Multi-channel eddy current detection probe and detection method of multi-channel eddy current detection probe

Abstract

The invention discloses a multi-channel eddy current detection probe and a detection method of the multi-channel eddy current detection probe. The multi-channel eddy current detection probe comprises a probe shell, an excitation / receiving module, a switch circuit board, an I / O signal line and a sealing cover. Arc surfaces are arranged on the two sides of the bottom of a probe shell, the radius of the arc surfaces is equal to the radius of the arc surface of an arc area of a bearing component to be detected, a plurality of coil mounting holes are formed in the surface of the bottom of the probe shell at intervals, an excitation / receiving module is arranged in the coil mounting holes, and a switch circuit board is connected with the excitation / receiving module. The non-destructive testing device is used for realizing non-destructive testing of arc-shaped areas at corners of T-shaped and L-shaped bearing members, solves the technical problem that the arc-shaped areas at the corners of the bearing members cannot be subjected to non-destructive testing, and improves the detection efficiency.

Description

Technical Field

[0001] The invention relates to the field of nondestructive testing of load-bearing components, and in particular to a multi-channel eddy current testing probe and a multi-channel eddy current testing probe testing method. Background Art

[0002] In industrial design, the corners of T-shaped and L-shaped load-bearing components are transitioned with arc-shaped areas. This area will produce stress concentration during use, so fatigue crack defects are prone to occur. In order to prevent the failure of load-bearing components during use, non-destructive testing of this area is required regularly. However, due to the small size of the arc-shaped area during service and the installation of parts such as hanging bolts around it, there are many difficulties in implementing non-destructive testing methods in this area.

[0003] In order to achieve convenient and effective detection of fatigue cracks in the arc-shaped area of ​​load-bearing components and ensure stable operation of mechanical equipment, the present invention provides a multi-channel eddy current detection probe and a multi-channel eddy current detection probe detection method for performing rapid, reliable and high-precision detection of the arc-shaped area of ​​load-bearing components. Summary of the invention

[0004] The purpose of the present invention is to provide a multi-channel eddy current detection probe and a multi-channel eddy current detection probe detection method, which are used to realize non-destructive detection of arc-shaped areas at the corners of T-shaped and L-shaped load-bearing components, and solve the technical problem that non-destructive detection cannot be implemented in the arc-shaped areas at the corners of load-bearing components.

[0005] To achieve the above object, the technical solution of the present invention is:

[0006] The present invention discloses a multi-channel eddy current detection probe, comprising a probe housing, an excitation / receiving module, a switch circuit board, an I / O signal line and a sealing cover; the two sides of the bottom of the probe housing are arranged as arc surfaces, the radius of the arc surface is equal to the radius of the arc surface of the arc-shaped area of ​​the load-bearing component to be detected, the top of the probe housing is arranged with an opening, and the interior of the probe housing is arranged with a cavity; a plurality of coil mounting holes are arranged at intervals on the bottom surface of the probe housing, the excitation / receiving module is arranged in the coil mounting holes, the switch circuit board is arranged in the cavity, and the switch circuit board is connected to the excitation / receiving module; the I / O signal line passes through the sealing cover to connect the switch circuit board with external equipment for signal communication and power supply; the sealing cover and the probe housing fix and seal the opening.

[0007] Furthermore, a bottom plane area, a curved surface area, and a side plane area are provided at the bottom of the probe housing, and the coil mounting holes are arranged perpendicular to the bottom surface of the probe housing, and the coil mounting holes are arranged obliquely in the bottom plane area, the curved surface area, and the side plane area.

[0008] Furthermore, the center distance between two adjacent coil mounting holes is smaller than the diameter of the coil mounting holes.

[0009] Furthermore, the transverse distance between two adjacent coil mounting holes is the same as the transverse distance between two adjacent coil mounting holes, and the transverse distance between two adjacent coil mounting holes is smaller than the diameter of the coil mounting holes.

