal from the array eddy current coil 32 to the array eddy current detector 5, and simultaneously transmitting the excitation and reception commands from the array eddy current detector 5 to the array eddy current coil 32. The sliding contact conductive rail 14 is installed axially within the probe frame body 11, one end covered with insulating material, and the other end connected to the eddy current coil communication interface 13.

[0047] The drive module 2 includes a drive motor 21, a transmission belt 22, and a linear guide assembly 23. Typically, there are two drive motors 21, mounted at opposite ends of the probe frame body 11 along the axial direction. The transmission belt 22 is fitted onto the drive pulleys of the two drive motors 21, and the drive motors 21 rotate to drive the transmission belts 22 axially. There are typically two linear guide assemblies 23, with guide bases 231 mounted in the probe frame body 11 through linear guide mounting holes 122, located directly above and below the transmission belts 22.

[0048] The detection module 3 includes a contoured body 31, an arrayed eddy current coil 32, and a conductive slider 33. The detection surface of the contoured body 31 is completely fitted to the inner surface of the probe frame body 11, and the axial width of the contoured body 31 is greater than the width of the arrayed eddy current coil 32. The arrayed eddy current coil 32 is arranged on the detection surface of the contoured body 31. The conductive slider 33 is mounted on the upper surface of the contoured body 31, connected to the arrayed eddy current coil 32 via a cable, and engages with a sliding contact conductive rail 14 to transmit signals from the arrayed eddy current coil 32.

[0049] The clamping device is used to press against the drive belt, thereby controlling the movement of the detection module.

[0050] In some embodiments, the clamping device 4 includes a pressure plate 41, a plurality of guide posts 42, a plurality of springs 43, an electromagnet 44, and a pressure head 45. The pressure plate 41 consists of two pieces. The lower pressure plate 411 is connected to the contour body 31 and has multiple guide holes machined on it. The upper pressure plate 412 has the same number and size of guide holes machined at corresponding positions. Multiple guide posts 42 pass through the corresponding guide holes of the upper pressure plate 412 and the lower pressure plate 411, and multiple springs 43 are sleeved between the upper and lower pressure plates of the multiple guide posts 42. The upper and lower surfaces of the multiple springs 43 are in contact with the lower surface of the upper pressure plate 412 and the upper surface of the lower pressure plate 411, respectively. An electromagnet 44 is integrated on the upper pressure plate 412 and is located at the geometric center of the multiple guide holes of the upper pressure plate 412. The pressure head 45 is located on the lower surface of the upper pressure plate 412 and the upper surface of the lower pressure plate 411, respectively. The pressure state of the electromagnet 44 with the transmission belt 22 is controlled by the on and off state of the electromagnet 44, thereby controlling the movement of the detection module 3.

[0051] In some embodiments, the thickness of the contact area between the probe skeleton body 11 and the detection surface of the contour body 31 is no more than 2 mm and is made of high-strength engineering plastic, thereby controlling the lift-off distance of the array eddy current probe within a range that does not significantly affect the detection effect, while ensuring the rigidity of the probe skeleton body 11 itself.

[0052] Preferably, the engineering plastic of the probe skeleton body 11 is ABS engineering plastic or polypropylene engineering plastic.

[0053] In some embodiments, the axial distance between the center of the drive motor mounting hole 121 and the end face of the turbine disk blade root groove is greater than the sum of the axial width of the contour body 31 and the radius of the drive motor 21 transmission wheel, so that the array eddy current coil 32 can scan outside the surface of the turbine disk blade root groove, ensuring that the array eddy current coil 32 covers 100% of the axial direction of the turbine disk blade root groove.

[0054] In some embodiments, the axial distance between the center of the linear guide mounting hole 122 and the end face of the turbine blade root groove is greater than the axial distance between the center of the drive motor mounting hole 121 and the drive motor mounting hole 121, ensuring that the scanning range of the contour body 31 is not limited by the linear guide assembly 23.

[0055] In some embodiments, the sliding contact conductive rail 14 is made of a material with good conductivity, wear resistance, and corrosion resistance, and its cross-sectional shape and size are matched with the eddy current coil communication interface 13, thereby improving the transmission stability of the array eddy current detection signal.

[0056] Preferably, the material of the sliding contact conductive rail 14 can be copper, silver, or gold-plated alloy materials.

[0057] In some embodiments, there is a suitable contact pressure between the sliding contact conductive rail 14 and the conductive slider 33 to ensure stable contact during movement.

