An array eddy current method and apparatus for detecting edge cracks in non-planar multi-dimensioned process holes

Abstract

The present application relates to a kind of array eddy current detection methods for detecting non-planar structural member with porous and different aperture, using stamp type detection device to carry out rapid detection on dense hole area, and the detection device includes flexible probe base, and a plurality of detection probes and a plurality of strain gauge sensors are respectively arranged on the lower end surface and the upper end surface of flexible probe base, and the detection probe includes flexible coil holder and array orthogonal eddy current detection coil;The alignment accuracy of detection probe is monitored using strain gauge sensor, and the detection probe can be slightly moved and deformed to adapt to the area to be detected by flexible probe base and flexible coil holder, and when the detection probe is correspondingly inserted in the hole position of the area to be detected, the array orthogonal eddy current detection coil winding detects the radioactive fatigue crack of 360° around the hole edge without rotating the probe.The present application improves the detection efficiency, avoids the situation of missed detection or repeated detection.The structure is simple and easy to operate, and has high practicability and high reliability of detection result.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of eddy current testing, in particular to an array eddy current testing method and device for non-planar multi-size process hole edge cracks. BACKGROUND

[0002] In modern industrial equipment, there are a large number of process holes such as bolts, and usually for safety reasons, these equipment need to be inspected after a period of operation to ensure safety in service. For example, there are many oil and gas holes with the same or different diameters in the piston structure of diesel locomotives. The traditional inspection process for the hole position in the piston is to use the penetration method, but the penetration method pollutes the environment, and currently this method is strictly limited. In recent years, in the field of aviation industry, whether online or in-service detection, a large number of eddy current methods are used to replace the penetration method, especially for parts with coating layers. According to the conventional eddy current method, a manual or electric rotating method is usually used to scan and detect these process holes. When the hole diameter changes, the operator needs to replace different rotating probes and re-set the instrument parameters, and using a conventional single detection probe, due to the large number of and complex hole positions, repeated detection may affect the detection efficiency or there may be missed detection. Therefore, the present application improves the prior art to solve the above problems. SUMMARY

[0003] To solve the above problems, the present application provides an array eddy current testing method for non-planar multi-size process hole edge cracks, which is implemented as follows:

[0004] An array eddy current testing method for non-planar multi-size process hole edge cracks is used to detect a non-planar structure with multiple holes and different hole diameters, and a detection device with a flexible probe holder and a plurality of detection probes is directly imprinted on the detection area. The upper end face of the flexible probe holder is attached with a film type strain gauge sensor, and a plurality of strain gauge sensors are arranged in a surface array. The detection probe includes a flexible coil holder and an array orthogonal eddy current detection coil wound on the flexible coil holder. The flexible coil holder is a cylindrical structure, and a plurality of orthogonal eddy current detection coils are arranged in a 360° annular array along the circumference of the cylindrical structure. The strain gauge sensor is used to monitor the alignment accuracy of the detection probe, and the flexible probe holder and the flexible coil holder are used to make the detection probe micro-adjustable and deformed to adapt to the detection area. When the detection probe is inserted into the hole position of the detection area, the array orthogonal eddy current detection coil is used for non-directional eddy current detection. Under the condition that the probe does not rotate, the 360° radial fatigue cracks of the hole edge are detected.

[0005] As a further improvement, the non-planar structure is an oil hole area or a gas hole area in a piston structure of an internal combustion engine, and the detection probe is arranged in an array corresponding to different hole diameters, sizes and arrangements of the detection object.

[0006] As a further improvement, the specific steps include:

[0007] S1. Detection device design and placement: a "seal type" detection device is used to number each diaphragm strain gauge sensor and correspond to the detection probe, and the detection device with several non-directional detection probes is directly placed on the detection area;

[0008] S2. Alignment adjustment: the detection probe is inserted into the hole position of the detection area, and when the alignment error is small, the flexible probe seat and the flexible coil holder can adjust the detection probe in a small error range to adapt to the hole position;

[0009] When the alignment error is large, the flexible probe seat deforms abnormally, the strain gauge sensor deforms and abnormally alarms, providing an alignment error signal, and the flexible probe seat is adjusted according to the alarm signal;

[0010] S3. Lift verification: the detection probe after the insertion hole is verified, and the lift excitation signal is used to quickly verify the accuracy of each detection probe insertion hole alignment, and when it is determined to meet the detection standard, the hole edge crack detection is performed;

[0011] S4. Hole edge crack detection: using an array of orthogonal eddy current detection coils for non-directional eddy current detection,

[0012] Without rotating the probe, the radioactive fatigue cracks on the hole edge are detected.

[0013] As a further improvement, in step S2, the adjustment of the flexible probe seat is targeted according to the signal feedback of the numbered diaphragm strain gauge sensor.