[0010] Furthermore, the excitation / receiving module includes a coil group and a magnetic field collecting structure, the coil group includes a plurality of hollow coils, the magnetic field collecting structure includes a plurality of cylindrical magnetic cores, the hollow coils are arranged in the coil mounting holes and are coaxial with the coil mounting holes, and a hollow coil is placed in each of the coil mounting holes; the magnetic core is placed in the inner cavity of the hollow coil and is coaxial with the hollow coil.

[0011] Furthermore, a four-to-one multiplexing circuit is provided on the switch circuit board, and the multiplexing circuit includes a first switch chip, a second switch chip and a plurality of balancing resistors; the common input terminals of the first switch chip and the second switch chip are interconnected, and the common output terminals of the first switch chip and the second switch chip are interconnected; the independent input terminal and the independent output terminal of the first switch chip are respectively connected to a balancing resistor, and the independent input terminal and the independent output terminal of the second switch chip are respectively connected to an air-core coil in the coil group, a balancing resistor and an air-core coil are connected in series through the first switch chip and the second switch chip to form a sub-link, and the two sub-links form a bridge structure; a pulse signal is input into the first switch chip and the second switch chip to control the on and off of each of the bridge structures.

[0012] Furthermore, the coil group includes eight hollow coils, the magnetic field focusing structure includes eight cylindrical magnetic cores, the first switch chip and the second switch chip include two-way selection switches of four channels, the pulse signal is generated by a detection device, and the pulse signal is a high-level signal or a low-level signal to control the four channels of the first switch chip and the second switch chip to be turned on in sequence. When one of the channels is turned on, the other three channels are disconnected. The pulse signal controls the two-way selection switches of each channel of the first switch chip and the second switch chip to be opened or closed synchronously.

[0013] Furthermore, the four groups of independent input terminals of the first switch chip jointly receive the excitation signal of the eddy current detection equipment, the first switch chip selects the corresponding channel, and the excitation signal enters the common input terminal of the second switch chip; the second switch chip selects the corresponding channel, and the excitation signal enters the corresponding coil group for excitation, and the coil group receives the excitation signal to generate an alternating magnetic field, and the alternating magnetic field generates an eddy current signal in the arc-shaped area of ​​the workpiece to be detected. At the same time, the coil group feeds back the eddy current detection signal of the arc-shaped area of ​​the workpiece to be detected through electromagnetic induction; the eddy current detection signal enters the common output terminal of the second switch chip, and enters the detection equipment through the common output terminal.

[0014] Furthermore, the excitation signal, the eddy current detection signal, and the pulse signal are transmitted through the I / O signal line.

[0015] Furthermore, the multi-channel eddy current detection probe also includes a fixing screw; the excitation / receiving module is fixed in the cavity of the probe housing; the sealing cover is sealed and connected to the open edge of the top of the probe housing through the fixing screw.

[0016] The present application also provides a multi-channel eddy current detection probe detection method as described above, comprising the steps of:

[0017] Connecting the multi-channel eddy current testing probe to the multi-channel eddy current testing equipment;

[0018] Placing the multi-channel eddy current detection probe on the surface of the arc-shaped area of ​​the load-bearing component to be inspected, wherein the arc surface of the multi-channel eddy current detection probe is arranged corresponding to the arc surface of the arc-shaped area of ​​the load-bearing component to be inspected;

[0019] Press the probe housing of the multi-channel eddy current detection probe to fully couple the bottom surface where the excitation / receiving module of the multi-channel eddy current detection probe is located with the surface of the arc-shaped area of ​​the load-bearing component to be detected;

[0020] The multi-channel eddy current detection probe is pushed at a uniform speed along the extension direction of the arc-shaped area of ​​the load-bearing component to be detected until all the arc-shaped areas of the load-bearing component to be detected are detected.