[0058] In some embodiments, the contact surface between the sliding contact conductive rail 14 and the conductive slider 33 is covered with a layer of wear-resistant, low-resistance, and low-resistance material, which reduces friction and wear and maintains stable signal transmission.

[0059] Preferably, the contact surface between the sliding contact conductive rail 14 and the conductive slider 33 is selected by means of a gold plating layer or a carbon brush.

[0060] In some embodiments, a shielding layer is provided at the interface between the sliding contact conductive rail 14 and the conductive slider 33 to avoid the influence of external electromagnetic interference on the detection signal.

[0061] In some embodiments, the connecting cable between the conductive slider 33 and the array eddy current coil 32 is a wear-resistant and tensile-resistant flexible cable, and the cable should not be excessively stretched or twisted during the movement of the conductive slider 33, thus ensuring a stable connection for signal transmission between the array eddy current coil 32 and the conductive slider 33.

[0062] In some embodiments, the drive motor 21 is a micro-stepping motor with forward and reverse rotation functions. The motor shaft is perpendicular to the axial center plane of the turbine disk blade root groove, which ensures the stability of the array eddy current scanning speed, improves the positioning accuracy and defect quantitative accuracy of the array eddy current coil 32, and realizes the function of reciprocating scanning.

[0063] In some embodiments, the diameter of the drive motor 21 transmission wheel is not less than twice the sum of the thickness of the lower platen 411 and the pressure head 45, in order to prevent friction between the lower platen 411 and the transmission belt 22, which would cause wear and affect the operational stability of the scanning mechanism.

[0064] Preferably, the pressing head of the upper pressing plate 412 and the pressing head of the lower pressing plate 411 have the same thickness.

[0065] In some embodiments, the drive motor 21 transmission wheel has good strength and rigidity, and has appropriate tension and good friction between the contact surface with the transmission belt 22, thus avoiding unstable transmission, belt slippage and excessive wear.

[0066] In some embodiments, the transmission belt 22 is a flat belt with wear-resistant and anti-slip material layers on its upper and lower surfaces. The thickness of the transmission belt 22 is at least less than the gap between the upper pressure plate 412 pressure head 45 and the lower pressure plate 411 pressure head 45 in the unpressed state, thereby increasing the friction between the transmission belt 22 and the pressure head 45 during transmission and preventing wear caused by friction between the pressure head and the belt.

[0067] In some embodiments, the linear guide assembly 23 includes a guide base 231 and a slider 232. The guide base 231 is made of aluminum alloy with high strength and rigidity and low density. The slider 232 is a ball-type slider that can reduce friction and improve motion accuracy, thereby reducing the weight of the scanning mechanism and improving the accuracy and flexibility of the scanning process.

[0068] In some embodiments, the two guide rail bases 231 are installed in a direction parallel to the axis of the skeleton body 11, and the two sliders 232 are connected to the contour body 31, which ensures the parallelism between the contour body 31 and the skeleton body 11 during the scanning process, and avoids friction between them affecting the scanning speed or even damaging the array eddy current coil 32.

[0069] In some embodiments, the length of the arc surface of the probe 31 is not less than the length of the arc surface of the turbine blade root groove cross section, and the array eddy current coil 32 arranged on it is the same length as the arc surface of the probe, so that the array eddy current coil 32 can scan the entire cross section of the turbine blade root groove, ensuring that the array eddy current coil covers 100% of the cross section of the turbine blade root groove.

[0070] In some implementations, the arrayed eddy current coils 32 are arranged in two staggered rows, and a time-division multiple excitation transmission and reception method is used for excitation and reception, which reduces the possibility of missed defect detection and ensures the effective detection of defects with different orientations.

[0071] Preferably, the center distance of the arrayed eddy current coils 32 is no greater than 4 times the minimum length of the defect to be detected.

[0072] In some embodiments, the arrayed eddy current coils 32 are arranged near the detection surface of the contour body 31 to prevent damage caused by friction on the inner surface of the skeleton body 11 during the detection process.

[0073] Preferably, the distance between the arrayed eddy current coil 32 and the detection surface of the contour body 31 is 0.2mm to 0.5mm.

[0074] In some embodiments, the gap between the pressure head 45 of the lower platen 411 and the upper surface of the transmission belt 22 is between 0.1 mm and 0.2 mm. This reduces the impact on the transmission belt 22 when the pressure platen 41 is pressed, while avoiding friction between the pressure head 45 and the transmission belt 22.

