CN117589862A - Magnetic chromatography detection device and method - Google Patents
Magnetic chromatography detection device and method Download PDFInfo
- Publication number
- CN117589862A CN117589862A CN202410075246.9A CN202410075246A CN117589862A CN 117589862 A CN117589862 A CN 117589862A CN 202410075246 A CN202410075246 A CN 202410075246A CN 117589862 A CN117589862 A CN 117589862A
- Authority
- CN
- China
- Prior art keywords
- current
- defect
- peak voltage
- ferromagnetic material
- magnetization
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 98
- 238000001514 detection method Methods 0.000 title claims abstract description 94
- 238000004587 chromatography analysis Methods 0.000 title claims abstract description 32
- 238000000034 method Methods 0.000 title claims abstract description 26
- 230000007547 defect Effects 0.000 claims abstract description 112
- 239000003302 ferromagnetic material Substances 0.000 claims abstract description 77
- 230000005415 magnetization Effects 0.000 claims abstract description 68
- 230000035699 permeability Effects 0.000 claims abstract description 52
- 239000000523 sample Substances 0.000 claims abstract description 51
- 230000006698 induction Effects 0.000 claims abstract description 38
- 230000003750 conditioning effect Effects 0.000 claims abstract description 22
- 238000009933 burial Methods 0.000 claims abstract description 12
- 230000005294 ferromagnetic effect Effects 0.000 claims description 10
- 238000006073 displacement reaction Methods 0.000 claims description 8
- 239000002344 surface layer Substances 0.000 claims description 6
- 238000012360 testing method Methods 0.000 claims description 5
- 230000005284 excitation Effects 0.000 claims description 3
- 230000000149 penetrating effect Effects 0.000 claims 1
- 229910000831 Steel Inorganic materials 0.000 description 6
- 239000010959 steel Substances 0.000 description 6
- 238000010586 diagram Methods 0.000 description 4
- 229920006395 saturated elastomer Polymers 0.000 description 3
- 238000004088 simulation Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 239000006247 magnetic powder Substances 0.000 description 2
- 238000009659 non-destructive testing Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000002925 chemical effect Effects 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 230000035882 stress Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
- G01N27/82—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws
- G01N27/83—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws by investigating stray magnetic fields
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
The invention provides a magnetic chromatography detection device and a method, wherein the device comprises a direct current magnetizer, an induction coil probe, a power supply module and a signal conditioning module, wherein the power supply module outputs a step current to change the magnetic field intensity of the direct current magnetizer, so that the step magnetization of a ferromagnetic material to be detected is realized, the induction coil probe is used for detecting the corresponding voltage of magnetic permeability disturbance generated by internal defects on the upper surface of the ferromagnetic material to be detected, the defect position is determined according to the detected peak voltage, and the defect burial depth is determined according to the peak voltage increment. The invention utilizes the characteristic of peak voltage sudden increase when the internal defect of the ferromagnetic material to be detected is magnetized, analyzes the peak voltage increment, characterizes the defect to be magnetized by the inflection point of the peak voltage increment, and determines the defect buried depth by the current value corresponding to the inflection point and a comparison table of preset current and magnetization depth, thereby realizing accurate detection of the internal defect buried depth.
Description
Technical Field
The invention relates to the technical field of nondestructive testing of ferromagnetic materials, in particular to a magnetic chromatography detection device and method.
Background
Most magnetic leakage flaw detection equipment can realize detection of flaws on the outer surface and the inner surface of a ferromagnetic element, and the detection method for the surface defects of the ferromagnetic element mainly comprises magnetic powder detection, eddy current detection, penetration detection, magnetic leakage detection and the like; the seepage detection is commonly used for the detection of porous materials and the magnetic powder detection, wherein the defects of the near surface or the surface of a structural member are detected by means of a leakage magnetic field generated by the interaction of the defects and a magnetic field, the two detection means mainly depend on the experience and visual judgment of nondestructive inspection staff, the automation level is low, the detection result is easily influenced by the attachment on the surface of a detection object, and the workload of the inspection staff is high; the eddy current detection is characterized in that the eddy current is sensitive to crack defects, but the detection effect on pits is poor;
in industry, the ferromagnetic element is subjected to internal fluid load tensile stress and physical and chemical effects, so that defects such as corrosion, cracks and the like are easy to generate, the defect size span is large, the defects are easy to expand from tens of micrometers to tens of millimeters, particularly in the depth direction, the damage is extremely large, for example, the main steam pipeline is large in pipe diameter and thick in pipe wall, the wall thickness can reach 40 millimeters, the sensor acquires disturbance information of deep defects and experiences attenuation of larger space distance compared with surface defects, detection is more difficult, and the thick-wall pipeline has higher requirements on nondestructive detection.
However, there is still no good electromagnetic nondestructive testing method for measuring the depth of the macroscopic defect inside the ferromagnetic element, so it is highly desirable to provide a device for accurately detecting the depth of the macroscopic defect inside the ferromagnetic material.