[0021] By adopting the above technical solution, the present invention has the following beneficial effects:

[0022] The present application provides a multi-channel eddy current detection probe and a multi-channel eddy current detection probe detection method, wherein both sides of the bottom of the probe housing are arranged as arc surfaces, the radius of the arc surface is equal to the radius of the arc surface of the arc-shaped area of ​​the load-bearing component to be detected, a plurality of coil mounting holes are arranged at intervals on the bottom surface of the probe housing, an excitation / receiving module is arranged in the coil mounting holes, a switch circuit board is connected to the excitation / receiving module, and is used to realize non-destructive detection of the arc-shaped area at the corner of T-shaped and L-shaped load-bearing components, thereby solving the technical problem that non-destructive detection cannot be implemented in the arc-shaped area at the corner of the load-bearing component, and improving the detection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the disassembled structure of the multi-channel eddy current detection probe of the present invention;

[0024] Figure 2 It is a structural schematic diagram of the probe housing of the present invention;

[0025] Figure 3 is a side view of the probe housing of the present invention;

[0026] Figure 4 A multiplexing circuit diagram in a switch circuit board of the present invention;

[0027] Figure 5 It is an equivalent four-channel bridge structure circuit diagram of the multiplexing circuit diagram of the present invention;

[0028] Figure 6 It is a schematic diagram of the detection when the multi-channel eddy current detection probe of the present invention is applied to the arc-shaped area of ​​a load-bearing component;

[0029] Figure 7 The multi-channel eddy current detection probe of the present invention is applied to detect defect signals of arc-shaped areas of load-bearing components.

[0030] The accompanying drawings are marked as:

[0031] 1 probe housing, 2 coil group, 3 magnetic focusing structure, 4 switch circuit board, 5 I / O signal line, 6 sealing cover, 7 fixing screws, 8 load-bearing component to be inspected, 9 hanging bolts, 10 defect detection signal, 101 mounting cover screw hole, 102 sealing cover fixing screw hole, 401 first switch chip, 402 second switch chip, 403 balancing resistor, 404 bridge coil equivalent resistor, 801 arc area, 802 fatigue crack. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] like Figure 1 As shown, the present invention discloses a multi-channel eddy current detection probe suitable for fatigue crack defect detection in arc-shaped areas of load-bearing components, comprising a probe housing 1, a coil group 2, a magnetic field collecting structure 3, a switch circuit board 4, an I / O signal line 5 and a sealing cover 6. The coil group 2 and the magnetic field collecting structure 3 form an excitation / receiving module.

[0034] like Figure 2 , Figure 3 As shown, both sides of the bottom of the probe housing 1 are arranged as arc surfaces, and the radius R of the arc surface is equal to the radius R' of the arc surface of the arc-shaped area of ​​the load-bearing component to be detected; the top of the probe housing 1 is arranged with an opening, and the interior of the probe housing 1 is arranged with a cavity; a plurality of coil mounting holes 101 are arranged at intervals on the bottom surface of the probe housing 1, the excitation / receiving module is arranged in the coil mounting holes 101, the switch circuit board 4 is arranged in the cavity, and the switch circuit board 4 is connected to the excitation / receiving module; the I / O signal line passes through the sealing cover 6 to connect the switch circuit board 4 with the signal communication of the external device and to supply power; the sealing cover 6 and the probe housing 1 fix and seal the opening.

[0035] A bottom plane area, a curved surface area, and a side plane area are provided at the bottom of the probe housing 1. The coil mounting hole 101 is arranged perpendicular to the bottom surface of the probe housing. The coil mounting hole 101 is arranged obliquely in the bottom plane area, the curved surface area, and the side plane area.

[0036] The center distance between two adjacent coil mounting holes 101 is smaller than the diameter of the coil mounting holes 101. The lateral distance between two adjacent coil mounting holes 101 is the same as the lateral distance between two adjacent coil mounting holes 101, and the lateral distance between two adjacent coil mounting holes 101 is smaller than the diameter of the coil mounting holes. Eight coil mounting holes 101 are arranged at equal intervals in the bottom plane area, the curved surface area, and the side plane area of ​​the probe housing 1, and the diameter of the coil mounting hole 101 is d; the coil group 2 includes a total of multiple hollow coils. In order to eliminate the detection blind area between the hollow coils, the hollow coils are arranged in an inclined manner, and the lateral distance X1 between two adjacent coil mounting holes 101 is d-0.5mm, and the longitudinal distance Y1 between two adjacent coil mounting holes 101 is d-0.5mm. This distribution method can make the area scanned by adjacent hollow coils have a scanning overlap area of ​​0.5mm.