[0075] In some embodiments, a guide pin is machined inside the guide through hole of the pressure plate 41, which cooperates with the guide groove on the guide post 42 to improve the guiding accuracy and reduce the sliding resistance.

[0076] Preferably, there are three guide posts 42 and three springs 43.

[0077] In some embodiments, the pressure head 45 is made of a non-slip material with a certain degree of elasticity and toughness, such as rubber or polyurethane, which increases the friction between the pressure head 45 and the transmission belt 22 during transmission.

[0078] Example 2

[0079] like Figure 4 As shown, the present invention provides a method for scanning the root groove array of a gas turbine disk blade using an eddy current probe, comprising the following steps:

[0080] Step S1: Place the probe frame body 11 stably in the root groove of the turbine disk blade to be tested, so that the distances from the two ends of the frame body 11 to the end face of the root groove of the turbine disk blade to be tested are equal, so as to ensure that the array eddy current coil 32 can completely scan the root groove of the turbine disk blade to be tested axially.

[0081] Step S2: When the electromagnet 44 is energized, the pressure plate 41 is pressed onto the transmission belt 22. When the drive motor 21 drives the transmission belt 22 to move axially, the contour body 31 moves axially along the guide rail base 231 through the slider 232 with the driving force transmitted by the pressure plate 41. The conductive slider 33 and the sliding contact conductive slide rail 14 are combined to transmit the excitation and reception signals of the array eddy current coil 32, and transmit the excitation and reception commands of the array eddy current detector 5 to the array eddy current coil 32 on the contour body 31.

[0082] Step S3: Drive motor 21 records and transmits the scanning position and distance of the contour body 31 in real time, and generates C-scan images through array eddy current detector 5 to achieve uniform and stable scanning of turbine disk blade root grooves.

[0083] Example 3

[0084] 1. Assemble the probe frame

[0085] The hollow probe skeleton body 11 is fabricated with a hollow part thickness of no more than 2mm. It is made of high-strength engineering plastic, and its cross-sectional dimensions are completely consistent with the cross-sectional dimensions of the turbine disk blade root groove under test. Its axial length is greater than the axial length of the turbine disk blade root groove.

[0086] Drive motor mounting holes 121 and linear guide mounting holes 122 are machined at both ends of the skeleton body 11. The axial distance between the center of the drive motor mounting hole 121 and the end face of the turbine blade root groove is greater than the sum of the axial width of the contour body 31 and the radius of the drive motor 21 transmission wheel. The axial distance between the center of the linear guide mounting hole 122 and the end face of the turbine blade root groove is greater than the axial distance between the center of the drive motor mounting hole 121 and the linear guide mounting hole 122.

[0087] An eddy current coil communication interface 13 is provided on the end face of the skeleton body 11 for connecting the array eddy current detector 5.

[0088] The sliding contact conductive slide rail 14 is installed, with one end covered by insulating material and the other end connected to the eddy current coil communication interface 13. Its cross-sectional shape and size match the eddy current coil communication interface 13.

[0089] 2. Install the driver module

[0090] One micro-stepping drive motor 21 with forward and reverse rotation function is installed at each of the two ends of the probe frame body 11. The diameter of the drive wheel of the drive motor 21 is not less than twice the sum of the thickness of the lower platen 411 and the pressure head 45.

[0091] Install the flat belt type transmission belt 22 and ensure that it is fitted onto the transmission wheel of the drive motor 21. The drive motor 21 drives the transmission belt 22 to move axially by rotating. The upper and lower surfaces of the transmission belt 22 are provided with wear-resistant and anti-slip material layers, the thickness of which is at least less than the gap between the upper plate pressure plate 412 pressure head 45 and the lower plate pressure plate 411 pressure head 45 in the unpressed state.

[0092] The linear guide rail assembly 23 is typically installed in two sets, located directly above and below the transmission belt 22, respectively. Two guide rail bases 231 are fixed in the probe frame body 11 through the linear guide rail mounting holes 122, with the installation direction parallel to the axis of the frame body 11. Two sliders 232 are ball-bearing sliders and are connected to the contour body 31.

[0093] 3. Assemble the testing module

[0094] Fabricate a shape-imitating body 31 to ensure that its detection surface is completely fitted to the inner surface of the probe skeleton body 11. The axial width of the shape-imitating body 31 is greater than the width of the array eddy current coil 32, and the arc length of the detection surface is not less than the arc length of the cross-section of the turbine disk blade root groove.