Disclosure of Invention
In view of the foregoing, it is necessary to provide a magnetic chromatography detection apparatus and method for solving the technical problem that the buried depth of the internal defect of the ferromagnetic material cannot be accurately detected.
In order to solve the problems, the invention provides a magnetic chromatography detection device, which comprises a direct current magnetizer, an induction coil probe, a power supply module and a signal conditioning module;
the direct-current magnetizer and the induction coil probe are arranged on the upper surface of the ferromagnetic material to be detected, the power supply module is respectively connected with the direct-current magnetizer, the induction coil probe and the signal conditioning module, and the signal conditioning module is connected with the induction coil probe;
the direct current magnetizer is used for carrying out step magnetization on the ferromagnetic material to be tested based on the step current output by the power supply module;
the induction coil probe is used for carrying out defect detection in the process that the ferromagnetic material to be detected is magnetized by steps to obtain a magnetic permeability disturbance detection signal corresponding to the step current;
the signal conditioning module is used for processing the magnetic permeability disturbance detection signal to obtain peak voltage and peak voltage increment corresponding to the ladder current, determining a defect position according to the peak voltage, and determining defect burial depth according to a current value of an inflection point of the peak voltage increment and a comparison table of preset current and magnetization depth.
Optionally, the induction coil probe comprises an excitation coil and a detection coil;
the exciting coil is used for exciting a magnetic field on the surface layer of the ferromagnetic material to be detected;
the detection coil is used for detecting the magnetic permeability change condition of the ferromagnetic material to be detected in the magnetization direction and generating a corresponding magnetic permeability disturbance detection signal.
Optionally, the direct current magnetizer is a magnetic yoke type magnetizer formed by a U-shaped ferromagnetic body and a pass-through coil.
Optionally, the pass-through coil is connected with the power module, and two yokes of the U-shaped ferromagnetic body are vertically arranged on the upper surface of the ferromagnetic material to be tested.
Optionally, the direct current magnetizer is a pass-through direct current coil magnetizer.
Furthermore, the invention also provides a magnetic chromatography detection method, which is applied to the magnetic chromatography detection device and comprises the following steps:
the power module outputs a step current to control the direct current magnetizer to carry out step magnetization on the ferromagnetic material to be tested;
performing defect detection by adopting an induction coil probe in the process that the ferromagnetic material to be detected is magnetized by steps to obtain a magnetic permeability disturbance detection signal corresponding to the step current;
and processing the magnetic permeability disturbance detection signal based on a signal conditioning module to obtain peak voltage and peak voltage increment corresponding to the step current, determining a defect position according to the peak voltage, and determining the defect burial depth according to the current value of the inflection point of the peak voltage increment and a comparison table of preset current and magnetization depth.
Optionally, before the step current is output through the power module to control the dc magnetizer to perform step magnetization on the ferromagnetic material to be tested, the method further includes:
and performing magnetization test on ferromagnetic materials with different defect buries to obtain the preset current and magnetization depth comparison table.
Optionally, the step magnetizing of the ferromagnetic material to be tested by the dc magnetizer controlled by the step current output by the power module includes:
outputting the step current which gradually increases to the direct current magnetizer through the power supply module;
and the direct current magnetizer carries out the step magnetization of which the magnetization intensity is increased gradually on the ferromagnetic material to be tested according to the step current.
Optionally, the detecting the defect by using an induction coil probe in the process that the ferromagnetic material to be detected is magnetized by steps to obtain a magnetic permeability disturbance detection signal corresponding to the step current includes:
scanning the upper surface of the ferromagnetic material to be tested along the axial direction of the ferromagnetic material to be tested by adopting an induction coil probe in the process of magnetizing the ferromagnetic material to be tested in a step manner to obtain a plurality of groups of voltage value sets corresponding to the step currents one by one;
and generating the magnetic permeability disturbance detection signal according to the multiple groups of voltage value sets.
Optionally, the processing the magnetic permeability disturbance detection signal based on the signal conditioning module to obtain a peak voltage and a peak voltage increment corresponding to the step current, determining a defect position according to the peak voltage, and determining a defect burial depth according to a current value of an inflection point of the peak voltage increment and a preset current and magnetization depth comparison table, including:
generating a plurality of groups of probe displacement voltage curves corresponding to the ladder currents one by one according to the magnetic permeability disturbance detection signals;
determining a plurality of groups of peak voltages according to the plurality of groups of probe displacement voltage curves and determining the defect positions according to probe positions corresponding to the peak voltages;
calculating the difference value of the peak voltages corresponding to adjacent voltages in the step currents to obtain a plurality of groups of peak voltage increment corresponding to the step currents one by one, and generating a peak voltage increment curve;
and determining the defect burial depth according to the current value corresponding to the inflection point in the peak voltage increment curve and the preset current and magnetization depth comparison table.