[0037] The excitation / receiving module includes a coil group 2 and a magnetic field collecting structure 3, the coil group 2 includes a plurality of hollow coils, the magnetic field collecting structure 3 includes a plurality of cylindrical magnetic cores, the hollow coils are arranged in the coil mounting hole 101 and are coaxial with the coil mounting hole 101, and a hollow coil is placed in each of the coil mounting holes 101; the magnetic core is placed in the inner cavity of the hollow coil and is coaxial with the hollow coil.

[0038] Among them, coil group 2 contains 8 hollow coils with the same parameters. The outer diameter of the hollow coil is r 外 =d, which are placed in 8 corresponding coil mounting holes 101 respectively, the outer arc surface of the hollow coil is tightly fitted with the inner wall of the coil mounting hole 101, and the bottom surface of the hollow coil is sunk into the coil mounting hole 101 by 0.5mm to prevent the hollow coil from directly contacting the surface of the workpiece to be inspected during the detection process.

[0039] The magnetic concentrator structure 3 contains 8 cylindrical magnetic cores with the same parameters. The outer diameter of the magnetic core is r 芯 Equal to the inner diameter of the hollow coil r 内 , which are placed in 8 corresponding inner holes of the hollow coils, the outer arc surface of the magnetic core fits tightly with the inner hole of the hollow coil, keeping the bottom surface of the magnetic core flush with the bottom surface of the coil; the magnetic structure material is electrical pure iron, which has ultra-high magnetic permeability, can effectively enhance the excitation magnetic field and improve detection sensitivity.

[0040] like Figure 4As shown, the multiplexing circuit in the switch circuit board 4 includes two first switch chips 401 and second switch chips 402 with the same parameters; a balancing resistor 403, numbered R0, ..., R7; the bridge coil equivalent resistance 404 of the air-core coil in the coil group 2 is coil0, ..., coil7; and the pulse signal 405 controls the on / off of each channel of the first switch chip 401 and the second switch chip 402 by inputting a high / low level.

[0041] The switch circuit board 4 is provided with a four-to-one multiplexing circuit, and the multiplexing circuit includes a first switch chip 401, a second switch chip 402 and a plurality of balancing resistors 403; the common input end of the first switch chip 401 and the second switch chip 402 are interconnected, and the common output end of the first switch chip 401 and the second switch chip 402 are interconnected; the independent input end and the independent output end of the first switch chip 401 are respectively connected to a balancing resistor, and the independent input end and the independent output end of the second switch chip 402 are respectively connected to an air-core coil in the coil group 2, a balancing resistor and an air-core coil are connected in series through the first switch chip 401 and the second switch chip 402 to form a sub-link, and the two sub-links form a bridge structure; the pulse signal 405 is input into the first switch chip 401 and the second switch chip 402 to control the on and off of each of the bridge structures.

[0042] The coil group 2 includes eight hollow coils, the magnetic focusing structure 3 includes eight cylindrical magnetic cores, the first switch chip 401 and the second switch chip 402 include two-way selection switches for four channels, and the pulse signal 405 is generated by a detection device. The pulse signal 405 is a high-level signal or a low-level signal to control the four channels of the first switch chip 401 and the second switch chip 402 to be turned on in sequence. When one of the channels is turned on, the other three channels are disconnected. The pulse signal 405 controls the two-way selection switches of each channel of the first switch chip 401 and the second switch chip 402 to be turned on or off synchronously.

[0043] The four groups of independent input ends of the first switch chip 401 jointly receive the excitation signal of the eddy current detection equipment. The first switch chip 401 selects the corresponding channel, and the excitation signal enters the common input end of the second switch chip 402; the second switch chip 402 selects the corresponding channel, and the excitation signal enters the corresponding coil group for excitation. The coil group receives the excitation signal to generate an alternating magnetic field, and the alternating magnetic field generates an eddy current signal in the arc-shaped area of ​​the workpiece to be detected. At the same time, the coil group feeds back the eddy current detection signal of the arc-shaped area of ​​the workpiece to be detected through electromagnetic induction; the eddy current detection signal enters the common output end of the second switch chip 402, and enters the detection equipment through the common output end.