[0095] Two rows of staggered arrayed eddy current coils 32 are arranged near the surface of the detection surface of the profilotype 31, with a distance of 0.2 mm to 0.5 mm from the surface.

[0096] A conductive slider 33 is installed on the upper surface of the contour body 31, and it is ensured that it is connected to the array eddy current coil 32 via a cable and engages with the sliding contact conductive slide rail 14.

[0097] 4. Install clamping device

[0098] The mounting plate 41 is connected to the contour body 31 and has three guide holes with guide pins. The upper plate 412 has three guide holes of the same size with guide pins at the corresponding positions.

[0099] Install guide posts 42 and springs 43. The three guide posts 42 with guide grooves pass through the corresponding guide through holes of the upper pressure plate 412 and the lower pressure plate 411 respectively, and three springs 43 are fitted between the upper and lower pressure plates of the three guide posts 42. The upper and lower surfaces of the three springs 43 are in contact with the lower surface of the upper pressure plate 412 and the upper surface of the lower pressure plate 411 respectively.

[0100] Install an electromagnet 44 on the upper pressure plate 412 and ensure that it is located at the geometric center of the three guide holes of the upper pressure plate 412.

[0101] A pressure head 45 is installed on the lower surface of the upper pressure plate 412 and the upper surface of the lower pressure plate 411. The pressing state with the transmission belt 22 is controlled by the switching on and off of an electromagnet 44. The gap between the pressure head 45 and the upper and lower surfaces of the transmission belt 22 is between 0.1 mm and 0.2 mm.

[0102] 5. Scanning Method

[0103] The probe frame body 11 is stably placed in the root groove of the turbine disk blade under test, so that the distances from the two ends of the frame body 11 to the end face of the root groove of the turbine disk blade under test are equal, ensuring that the array eddy current coil 32 can completely scan the root groove of the turbine disk blade under test axially.

[0104] When the electromagnet 44 is energized, the pressure plate 41 is pressed onto the transmission belt 22. When the drive motor 21 drives the transmission belt 22 to move axially, the contour body 31 moves axially along the guide rail base 231 through the slider 232 with the driving force transmitted by the pressure plate 41. The conductive slider 33 and the sliding contact conductive slide rail 14 are combined to transmit the excitation and reception signals of the array eddy current coil 32, and transmit the excitation and reception commands of the array eddy current detector 5 to the array eddy current coil 32 on the contour body 31.

[0105] The drive motor 21 records and transmits the scanning position and distance of the contour body 31 in real time, and generates C-scan images through the array eddy current detector 5 to achieve uniform and stable scanning of the turbine disk blade root groove.

[0106] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0107] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A scanning mechanism for an eddy current probe array of blade root grooves in a gas turbine disk, characterized in that, It includes a probe frame, a drive module, a detection module, and a clamping device; The probe frame includes a frame body, a drive module mounting interface, an array eddy current coil communication interface, and a sliding contact conductive slide rail. The frame body has a hollow structure. The drive module mounting interfaces are located at both ends of the frame body along the axial direction, and both ends are machined with drive motor mounting holes and linear guide rail mounting holes. The array eddy current coil communication interface is located on the end face of the frame body and is used to connect to the array eddy current detector. The sliding contact conductive slide rail is installed axially in the frame body, with one end covered by insulating material and the other end connected to the array eddy current coil communication interface. The drive module includes a drive motor, a transmission belt, and a linear guide rail. There are two drive motors, which are respectively installed at both ends of the axial direction of the frame body. The transmission belt is sleeved on the two drive motor transmission pulleys, and the drive motor drives the transmission belt to move along the axial direction by rotating. There are two sets of linear guide rails, in which the linear guide rail bases are installed in the frame body through the linear guide rail mounting holes, located directly above and directly below the transmission belt, respectively. The detection module includes a profiling body, an array of eddy current coils, and a conductive slider. The profiling body's detection surface is completely fitted with the inner surface of the skeleton body, and the axial width of the profiling body is greater than the width of the array of eddy current coils. The array of eddy current coils is arranged on the profiling body's detection surface. The conductive slider is installed on the upper surface of the profiling body, connected to the array of eddy current coils via a cable, and meshes with a sliding contact conductive rail to transmit the array of eddy current coil signals. The clamping device is used to press against the drive belt, thereby controlling the movement of the detection module; The clamping device includes a pressure plate, multiple guide posts, multiple springs, an electromagnet, and a pressure head. There are two pressure plates: the lower pressure plate is connected to the contoured body and has multiple guide holes machined on it; the upper pressure plate has the same number and size of guide holes machined at corresponding positions. Multiple guide posts pass through the corresponding guide holes on the upper and lower pressure plates, and multiple springs are fitted between the upper and lower pressure plates. The upper and lower surfaces of the multiple springs contact the lower surface of the upper pressure plate and the upper surface of the lower pressure plate, respectively. The electromagnet is integrated into the upper pressure plate and located at the geometric center of the multiple guide holes on the upper pressure plate. The pressure head is located on the lower surface of the upper pressure plate and the upper surface of the lower pressure plate, respectively. The pressure head controls the pressing state with the transmission belt by switching the electromagnet on and off, thereby controlling the movement of the detection module.