[0014] As a further improvement, in step S2, the alignment error signal provided by the diaphragm strain gauge sensor includes displacement, processing surface or inner hole shape surface, hole diameter, and hole direction.

[0015] The application also discloses an array eddy current detection device for non-planar multi-size process hole edge cracks, which is used for simultaneously detecting multiple oil hole and gas hole edge cracks in the same detection area of a piston structure of an internal combustion engine, and the diameters of the multiple oil holes and gas holes are different.

[0016] Flexible probe seat;

[0017] A plurality of detection probes, the detection probe includes a flexible coil holder and an array orthogonal eddy current detection coil, the flexible coil holder is a cylindrical structure, a plurality of orthogonal eddy current detection coils are arranged along the circumferential 360° annular array of the cylindrical structure;The detection probe is arranged on the lower end surface of the flexible probe holder, the number of the detection probe, the size of the probe and the arrangement of the probe are consistent with the arrangement of the hole position in the detection area;

[0018] A plurality of strain gauge sensors, the strain gauge sensor is a membrane type and is arranged in a surface array on the upper end surface of the flexible probe holder.

[0019] As a further improvement, a handle is further arranged on the upper end surface of the flexible probe holder, and the detection device can be detected by manually holding the handle or through the automatic clamp holding the handle.

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

[0021] Firstly, the array eddy current detection method is arranged, which can improve the detection efficiency of the crack of the hole edge of the structure with multiple holes and different hole diameters, and reduce the missed detection or repeated detection rate. The detection efficiency is reflected in three aspects. Firstly, the operator does not need to frequently replace different detection probes and reset the detection instrument parameters, which saves preparation time. Secondly, multiple hole positions can be detected at the same time, and the detection can be completed by one-time stamping without individual detection. Thirdly, the probe does not need to be rotated, and the probe is placed in the hole position to be detected, and the 360° array orthogonal eddy current detection coil arranged in the circumferential direction of the flexible coil holder is used to realize the non-directional eddy current detection, so that the radioactive fatigue crack of the hole edge can be detected without rotating the probe.

[0022] Secondly, the flexible probe holder and the flexible coil holder are designed, and when the structure and the to-be-detected area have a small error, the probe can be flexibly adjusted to adapt to the displacement error or the machining surface error of the to-be-detected structure or the hole position machining error, which has good practical performance.

[0023] Thirdly, the membrane type strain gauge sensor is arranged on the upper end surface of the flexible probe holder and deforms integrally with the flexible probe holder, so that the deformation of the flexible probe holder can be monitored. The alignment information of the detection device can be provided by monitoring the deformation, and the misalignment alarm can be given when the alignment is abnormal, so that the self-detection function of the detection device is realized. BRIEF DESCRIPTION OF DRAWINGS

[0024] 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.

[0025] Figure 1 This is a schematic diagram of the non-planar structural component (internal combustion engine piston) in this embodiment.

[0026] Figure 2 for Figure 1 A schematic diagram viewed from above.

[0027] Figure 3 The detection device in this embodiment is a simplified schematic diagram.

[0028] Figure 4 This is a schematic diagram of the detection device in the flexible deformation state of this embodiment.

[0029] Figure 5 This is a usage diagram of one application state in this embodiment.

[0030] Figure 6 This is a flowchart of the detection method of the present invention.

[0031] In the picture:

[0032] 10 - Non-planar structural component; 11 - Area to be inspected;

[0033] 20-Detection device, 21-Flexible probe holder, 22-Detection probe, 23-Strain gauge sensor, 24-Handle. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0035] In the description of this invention, 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 with "first" and "second" may explicitly or implicitly include one or more of that feature.

[0036] In modern equipment, there are a large number of process holes such as bolts, in order to ensure the safety of equipment operation, it is necessary to regularly detect these hole positions, some equipment has complex structure characteristics, and the detection difficulty and workload are large, for example, the non-planar structure with multiple holes and different hole diameters, the conventional detection method is to use a single probe for rotary detection, in the condition of dense hole position, the detection workload is large and the detection efficiency is low.

[0037] The application discloses a kind of non-planar multi-size process hole edge crack array eddy current detection methods, for detecting the non-planar structure 10 with multiple holes and different hole diameters, especially for detecting oil hole area or air hole area in internal combustion engine piston structure, the present application is directly imprinted in the area to be detected 11 using a detection device 20 with flexible probe base 21 and several detection probes 22, wherein the upper end surface of the flexible probe base 21 is attached with a diaphragm strain gauge sensor 23, and the diaphragm strain gauge sensors 23 are arranged in an array, the detection probe 22 includes a flexible coil holder and an array of orthogonal eddy current detection coils wound on the flexible coil holder, the flexible coil holder is cylindrical in structure, and the orthogonal eddy current detection coils are arranged in a 360° circular array around the cylindrical structure, the diaphragm strain gauge sensor 23 is used to monitor the alignment accuracy of the detection probe 22, and the detection probe is deformed by the flexible probe base 21 and the flexible coil holder to adapt to the area to be detected 11, when the detection probe 22 is inserted into the hole position of the area to be detected 11, the array of orthogonal eddy current detection coils is used for non-directional eddy current detection, and the radial fatigue cracks of the hole edge are detected without rotating the probe.