[0044] like Figure 5 As shown, Figure 5 for Figure 4 The equivalent four-channel bridge structure circuit is as follows: the first switch chip 401 includes a 2-way switch of 4 channels, wherein the switch X0 and the switch Y0 control the on and off of the resistor R0 and the resistor X4, ..., the switch X3 and the switch Y3 control the on and off of the resistor R3 and the resistor R7, and the two resistors of each channel constitute the two bridge arms Z1 and Z2 of the bridge; the second switch chip 402 includes a 2-way switch of 4 channels, wherein the switch X0 and the switch Y0 control the on and off of the resistor coil0 and the resistor coil4, ..., the switch X3 and the switch Y3 control the on and off of the resistor coil3 and the resistor coil7, and the two hollow coils of each channel constitute the two bridge arms Z1 and Z2 of the bridge. bridge arms Z3 and Z4; when the high-level pulse signal reaches the first switch chip 401 and the second switch chip 402 synchronously, the switches X0 and Y0 of the two chips are closed at the same time, the bridge circuit is turned on, the excitation signal enters the bridge drive coil to generate a magnetic field, the magnetic field enters the component to be detected to generate eddy current, and the coil simultaneously picks up the feedback signal and sends it to the common output end of chip 402 to enter the eddy current detection equipment; during the detection process, when the component to be detected has no defects, the bridge satisfies Z1Z4=Z2Z3, and the output voltage ΔV=0 at this time; when the component to be detected has defects, the bridge satisfies Z1Z4≠Z2Z3, and the output voltage ΔV≠0 at this time.

[0045] Channels 1, ..., 4 are turned on in sequence through high / low level signals. When one of the channels is turned on, the other three channels are turned off, thereby reducing the noise of the entire circuit.

[0046] The excitation signal, eddy current detection signal, and pulse signal 405 of the high / low level signal are all transmitted through the I / O signal line 5, and the I / O signal line is a shielded signal line.

[0047] The multi-channel eddy current detection probe also includes a fixing screw 7; the excitation / receiving module and the switch circuit board 4 are placed in the cavity of the probe housing, and the electronic sealing glue is injected into the cavity for fixing. The opening at the top of the probe housing 1 is sealed by a sealing cover 6 and a fixing screw 7. That is, the sealing cover 6 is sealed and connected to the edge of the opening at the top of the probe housing 1 by the fixing screw 7. The four end points at the top of the probe housing 1 are provided with sealing cover fixing screw holes 102, and the fixing screws 7 are connected to the sealing cover fixing screw holes 102.

[0048] The present invention adopts four groups of bridge structures and carries eight detection coils for scanning. Adjacent coils are partially overlapped to eliminate the detection blind area, so that one scan can fully cover the arc-shaped area of ​​the load-bearing component and its surrounding area, thereby improving the detection sensitivity and scanning efficiency. The detection method provided by the present invention can perform in-service detection of the arc-shaped area of ​​the load-bearing component with coating, further improving the efficiency of non-destructive testing and realizing the greening of non-destructive testing.

[0049] This embodiment also provides a detection method using a multi-channel eddy current detection probe, comprising the following steps:

[0050] Step S1) connecting the multi-channel eddy current detection probe to the multi-channel eddy current detection device; specifically: the eddy current detection device is connected to the multi-channel eddy current detection probe via the I / O signal line 5;

[0051] Step S2) placing the multi-channel eddy current detection probe on the arc surface of the load-bearing component to be inspected, and the arc surface of the multi-channel eddy current detection probe is arranged corresponding to the arc surface of the arc area of ​​the load-bearing component to be inspected; specifically: the sensitive surface of the eddy current detection probe is closely attached to the arc surface of the load-bearing component 8 to be inspected, and at this time, the axis of the excitation coil is perpendicular to the detection surface;