The beneficial effects of the invention are as follows: the magnetic chromatography detection device comprises a direct current magnetizer, an induction coil probe, a power supply module and a signal conditioning module, wherein the direct current magnetizer is controlled by outputting stepped current through the power supply module, the magnetic field intensity of the direct current magnetizer is changed through changing the current, further stepped magnetization of ferromagnetic materials to be detected is realized, the induction coil probe is used for detecting corresponding voltage of magnetic permeability disturbance generated on the upper surface of the ferromagnetic materials to be detected due to internal defects, the defect position is determined according to the detected peak voltage, and the defect buried depth is determined according to the peak voltage increment. The method utilizes the characteristic of peak voltage sudden increase when the internal defect of the ferromagnetic material to be detected is magnetized, analyzes the peak voltage increment, characterizes the defect to be magnetized by the inflection point of the peak voltage increment, and determines the defect buried depth by the current value corresponding to the inflection point and a preset current and magnetization depth comparison table, thereby realizing the accurate detection of the internal defect buried depth of the ferromagnetic material.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following description will briefly explain the drawings needed in the description of the embodiments, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of an embodiment of a magnetic chromatography detection apparatus according to the present invention;
FIG. 2 is a graph showing relative permeability and probe displacement when different magnetizing currents are applied to the upper surface of a ferromagnetic material to be measured in an embodiment of a magnetic chromatography detection apparatus according to the present invention;
FIG. 3 is a graph showing peak voltage values and magnetizing current values of different defect burial depths in an embodiment of a magnetic chromatography detection apparatus according to the present invention;
FIG. 4 is a graph showing the comparison of magnetization current of voltage peak increment and magnetization current of magnetic permeability disturbance of different buried depth defects in an embodiment of a magnetic chromatography detection apparatus according to the present invention;
FIG. 5 is a flow chart of an embodiment of a magnetic chromatography detection method according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be understood that the schematic drawings are not drawn to scale. A flowchart, as used in this disclosure, illustrates operations implemented according to some embodiments of the present invention. It should be appreciated that the operations of the flow diagrams may be implemented out of order and that steps without logical context may be performed in reverse order or concurrently. Moreover, one or more other operations may be added to or removed from the flow diagrams by those skilled in the art under the direction of the present disclosure.
Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the invention. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.
The embodiment of the invention provides a magnetic chromatography detection device and a method, which are respectively described below.
Fig. 1 is a schematic structural diagram of an embodiment of a magnetic chromatography detection apparatus provided by the present invention, as shown in fig. 1, which includes a dc magnetizer 10, an induction coil probe 20, a power module 30 and a signal conditioning module 40;
the direct-current magnetizer 10 and the induction coil probe 20 are arranged on the upper surface of the ferromagnetic material 50 to be measured, the power supply module 30 is respectively connected with the direct-current magnetizer 10, the induction coil probe 20 and the signal conditioning module 40, and the signal conditioning module 40 is connected with the induction coil probe 20;
the dc magnetizer 10 is used for performing step magnetization on the ferromagnetic material 50 to be measured based on the step current output by the power module 30;
the induction coil probe 20 is used for performing defect detection in the process that the ferromagnetic material 50 to be detected is magnetized by steps to obtain a magnetic permeability disturbance detection signal corresponding to the step current;
the signal conditioning module 40 is configured to process the magnetic permeability disturbance detection signal to obtain a peak voltage and a peak voltage increment corresponding to the step current, determine a position of the defect 60 according to the peak voltage, and determine a depth of burial of the defect 60 according to a current value of an inflection point of the peak voltage increment and a preset current and magnetization depth comparison table.
It should be noted that, in the embodiment of the present invention, after the ferromagnetic material 50 to be measured is magnetized, a magnetic field is formed on the upper surface of the ferromagnetic material 50 to be measured, the internal defect 60 of the ferromagnetic material 50 to be measured may generate disturbance to the magnetic field at the corresponding position on the upper surface, the induction coil probe 20 is used to scan the upper surface of the ferromagnetic material to be measured, and the position of the defect 60 relative to the upper surface of the ferromagnetic material 50 to be measured can be determined by the generated change of the detected voltage; since the different magnetization intensities form an unsaturated region in the ferromagnetic material 50 to be measured, if the defect 60 is located in the unsaturated region, the influence of the disturbance of the magnetic field on the upper surface of the ferromagnetic material 50 to be measured by the defect 60 is not great, if the defect 60 is located in the saturated region, the influence of the disturbance of the magnetic field on the upper surface of the ferromagnetic material 50 to be measured is great, and the voltage of the induction coil probe 20 detected at the position corresponding to the upper surface of the internal defect 60 is increased, so the DC magnetizer 10 is controlled by the power module 30 to carry out step magnetization on the ferromagnetic material 50 to be measured, the saturated region is continuously deepened from the upper surface, the moment when the internal defect 60 is changed from the unsaturated region to the saturated region is determined by the peak voltage increment, the step current corresponding to the moment is determined, and the buried depth of the defect 60 is determined according to the magnetization depth corresponding to the step current (i.e. the preset current and magnetization depth comparison table).