2. The eddy current probe scanning mechanism for the root groove array of a gas turbine disk blade according to claim 1, characterized in that, The thickness of the contact area between the skeleton body and the profilograph detection surface is no more than 2mm, and it is made of high-strength engineering plastic.

3. The eddy current probe scanning mechanism for the root groove array of a gas turbine disk blade according to claim 1, characterized in that, The axial distance between the center of the drive motor mounting hole and the end face of the turbine disk blade root groove is greater than the sum of the axial width of the contour body and the radius of the drive motor transmission wheel.

4. The eddy current probe scanning mechanism for the root groove array of a gas turbine disk blade according to claim 1, characterized in that, The contact surface between the sliding contact conductive slide rail and the conductive slider is covered with a layer of wear-resistant, low-resistance, and low-resistance material; the interface between the sliding contact conductive slide rail and the conductive slider is shielded.

5. The eddy current probe scanning mechanism for the root groove array of a gas turbine disk blade according to claim 1, characterized in that, The drive motor is a micro stepper motor with forward and reverse rotation functions, and the motor shaft is perpendicular to the axial center plane of the turbine disk blade root groove; The diameter of the drive motor transmission wheel is not less than twice the sum of the thickness of the lower pressure plate and the pressure head.

6. The eddy current probe scanning mechanism for the root groove array of a gas turbine disk blade according to claim 1, characterized in that, The transmission belt is a flat belt with wear-resistant and anti-slip material layers on both the upper and lower surfaces. The thickness of the transmission belt is at least less than the gap between the upper pressure plate head and the lower pressure plate head when they are not pressed together.

7. The eddy current probe scanning mechanism for the root groove array of a gas turbine disk blade according to claim 1, characterized in that, The length of the arc surface of the contour detection surface is not less than the length of the arc surface of the turbine disk blade root groove cross section, and the array of eddy current coils arranged on it is the same length as the arc surface of the detection surface.

8. The eddy current probe scanning mechanism for the root groove array of a gas turbine disk blade according to claim 1, characterized in that, The arrayed eddy current coils are arranged in two staggered rows, and the time-division multiple excitation transmission and reception method is used for excitation and reception. The array of eddy current coils is arranged near the surface of the profiling detection surface to prevent damage caused by friction on the inner surface of the skeleton body during the detection process.

9. A method for scanning the root groove array of a gas turbine disk blade using an eddy current probe, characterized in that, This method is based on a gas turbine disk blade root groove array eddy current probe scanning mechanism according to any one of claims 1 to 8, comprising: The skeleton body is stably placed in the root groove of the turbine disk blade under test, so that the distances from the two end faces of the skeleton body to the end faces of the root groove of the turbine disk blade under test are equal, ensuring that the array eddy current coil can completely scan the root groove of the turbine disk blade under test axially. When the electromagnet is energized, the pressure plate is pressed onto the transmission belt. When the drive motor drives the transmission belt to move axially, the contoured body moves axially along the linear guide base through the conductive slider by the driving force transmitted by the pressure plate. The conductive slider and the sliding contact conductive rail combine to transmit the excitation and reception signals of the array eddy current coil, and transmit the excitation and reception commands of the array eddy current detector to the array eddy current coil on the contoured body. The drive motor records and transmits the scanning position and distance of the contoured object in real time, and the array eddy current detector generates a C-scan image to achieve uniform and stable scanning of the turbine disk blade root groove.

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