[0038] As a further improvement, the detection probe 22 is arranged in an array corresponding to the different hole diameters, sizes and arrangements of the detection object, and the detection object generally refers to a standard part.

[0039] As a further improvement, the specific detection steps include:

[0040] S1. Detection device design and placement: adopt "stamp type" detection device, the detection device 20 includes flexible probe base 21, the lower end surface of the flexible probe base 21 is arranged in an array with detection probes 22, the upper end surface of the flexible probe base 21 is arranged in an array with diaphragm strain gauge sensors 23, each diaphragm strain gauge sensor 23 is numbered and corresponds to the corresponding detection probe 22 above and below, and the detection device 20 with several non-directional detection probes is directly placed on the area to be detected 11;

[0041] S2. Position adjustment: the detection probe 22 is correspondingly inserted in the hole position of the to-be-detected area 22, when the position error is small, the flexible probe seat 21 and the flexible coil holder enable the detection probe to be adjusted and adapted to the hole position within a small error range;

[0042] When the position error is large, the flexible probe seat 21 is abnormally deformed, the strain gauge sensor 23 is deformed along and performs abnormal alarm, a position error signal is provided, and the flexible probe seat is adjusted according to the alarm signal;

[0043] S3. Lift-off verification: the detection probe 22 after the insertion hole is subjected to lift-off verification, a lift-off excitation signal is used to quickly verify the accuracy of the insertion hole position of each detection probe 22, and when it is determined that the detection standard is met, the hole edge crack detection is performed;

[0044] S4. Hole edge crack detection: the array orthogonal eddy current detection coil is used for non-directional eddy current detection, and the radioactive fatigue crack of 360 degrees of the hole edge is detected without rotating the probe.

[0045] The combination of the non-directional eddy current detection coil winding and the flexible probe seat 21 realizes the detection of the hole edge crack without rotation. The flexible probe seat 21 and the flexible coil are used to effectively take into account the small precision error during the process hole machining. Further, in order to overcome the position problem, the position adjustment step is designed, the diaphragm type strain gauge sensor 23 that can be integrated with the flexible probe seat 21 and follow the movement is arranged to identify whether the detection probe 22 successfully completes the position adjustment, the detection probe 22 insertion condition is judged through the monitoring of the signal of the strain gauge sensor 23, and the adjustment of the detection probe insertion is performed according to the feedback signal. The whole structure of the present application is simple, the operation is convenient, and the detection efficiency is greatly improved. Through the setting of the position adjustment and lift-off verification steps, the reliability of the detection result is improved.

[0046] As a further improvement, in the step S2, the adjustment of the flexible probe seat 21 is carried out according to the signal feedback of the numbered diaphragm type strain gauge sensor 23. Each diaphragm type strain gauge sensor 23 corresponds to a detection area, and the detection area generally corresponds to one or more detection probes 22. Through the block type monitoring, the detection area with a large error can be quickly found, and the detection probe 22 or the to-be-detected area with detection abnormalities can be conveniently adjusted and detected.

[0047] As a further improvement, in the step S2, the position error signal provided by the diaphragm type strain gauge sensor 23 includes displacement, processing surface or inner hole shape surface, hole diameter, hole direction, etc.

[0048] The application further discloses a non-planar multi-size process hole edge crack array eddy current detection device for simultaneously detecting multiple oil hole and air hole edge cracks in the same detection area of an internal combustion engine piston structure, wherein the multiple oil holes and air holes have different hole diameters.

[0049] A flexible probe base 21;

[0050] A plurality of detection probes 22, which comprise flexible coil racks and array orthogonal eddy current detection coils, the flexible coil racks are cylindrical structures, and the plurality of orthogonal eddy current detection coils are arranged in a 360° annular array along the circumferential direction of the cylindrical structure; the detection probes 22 are arranged on the lower end surface of the flexible probe base 21, the number, size and arrangement of the detection probes 22 are consistent with the arrangement of the hole positions in the detection area.

[0051] A plurality of strain gauge sensors 23, which are film type and are arranged in a surface array on the upper end surface of the flexible probe base 21, and the strain gauge sensors 23 are provided with corresponding numbers.