It can be understood that, in the embodiment of the present invention, the peak voltage is the voltage detected at the upper surface corresponding to the internal defect 60, when the current input by the power module 30 is the same, the detected voltage at the upper surface corresponding to the internal defect 60 is the maximum relative to other positions of the upper surface, and is the peak voltage, one current value corresponds to one peak voltage, the step currents are the currents sequentially arranged from small to large, the peak voltage increment is the increment obtained by subtracting the peak voltage corresponding to the small current from the peak voltage corresponding to the large current in the two adjacent currents in order, when the internal defect 60 is not magnetized (i.e. the internal defect 60 is in the unsaturated zone), each peak voltage increment should be approximately the same, when a certain current is input, the difference between the peak voltage corresponding to the current and the peak voltage corresponding to the last current is significantly larger than other peak voltage increments, which indicates that the internal defect 60 is magnetized, and the depth of burial of the internal defect 60 is the magnetization depth corresponding to the input current; the preset current and magnetization depth comparison table is obtained by testing a plurality of ferromagnetic materials with different buried depths of the defect 60, and under the condition that the buried depths of the defect 60 are known, the input current corresponding to the inflection point of the peak voltage increment is measured, and the correspondence table of the input current and the buried depths of the defect 60 can be obtained through multiple tests.
It should be noted that, in the embodiment of the present invention, during detection, the static magnetization field is excited by the dc magnetizer 10, the magnitude of the current output by the power module 30 is gradually increased to form a step effect, the internal magnetization degree of the ferromagnetic material 50 to be detected is changed by the step magnetization, an unsaturated magnetization region is formed in the ferromagnetic material 50 to be detected, and the thickness direction of the ferromagnetic material 50 to be detected is layered by the unsaturated region generated by the step magnetization, when the ferromagnetic material 50 to be detected has the internal defect 60, the magnetic line is disturbed above the defect 60 to cause a magnetic field disturbance, so that the region above the defect 60 generates a larger range of magnetic permeability disturbance and is diffused to the upper surface layer of the ferromagnetic material 50 to be detected corresponding to the position of the internal defect 60, the magnetic permeability characteristic different from that of the defect 60 is presented, along with the increase of the magnetization degree, the defect 60 starts to generate the magnetic field distortion to cause the fluctuation of the magnetic permeability of the upper surface of the member, and then the magnetic field disturbance caused by the defect 60 is converted into a voltage signal by the induction coil probe 20.
It should be noted that, in the embodiment of the present invention, the step current output by the power module 30 may be controlled by a current control program provided by the power module 30, or may be manually controlled, the current flowing into the dc magnetizer 10 is increased at intervals according to the time actually required for scanning the upper surface of the ferromagnetic material 50 to be measured by the probe, so as to form a step current, and the magnitude of the current value flowing into the dc magnetizer is fed back to the signal conditioning module 40, so that the signal conditioning module 40 corresponds the defect detection result to the step current one by one, and the step current may be increased in equal amount or in unequal amount, for example, the step current may be divided by layering the magnetization depths according to the magnetization depths.
Compared with the prior art, the magnetic chromatography detection device provided by the invention comprises a direct current magnetizer 10, an induction coil probe 20, a power supply module 30 and a signal conditioning module 40, wherein the direct current magnetizer 10 is controlled by outputting stepped current through the power supply module 30, the magnetic field intensity of the direct current magnetizer 10 is changed by changing the current, further the stepped magnetization of the ferromagnetic material 50 to be detected is realized, the induction coil probe 20 is adopted to detect the corresponding voltage of the magnetic permeability disturbance generated by the internal defect 60 on the upper surface of the ferromagnetic material 50 to be detected, the position of the defect 60 is determined according to the detected peak voltage, and the buried depth of the defect 60 is determined according to the peak voltage increment. The invention utilizes the characteristic of peak voltage sudden increase when the internal defect 60 of the ferromagnetic material 50 to be detected is magnetized, the inflection point of the peak voltage increment is used for representing that the defect 60 is magnetized by analyzing the peak voltage increment, and the embedded depth of the defect 60 is determined by the current value corresponding to the inflection point and the comparison table of the preset current and the magnetized depth, so that the accurate detection of the embedded depth of the internal defect 60 of the ferromagnetic material is realized.
In some embodiments of the present invention, the induction coil probe 20 includes an excitation coil and a detection coil;
the exciting coil is used for exciting a magnetic field on the surface layer of the ferromagnetic material 50 to be tested;
the detection coil is used for detecting the magnetic permeability change condition of the ferromagnetic material 50 to be detected in the magnetization direction and generating a corresponding magnetic permeability disturbance detection signal.
It will be appreciated that in the embodiment of the present invention, the power module 30 may output not only the step current but also the alternating current to the exciting coil, so that the exciting coil excites the magnetic field on the surface layer of the ferromagnetic material 50 to be measured.