[0052] Step S3) pressing the probe housing of the multi-channel eddy current detection probe so that the bottom surface where the excitation / receiving module of the multi-channel eddy current detection probe is located is fully coupled with the arc-shaped area surface of the load-bearing component to be detected; specifically: the eddy current detection device generates a sinusoidal excitation signal and a synchronous pulse signal, the excitation signal excites each coil group in a time-sharing manner through a switch circuit controlled by the synchronous pulse signal, the coil group generates a high-frequency electromagnetic field and enhances the induced magnetic field strength through a magnetic core, the induced magnetic field fully penetrates into the matrix material of the component to be detected, and at the same time the coil group picks up the eddy current detection signal containing the defect information of the detection part, and transmits the eddy current detection signal to the detection device through the switch circuit;

[0053] Step S4), push the multi-channel eddy current detection probe at a uniform speed along the extension direction of the arc-shaped area of ​​the load-bearing component to be detected until all the detection of the arc-shaped area of ​​the load-bearing component to be detected is completed; specifically: push the multi-channel probe at a uniform speed and always keep the probe sensitive surface and the arc-shaped area of ​​the load-bearing component fully coupled, and observe the display interface of the eddy current detection equipment at the same time.

[0054] like Figure 6 As shown, the load-bearing component 8 to be inspected is fixed on the hanging bolt 9, and the load-bearing component 8 to be inspected has an arc-shaped area 801. If a fatigue crack 802 defect occurs in the arc-shaped area 801, a defect signal 10 will appear in the channel window corresponding to the display interface. Figure 7As shown, the defect signal 10 is in the S2:P2 window; the display signals at the non-defective locations are shown in the other three windows S1:P1, S3:P3, and S4:P4.

[0055] The eddy current detection circuit is composed of a bridge structure and a coil group, so that the two coils of the bridge arm can work at the same time and have the same sensitivity, which improves the eddy current detection efficiency; the multiplexing circuit is adopted so that the eddy current detection equipment can drive four groups (8) of coils for detection in a time-sharing manner under the condition of only one group of excitation and reception, which further improves the detection efficiency;

[0056] Two switch circuit boards are used to construct the bridge circuit, so that when one group of bridges is working, the other three groups of bridges are in an open circuit state, which reduces the interference signal in the circuit and improves the stability and reliability of the eddy current detection signal;

[0057] The size of the detection probe is designed by profiling the R-angle structure size, so that the sensitive surface of the probe can be fully coupled with the surface to be detected during the detection process, thereby improving the detection sensitivity; the eddy current detection probe is small in size and can perform high-precision detection in a narrow arc-shaped area; the coil groups are arranged in a partially overlapping manner, eliminating the missed detection of the area between adjacent coils;

[0058] The multi-channel eddy current detection probe can perform in-service inspection on the arc-shaped area of ​​the component with a non-conductive coating, realizing the greening of non-destructive testing.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-channel eddy current detection probe, characterized in that: It includes a probe housing, an excitation / receiving module, a switch circuit board, an I / O signal line and a sealing cover; the two sides of the bottom of the probe housing are arranged as arc surfaces, the radius of the arc surface is equal to the radius of the arc surface of the arc-shaped area of ​​the load-bearing component to be detected, the top of the probe housing is arranged with an opening, and the inside of the probe housing is arranged with a cavity; a plurality of coil mounting holes are arranged at intervals on the bottom surface of the probe housing, the excitation / receiving module is arranged in the coil mounting holes, the switch circuit board is arranged in the cavity, and the switch circuit board is connected to the excitation / receiving module; the I / O signal line passes through the sealing cover to connect the switch circuit board with the external device for signal communication and power supply; the sealing cover and the probe housing fix and seal the opening.

2. The multi-channel eddy current detection probe according to claim 1, characterized in that: A bottom plane area, a curved surface area, and a side plane area are provided at the bottom of the probe housing. The coil mounting holes are arranged perpendicular to the bottom surface of the probe housing. The coil mounting holes are arranged obliquely in the bottom plane area, the curved surface area, and the side plane area.

3. The multi-channel eddy current detection probe according to claim 2, characterized in that: The center distance between two adjacent coil installation holes is smaller than the diameter of the coil installation holes.

4. The multi-channel eddy current detection probe according to claim 3, characterized in that: The transverse distance between two adjacent coil mounting holes is the same as the transverse distance between two adjacent coil mounting holes, and the transverse distance between two adjacent coil mounting holes is smaller than the diameter of the coil mounting holes.