[0052] As a further improvement, a handle 24 is further arranged on the upper end surface of the flexible probe base 21, and the shape, material, size and the like of the handle 24 can be designed according to the detection needs; the detection device can be manually held by the handle 24 for detection or clamped by an automatic clamp for detection.

[0053] The application has the effects of improving the detection efficiency, reducing the missed detection or repeated detection rate for the hole edge cracks of the structural member with multiple holes and different hole diameters. The structure is simple and easy to operate, has good practical performance, and has the self-detection function.

[0054] The above only describes the preferred embodiments of the application and is not used to limit the application. For those skilled in the art, the application can have various modifications and changes. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A method of eddy current testing of an array of non-planar multi-dimensioned process hole edge cracks for the detection of non-planar structures having multiple holes of varying hole diameters, characterised in that, The application discloses a detection device with a flexible probe base and a plurality of detection probes for directly stamping on a detection area, wherein the upper end surface of the flexible probe base is attached with a plurality of membrane type strain gauge sensors arranged in a surface array, the detection probe comprises a flexible coil holder and an array of orthogonal eddy current detection coils wound on the flexible coil holder, the flexible coil holder is in a cylindrical structure, and the plurality of orthogonal eddy current detection coils are arranged in a 360° annular array along the circumference of the cylindrical structure; the strain gauge sensors are used for monitoring the alignment accuracy of the detection probe, and the flexible probe base and the flexible coil holder are used for enabling the detection probe to be slightly moved and deformed to adapt to the detection area; after the detection probe is inserted into the hole position of the detection area, the array of orthogonal eddy current detection coils is used for performing non-directional eddy current detection, and the radioactive fatigue cracks of 360° of the hole edge are detected without rotating the probe. The non-planar structure is an oil hole area or a gas hole area in a piston structure of an internal combustion engine, and the detection probe is correspondingly arranged in an array according to different hole diameters, sizes and arrangements of the detection objects.

2. A method of eddy current testing of an array of non-planar multi-dimensioned process hole edge cracks as claimed in claim 1, wherein, The specific steps include: S1. Detection device design and placement: a "stamp type" detection device is adopted, each membrane type strain gauge sensor is numbered, and the corresponding detection probe is arranged, and the detection device with a plurality of non-directional detection probes is directly placed on the detection area; S2. Alignment adjustment: the detection probe is inserted into the hole position of the detection area, when the alignment error is small, the flexible probe base and the flexible coil holder enable the detection probe to be slightly moved and adjusted to adapt to the hole position; when the alignment error is large, the flexible probe base is abnormally deformed, the strain gauge sensor is deformed and abnormally alarms, an alignment error signal is provided, and the flexible probe base is adjusted according to the alarm signal; S3. Lift-off verification: the detection probe after the hole insertion is verified, a lift-off excitation signal is used to quickly verify the accuracy of the hole insertion alignment of each detection probe, and the hole edge crack detection is performed when it is determined that the detection standard is met; S4. Hole edge crack detection: the array of orthogonal eddy current detection coils is used for non-directional eddy current detection, and the radioactive fatigue cracks of 360° of the hole edge are detected without rotating the probe.

3. A method of eddy current testing of an array of non-planar multi-dimensioned process hole edge cracks according to claim 2, wherein, In the step S2, the flexible probe base is adjusted according to the signal feedback of the membrane type strain gauge sensor provided with a number.

4. A method of eddy current testing of an array of edge cracks of non-planar multi-dimensioned process holes according to claim 2, wherein, In the step S2, the alignment error signal provided by the membrane type strain gauge sensor includes displacement, processing surface or inner hole surface, hole size, and hole direction.

5. An eddy current testing device for detecting an array of edge cracks of non-planar multi-dimension process holes simultaneously for detecting a plurality of oil or gas hole edge cracks in the same detection area of a piston structure of an internal combustion engine, wherein the plurality of oil or gas holes have different hole diameters, and the device is characterized in that the device is configured to detect the plurality of oil or gas hole edge cracks by using any one of the methods of claims 1 to 4. It comprises: a flexible probe base; a plurality of detection probes, the detection probe comprises a flexible coil holder and an array of orthogonal eddy current detection coils, the flexible coil holder is in a cylindrical structure, and a plurality of orthogonal eddy current detection coils are arranged in a 360° annular array along the circumference of the cylindrical structure; the detection probe is arranged on the lower end surface of the flexible probe base, the number, size and arrangement of the detection probe are consistent with the arrangement of the hole position in the detection area; a plurality of strain gauge sensors, the strain gauge sensors are membrane type and are arranged in a surface array on the upper end surface of the flexible probe base.

6. An eddy current apparatus for detecting an array of edge cracks of non-planar multi-dimensioned process holes according to claim 5, wherein, The upper end surface of the flexible probe base is also provided with a handle, and the detection device is detected by manually holding the handle or through an automatic clamp clamping the handle.

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