In some embodiments of the present invention, the dc magnetizer 10 is a yoke magnetizer composed of a U-shaped ferromagnetic body 12 and a pass-through coil 11.
In some embodiments of the present invention, the pass-through coil 11 is connected to the power module 30, and both yokes of the U-shaped ferromagnetic body 12 are vertically disposed on the upper surface of the ferromagnetic material 50 to be tested.
In some embodiments of the present invention, the dc magnetizer 10 is a pass-through dc coil magnetizer.
It can be understood that, in the embodiment of the present invention, the corresponding relation between the relative permeability and the depth and the position of the defect 60 is also tested through a simulation experiment, and the tested permeability is distorted in the simulation because the upper surface of the steel plate is located at the connecting part between the air and the steel material, so that a two-dimensional truncated line of 0.05mm is arranged on the upper surface of the steel plate to replace the permeability disturbance detection signal extracted from the upper surface of the steel plate, when the defect 60 is moved, different magnetizing currents are introduced, and the corresponding permeability disturbance detection signals of each magnetizing current are summed together to form fig. 2, and fig. 2 enumerates the change of the permeability disturbance detection signals corresponding to different magnetizing currents when the depth s of the defect 60 is 5mm, 10mm, 15mm and 20mm, and the probe displacement is the position of the induction coil probe 20 on the upper surface of the steel plate, for example: when the magnetization current is 6A, the surface layer detects that magnetic permeability disturbance is generated, when the magnetization current reaches 8A, the magnetic permeability disturbance of the defect 60 generates sudden change, at the moment, the defect 60 part is magnetized, the magnetized defect 60 generates a magnetic permeability disturbance field and diffuses to the surface to be detected, and finally, when the magnetization current is 8A, the phenomenon that the magnetic permeability disturbance generates sudden change can be verified, and the magnetization depth is 10mm; as can be seen from the above simulation experiment, the internal defect 60 affects the magnetic permeability of the upper surface, and the different magnetizing currents and the degree of influence of the magnetic permeability are different, so that the change of the magnetic permeability can be reflected by the voltage, and further the detection of the embedded depth of the defect 60 can be realized, and FIG. 3 is a graph of the peak voltage and the magnetizing current value (i.e. the ladder current) of different defect embedded depths, and as can be seen from FIG. 3, the maximum peak value is provided when the ladder current is 1A and indicates that the defect 60 is embedded in 0mm, and when the defect 60 is embedded in 5mm, the maximum peak value is 4A and indicates that the defect 60 is embedded in 5mm, and thus the embedded depth of the defect 60 corresponding to each ladder current can be obtained.
It will be appreciated that the present invention compares the magnetizing current of each buried defect voltage peak increment with the magnetizing current of the magnetic permeability disturbance, and as shown in FIG. 4, acquires the magnetizing current by using the induction coil probe 20 after inputting the stepped magnetizing currentVoltage signals corresponding to each magnetizing current value (namely, step current) are defined, and voltage signal peak values generated by adjacent current values are subtracted: subtracting the peak voltage of the small current from the peak voltage of the large current to obtain the peak voltage increment of the small currentIncrement the peak value of the signal to +.>The point of the trend change is the inflection point, the magnetization current value corresponding to the inflection point is recorded as magnetization current value +.>The point where each defect causes the magnetic permeability disturbance curve to be abrupt is designated as the layer magnetization current +.>Obtaining a group of signals of each buried depth defect under different currents by scanning the surface through a probe, and extracting the peak increment of the signals>Magnetization current value corresponding to inflection point of (2)>. Magnetizing current value +.>Magnetization current disturbed by permeability->Comparison results in FIG. 4 showing the inflection point magnetization current +_for the peak voltage delta change of the magnetic permeability perturbation detection signal detected by the induction coil probe 20>Magnetization current of abrupt point of disturbance of magnetic permeability>The variation is substantially uniform, and thusIt is concluded that the magnetizing current corresponding to each buried defect is different, and the magnetizing current of the defect can be obtained by using the step magnetization, so that the defect position corresponding to each magnetizing current is determined, and the final end parts of the two magnetizing current curves are smooth because the magnetization is close to saturation. When the magnetizing current is increased, the corresponding internal magnetizing depth interval of the steel plate is increased under the same magnetizing current.
Fig. 5 is a schematic flow chart of an embodiment of a magnetic chromatography detection method provided by the present invention, and referring to fig. 5, the present invention further provides a magnetic chromatography detection method applied to a magnetic chromatography detection apparatus, including:
s501, outputting a step current through a power module to control a direct current magnetizer to carry out step magnetization on a ferromagnetic material to be detected;
s502, performing defect detection by adopting an induction coil probe in the process that the ferromagnetic material to be detected is magnetized by a step to obtain a magnetic permeability disturbance detection signal corresponding to the step current;
s503, processing the magnetic permeability disturbance detection signal based on the signal conditioning module to obtain peak voltage and peak voltage increment corresponding to the step current, determining the defect position according to the peak voltage, and determining the defect buried depth according to the current value of the inflection point of the peak voltage increment and a comparison table of preset current and magnetization depth.