5. The multi-channel eddy current detection probe according to claim 1, characterized in that: The excitation / receiving module includes a coil group and a magnetic field collecting structure. The coil group includes a plurality of hollow coils. The magnetic field collecting structure includes a plurality of cylindrical magnetic cores. The hollow coils are arranged in the coil mounting holes and are coaxial with the coil mounting holes. A hollow coil is placed in each of the coil mounting holes. The magnetic core is placed in the inner cavity of the hollow coil and is coaxial with the hollow coil.

6. The multi-channel eddy current detection probe according to claim 5, characterized in that: A four-to-one multiplexing circuit is provided on the switch circuit board, and the multiplexing circuit includes a first switch chip, a second switch chip and a plurality of balancing resistors; the common input terminal of the first switch chip and the second switch chip are connected to each other, and the common output terminal of the first switch chip and the second switch chip are connected to each other; the independent input terminal and the independent output terminal of the first switch chip are respectively connected to a balancing resistor, and the independent input terminal and the independent output terminal of the second switch chip are respectively connected to an air-core coil in the coil group, a balancing resistor and an air-core coil are connected in series through the first switch chip and the second switch chip to form a sub-link, and the two sub-links form a bridge structure; a pulse signal is input into the first switch chip and the second switch chip to control the on and off of each of the bridge structures.

7. The multi-channel eddy current detection probe according to claim 5, characterized in that: The coil group includes eight hollow coils, the magnetic field gathering structure includes eight cylindrical magnetic cores, the first switch chip and the second switch chip include two-way selection switches for four channels, the pulse signal is generated by a detection device, and the pulse signal is a high-level signal or a low-level signal to control the four channels of the first switch chip and the second switch chip to be turned on in sequence. When one of the channels is turned on, the other three channels are disconnected. The pulse signal controls the two-way selection switches of each channel of the first switch chip and the second switch chip to be turned on or off synchronously.

8. The multi-channel eddy current detection probe according to claim 6, characterized in that: The four groups of independent input ends of the first switch chip jointly receive the excitation signal of the eddy current detection equipment, the first switch chip selects the corresponding channel, and the excitation signal enters the common input end of the second switch chip; the second switch chip selects the corresponding channel, and the excitation signal enters the corresponding coil group for excitation, and the coil group receives the excitation signal to generate an alternating magnetic field, and the alternating magnetic field generates an eddy current signal in the arc-shaped area of ​​the workpiece to be detected. At the same time, the coil group feeds back the eddy current detection signal of the arc-shaped area of ​​the workpiece to be detected through electromagnetic induction; the eddy current detection signal enters the common output end of the second switch chip, and enters the detection equipment through the common output end.

9. The multi-channel eddy current detection probe according to claim 7, characterized in that: The excitation signal, the eddy current detection signal, and the pulse signal are transmitted via the I / O signal line.

10. The multi-channel eddy current detection probe according to claim 8, characterized in that: It also includes fixing screws; the excitation / receiving module is fixed in the cavity of the probe housing; the sealing cover is sealed and connected to the open edge of the top of the probe housing through the fixing screws.

11. A multi-channel eddy current detection probe detection method according to any one of claims 1 to 9, characterized in that: Includes steps: Connecting the multi-channel eddy current testing probe to the multi-channel eddy current testing equipment; Placing the multi-channel eddy current detection probe on the surface of the arc-shaped area of ​​the load-bearing component to be inspected, wherein the arc surface of the multi-channel eddy current detection probe is arranged corresponding to the arc surface of the arc-shaped area of ​​the load-bearing component to be inspected; Press the probe housing of the multi-channel eddy current detection probe to fully couple the bottom surface where the excitation / receiving module of the multi-channel eddy current detection probe is located with the surface of the arc-shaped area of ​​the load-bearing component to be detected; The multi-channel eddy current detection probe is pushed at a uniform speed along the extension direction of the arc-shaped area of ​​the load-bearing component to be detected until all the arc-shaped areas of the load-bearing component to be detected are detected.

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