In some embodiments of the present invention, before step S401, the method further includes:
and performing magnetization test on ferromagnetic materials with different defect buries to obtain a preset current and magnetization depth comparison table.
In some embodiments of the present invention, step S501 includes:
step current gradually increasing is output to the direct current magnetizer through the power supply module;
the direct current magnetizer carries out step magnetization with gradually increased magnetization intensity on the ferromagnetic material to be tested according to the step current.
In some embodiments of the present invention, step S502 includes:
scanning the upper surface of the ferromagnetic material to be tested along the axial direction of the ferromagnetic material to be tested by adopting an induction coil probe in the process of magnetizing the ferromagnetic material to be tested by steps to obtain a plurality of groups of voltage value sets corresponding to the step currents one by one;
and generating a magnetic permeability disturbance detection signal according to the multiple groups of voltage value sets.
In some embodiments of the present invention, step S503 includes:
generating a plurality of groups of probe displacement voltage curves corresponding to the ladder currents one by one according to the magnetic permeability disturbance detection signals;
determining a plurality of groups of peak voltages according to the plurality of groups of probe displacement voltage curves and determining defect positions according to probe positions corresponding to the peak voltages;
calculating the difference value of peak voltages corresponding to adjacent voltages in the step currents to obtain a plurality of groups of peak voltage increment corresponding to the step currents one by one, and generating a peak voltage increment curve;
and determining the defect buried depth according to the current value corresponding to the inflection point in the peak voltage increment curve and a preset current and magnetization depth comparison table.
It should be understood that, for other embodiments of a magnetic chromatography detection method provided by the present invention, reference may be made to the above-mentioned embodiments of the magnetic chromatography detection apparatus, and details thereof are omitted herein.
The present invention is not limited to the above-mentioned embodiments, and any changes or substitutions that can be easily understood by those skilled in the art within the technical scope of the present invention are intended to be included in the scope of the present invention.
Claims (10)
1. The magnetic chromatography detection device is characterized by comprising a direct current magnetizer, an induction coil probe, a power supply module and a signal conditioning module;
the direct-current magnetizer and the induction coil probe are arranged on the upper surface of the ferromagnetic material to be detected, the power supply module is respectively connected with the direct-current magnetizer, the induction coil probe and the signal conditioning module, and the signal conditioning module is connected with the induction coil probe;
the direct current magnetizer is used for carrying out step magnetization on the ferromagnetic material to be tested based on the step current output by the power supply module;
the induction coil probe is used for carrying out defect detection in the process that the ferromagnetic material to be detected is magnetized by steps to obtain a magnetic permeability disturbance detection signal corresponding to the step current;
the signal conditioning module is used for processing the magnetic permeability disturbance detection signal to obtain peak voltage and peak voltage increment corresponding to the ladder current, determining a defect position according to the peak voltage, and determining defect burial depth according to a current value of an inflection point of the peak voltage increment and a comparison table of preset current and magnetization depth.
2. The magnetic chromatography detection apparatus of claim 1, wherein the induction coil probe comprises an excitation coil and a detection coil;
the exciting coil is used for exciting a magnetic field on the surface layer of the ferromagnetic material to be detected;
the detection coil is used for detecting the magnetic permeability change condition of the ferromagnetic material to be detected in the magnetization direction and generating a corresponding magnetic permeability disturbance detection signal.
3. The magnetic chromatography detection apparatus according to claim 1, wherein the dc magnetizer is a yoke magnetizer composed of a U-shaped ferromagnetic body and a passing-through coil.
4. A magnetic chromatography detection apparatus according to claim 3, wherein the penetrating coil is connected to the power module, and two yokes of the U-shaped ferromagnetic body are vertically disposed on the upper surface of the ferromagnetic material to be detected.
5. The magnetic chromatography detection apparatus of claim 1, wherein the dc magnetizer is a pass-through dc coil magnetizer.
6. A magnetic chromatography detection method, characterized by being applied to the magnetic chromatography detection apparatus according to any one of claims 1 to 5, comprising:
the power module outputs a step current to control the direct current magnetizer to carry out step magnetization on the ferromagnetic material to be tested;
performing defect detection by adopting an induction coil probe in the process that the ferromagnetic material to be detected is magnetized by steps to obtain a magnetic permeability disturbance detection signal corresponding to the step current;
and processing the magnetic permeability disturbance detection signal based on a signal conditioning module to obtain peak voltage and peak voltage increment corresponding to the step current, determining a defect position according to the peak voltage, and determining the defect burial depth according to the current value of the inflection point of the peak voltage increment and a comparison table of preset current and magnetization depth.
7. The method for detecting magnetic chromatography according to claim 6, wherein before the step magnetizing of the ferromagnetic material to be detected is performed by the step current control dc magnetizer outputted by the power module, the method further comprises:
and performing magnetization test on ferromagnetic materials with different defect buries to obtain the preset current and magnetization depth comparison table.
8. The method for detecting magnetic chromatography according to claim 7, wherein the step magnetizing of the ferromagnetic material to be detected by the dc magnetizer controlled by the step current output from the power module comprises:
outputting the step current which gradually increases to the direct current magnetizer through the power supply module;
and the direct current magnetizer carries out the step magnetization of which the magnetization intensity is increased gradually on the ferromagnetic material to be tested according to the step current.
9. The method for detecting magnetic chromatography according to claim 8, wherein the defect detection performed by the induction coil probe during the step magnetization of the ferromagnetic material to be detected to obtain the magnetic permeability disturbance detection signal corresponding to the step current comprises:
scanning the upper surface of the ferromagnetic material to be tested along the axial direction of the ferromagnetic material to be tested by adopting an induction coil probe in the process of magnetizing the ferromagnetic material to be tested in a step manner to obtain a plurality of groups of voltage value sets corresponding to the step currents one by one;
and generating the magnetic permeability disturbance detection signal according to the multiple groups of voltage value sets.
10. The method of claim 9, wherein the processing the magnetic permeability disturbance detection signal based on the signal conditioning module to obtain the peak voltage and the peak voltage increment corresponding to the step current, determining the defect position according to the peak voltage, and determining the defect burial depth according to the current value of the inflection point of the peak voltage increment and a preset current and magnetization depth comparison table comprises:
generating a plurality of groups of probe displacement voltage curves corresponding to the ladder currents one by one according to the magnetic permeability disturbance detection signals;
determining a plurality of groups of peak voltages according to the plurality of groups of probe displacement voltage curves and determining the defect positions according to probe positions corresponding to the peak voltages;
calculating the difference value of the peak voltages corresponding to adjacent voltages in the step currents to obtain a plurality of groups of peak voltage increment corresponding to the step currents one by one, and generating a peak voltage increment curve;
and determining the defect burial depth according to the current value corresponding to the inflection point in the peak voltage increment curve and the preset current and magnetization depth comparison table.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410075246.9A CN117589862B (en) | 2024-01-18 | 2024-01-18 | Magnetic chromatography detection device and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410075246.9A CN117589862B (en) | 2024-01-18 | 2024-01-18 | Magnetic chromatography detection device and method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN117589862A true CN117589862A (en) | 2024-02-23 |
| CN117589862B CN117589862B (en) | 2024-05-17 |
Family
ID=89916998
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410075246.9A Active CN117589862B (en) | 2024-01-18 | 2024-01-18 | Magnetic chromatography detection device and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117589862B (en) |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000227421A (en) * | 1999-02-08 | 2000-08-15 | Nkk Corp | Eddy current examination |
| JP2005257701A (en) * | 2000-01-20 | 2005-09-22 | Jfe Steel Kk | Method and apparatus for measuring material characteristics of magnetic substance material |
| KR20060004713A (en) * | 2004-07-06 | 2006-01-16 | 한국원자력연구소 | Apparatus and method for detecting defect with magnetic flux inducted by ac magnetic field |
| KR20080070292A (en) * | 2007-01-26 | 2008-07-30 | (주)노바마그네틱스 | Defective detector of metal object using an alternating magnetic field |
| CN102590328A (en) * | 2012-02-14 | 2012-07-18 | 厦门大学 | Permanent magnetic and alternating current direct current composite magnetic flux leakage detecting method |
| CN102759567A (en) * | 2012-07-18 | 2012-10-31 | 南昌航空大学 | Eddy current testing recognition and evaluation method for defects of inner wall and outer wall of steel pipe under direct current magnetization |
| CN103149272A (en) * | 2013-02-28 | 2013-06-12 | 厦门大学 | Sub-saturated time-division and multi-frequency magnetic flux leakage testing method |
| JP2016197085A (en) * | 2015-04-06 | 2016-11-24 | 新日鐵住金株式会社 | Magnetic flaw detection method |
| CN113376247A (en) * | 2021-07-21 | 2021-09-10 | 西南石油大学 | Novel composite excitation multi-extension-direction defect leakage magnetic field detection method |
-
2024
- 2024-01-18 CN CN202410075246.9A patent/CN117589862B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000227421A (en) * | 1999-02-08 | 2000-08-15 | Nkk Corp | Eddy current examination |
| JP2005257701A (en) * | 2000-01-20 | 2005-09-22 | Jfe Steel Kk | Method and apparatus for measuring material characteristics of magnetic substance material |
| KR20060004713A (en) * | 2004-07-06 | 2006-01-16 | 한국원자력연구소 | Apparatus and method for detecting defect with magnetic flux inducted by ac magnetic field |
| KR20080070292A (en) * | 2007-01-26 | 2008-07-30 | (주)노바마그네틱스 | Defective detector of metal object using an alternating magnetic field |
| CN102590328A (en) * | 2012-02-14 | 2012-07-18 | 厦门大学 | Permanent magnetic and alternating current direct current composite magnetic flux leakage detecting method |
| CN102759567A (en) * | 2012-07-18 | 2012-10-31 | 南昌航空大学 | Eddy current testing recognition and evaluation method for defects of inner wall and outer wall of steel pipe under direct current magnetization |
| CN103149272A (en) * | 2013-02-28 | 2013-06-12 | 厦门大学 | Sub-saturated time-division and multi-frequency magnetic flux leakage testing method |
| JP2016197085A (en) * | 2015-04-06 | 2016-11-24 | 新日鐵住金株式会社 | Magnetic flaw detection method |
| CN113376247A (en) * | 2021-07-21 | 2021-09-10 | 西南石油大学 | Novel composite excitation multi-extension-direction defect leakage magnetic field detection method |
Non-Patent Citations (6)
| Title |
|---|
| ATHANASIOS KYRGIAZOGLOU ET AL.: "ECT simulation and measurements in ferromagnetic tube using DC homogeneous magnetic field", NONDESTRUCTIVE TESTING AND EVALUATION, vol. 37, no. 2, 21 July 2021 (2021-07-21), pages 229 - 243 * |
| ZHIYANG DENG ET AL.: "A Thickness Reduction Detection Method Based on Magnetic Permeability Perturbation Under DC Magnetization for Ferromagnetic Components", IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, vol. 71, 17 October 2022 (2022-10-17), pages 6006713 - 1 * |
| ZHIYANG DENG ET AL.: "A thickness reduction testing method for ferromagnetic materials based on variable intensity DC magnetization", NDT AND E INTERNATIONAL, no. 138, 17 June 2023 (2023-06-17), pages 102895 - 1 * |
| ZHIYANG DENG ET AL.: "Magnetic Permeability Perturbation Testing Based on Unsaturated DC Magnetization for Buried Defect of Ferromagnetic Materials", JOURNAL OF NONDESTRUCTIVE EVALUATION, vol. 41, 3 November 2022 (2022-11-03), pages 76 - 1 * |
| 戴光 等: "基于脉冲涡流检测的管道腐蚀仿真与实验研究", 化工设备与管道, vol. 53, no. 2, 30 April 2016 (2016-04-30), pages 63 - 66 * |
| 杨理践 等: "钢板脉冲涡流检测方法", 仪表技术与传感器, no. 7, 31 December 2011 (2011-12-31), pages 87 - 90 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN117589862B (en) | 2024-05-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Sun et al. | A new NDT method based on permanent magnetic field perturbation | |
| US9304108B2 (en) | Quenching depth measurement method and quenching depth measurement apparatus | |
| Yang et al. | Multi-layer magnetic focusing sensor structure for pulsed remote field eddy current | |
| CN105092696B (en) | A kind of low-frequency ac flux-leakage detection method for the detection of ferromagnetic pipeline inner surface cracks | |
| Ge et al. | Analysis of signals for inclined crack detection through alternating current field measurement with a U-shaped probe | |
| KR101746072B1 (en) | Nondestructive inspection apparatus for ferromagnetic steam generator tubes and method thereof | |
| Cheng | Nondestructive testing of back-side local wall-thinning by means of low strength magnetization and highly sensitive magneto-impedance sensors | |
| Okolo et al. | Axial magnetic field sensing for pulsed magnetic flux leakage hairline crack detection and quantification | |
| CN117589862B (en) | Magnetic chromatography detection device and method | |
| CN105784839A (en) | Method for detecting micro-defects on surfaces of metal container | |
| Yanfei et al. | A new detection method of the surface broken wires of the steel wire rope using an eddy current differential probe | |
| Zhou et al. | Feasibility study of fatigue damage detection of strands using magnetostrictive guided waves | |
| RU2493561C1 (en) | Eddy current magnetic method of failure detection of ferrous objects | |
| JP2013170910A (en) | Carburization depth measuring method and device | |
| Wu et al. | A novel magnetic testing method for the loss of metallic cross-sectional area of bridge cables | |
| Ge et al. | New parameters for the ACFM inspection of different materials | |
| Yang et al. | Skin effect in eddy current testing with bobbin coil and encircling coil | |
| Göktepe | Investigation of Bx and By components of the magnetic flux leakage in ferromagnetic laminated sample | |
| Mukherjee et al. | Phase sensitive detection of extent of corrosion in steel reinforcing bars using eddy currents | |
| CN205656166U (en) | Nearly surperficial small crack detection device of pressure -bearing equipment | |
| Wang et al. | A new system for defects inspection of boiler water wall tubes using a combination of EMAT and MFL | |
| Lu et al. | Study on low frequency AC excitation magnetic flux leakage testing for defects with different depths | |
| Ma et al. | Research on pipeline internal stress detection technology based on the Barkhausen effect | |
| KR101138359B1 (en) | Nondestructive inspection apparatus generating gradient electromagnetic field | |
| Fukuoka et al. | Flaw detection for microcrack in spring steel and estimation of crack shape with eddy current testing |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |