CN108508093A - A kind of detection method and system of workpiece, defect height - Google Patents

A kind of detection method and system of workpiece, defect height Download PDF

Info

Publication number
CN108508093A
CN108508093A CN201810250129.6A CN201810250129A CN108508093A CN 108508093 A CN108508093 A CN 108508093A CN 201810250129 A CN201810250129 A CN 201810250129A CN 108508093 A CN108508093 A CN 108508093A
Authority
CN
China
Prior art keywords
signal
extreme point
defect
workpiece
measurement
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.)
Pending
Application number
CN201810250129.6A
Other languages
Chinese (zh)
Inventor
王强
原培
吴琳琳
朱凯
李海航
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China Jiliang University
Original Assignee
China Jiliang University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by China Jiliang University filed Critical China Jiliang University
Priority to CN201810250129.6A priority Critical patent/CN108508093A/en
Publication of CN108508093A publication Critical patent/CN108508093A/en
Pending legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04Analysing solids
    • G01N29/06Visualisation of the interior, e.g. acoustic microscopy
    • G01N29/0609Display arrangements, e.g. colour displays
    • G01N29/0645Display representation or displayed parameters, e.g. A-, B- or C-Scan
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B17/00Measuring arrangements characterised by the use of subsonic, sonic or ultrasonic vibrations
    • G01B17/02Measuring arrangements characterised by the use of subsonic, sonic or ultrasonic vibrations for measuring thickness
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00Indexing codes associated with group G01N29/00
    • G01N2291/02Indexing codes associated with the analysed material
    • G01N2291/028Material parameters
    • G01N2291/02854Length, thickness
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00Indexing codes associated with group G01N29/00
    • G01N2291/02Indexing codes associated with the analysed material
    • G01N2291/028Material parameters
    • G01N2291/0289Internal structure, e.g. defects, grain size, texture

Abstract

The present invention discloses a kind of detection method and system of workpiece, defect height, and this method includes:Obtain the D scanning images of the weld seam of workpiece for measurement;The defect and defective locations of workpiece for measurement are determined according to D scanning images;The A at defective locations, which is obtained, according to D scanning images sweeps signal;Signal is swept to A and carries out Wavelet Denoising Method processing, obtains reconstruction signal;Wiener filtering processing is carried out to reconstruction signal, obtains the estimated value of the defect response signal of workpiece for measurement;Inverse Fourier transform is carried out to the estimated value of defect response signal, obtains the time-domain signal of defect response signal;According to time-domain signal, the upper extreme point diffracted signal of defect and the time difference of lower extreme point diffracted signal, the upper extreme point depth of defect, lower extreme point depth are calculated;The height of defect is calculated according to the time difference of upper extreme point depth, lower extreme point depth, upper extreme point and lower extreme point diffracted signal.Defect quantitative error can be effectively reduced using the method for the present invention or system, improve recall rate.

Description

A kind of detection method and system of workpiece, defect height
Technical field
The present invention relates to field of non destructive testing, more particularly to a kind of detection method and system of workpiece, defect height.
Background technology
With the development of non-destructive testing technology, ultrasonic wave diffraction time difference method (Time Of Flight Diffraction, TOFD) application of detection method is also more and more extensive, and compared with traditional supersonic detection method, ultrasonic TOFD has detection speed Faster, detection efficiency is high, and the positioning and quantitative precision higher relative error to defect are smaller, and can record and preserve for a long time The advantages such as data.
Ultrasonic TOFD detection is the time difference propagated according to the diffracted signal that endpoint above and below defect generates to realize flaw height Accurate quantification, influenced by examined workpiece thickness, when thickness of workpiece is relatively thin, ultrasonic TOFD detection A sweep in signal lead directly to wave, Aliasing easily occurs defect for endpoint diffracted wave and Bottom echo up and down, and temporal resolution is caused to reduce.And in the prior art then It is by artificially judging endpoint up and down, and then the height of determining endpoint up and down.A sweeps noise in signal in being detected due to ultrasonic TOFD Presence cause defect upper and lower side diffracted signal to be difficult to differentiate between so that in the prior art to flaw height it is quantitative exist compared with Big error.
Invention content
The object of the present invention is to provide a kind of detection methods and system of workpiece, defect height, solve ultrasonic TOFD detection The presence that middle A sweeps noise in signal causes defect upper and lower side diffracted signal to be difficult to differentiate between so that flaw height quantitative error is larger The problem of.
To achieve the above object, the present invention provides following schemes:
A kind of detection method of workpiece, defect height, including:
Obtain the D scanning images of the weld seam of workpiece for measurement;The D scannings image by scanner to the weld seam of workpiece for measurement into Row D scannings obtain;
The defective locations of the workpiece for measurement are determined according to the D scannings image;
The A obtained at the defective locations according to the D scannings image sweeps signal;It is the defective bit that the A, which sweeps signal, Set the elevation information at place;
Signal is swept to the A and carries out Wavelet Denoising Method processing, obtains reconstruction signal;
Wiener filtering processing is carried out to the reconstruction signal, obtains the estimation of the defect response signal of the workpiece for measurement Value;
Inverse Fourier transform is carried out to the estimated value of the defect response signal, obtains the defect response of the workpiece for measurement The time-domain signal of signal;
According to the time-domain signal, the upper extreme point diffracted signal and lower extreme point diffraction letter of the defect of the workpiece for measurement are calculated Number time difference, the defect upper extreme point depth, lower extreme point depth;
According to the time difference of the upper extreme point depth, the lower extreme point depth, the upper extreme point and lower extreme point diffracted signal The height of the defect is calculated.
Optionally, described that signal progress Wavelet Denoising Method processing is swept to the A, it obtains reconstruction signal and specifically includes:
According to wavelet transformation formulaTo the A It sweeps signal to be decomposed, obtains radio-frequency component and low-frequency component that the A sweeps signal;Wherein, ψ (t) is mother wavelet function, will be female Wavelet function scale stretches and is obtained after translatingA is scale factor, and b is shift factor, ψ* a,b (t) it is ψa,b(t) conjugation, y (t) are that A sweeps signal;
By the radio-frequency component zero setting, the low-frequency component remains unchanged, and obtains filtering signal;
Wavelet inverse transformation is carried out to the filtering signal to reconstruct to obtain the reconstruction signal.
Optionally, described that Wiener filtering processing is carried out to the reconstruction signal, obtain the defect response of the workpiece for measurement The estimated value of signal specifically includes:
Fourier transformation, the reconstruction signal after being converted are carried out to the reconstruction signal;Reconstruct letter after the transformation It number is expressed as:G (t)=X (t) * H (t)+N (t);Wherein, G (t) is the reconstruction signal after the transformation, and X (t) is after converting Ultrasound enters workpiece signal, and H (t) is the defect response signal of the workpiece for measurement after transformation, and N (t) is the noise signal after transformation;
According to formulaWiener filtering is carried out to the reconstruction signal after the transformation, is obtained To the estimated value of the defect response signal of the workpiece for measurement, wherein G (t) is the reconstruction signal after the transformation, X*(t) it is X (t) conjugation, Snn(t) be n (t) power spectral density function, Shh(t) be h (t) power spectral density function, h (t) be it is to be measured The defect response signal of workpiece, n (t) is noise signal, by Snn(t)/Shh(t) it is set as 0.01 | X (t)max|2
Optionally, the upper extreme point diffracted signal and lower extreme point diffraction letter that the defect is calculated according to the time-domain signal Number time difference, the defect upper extreme point depth, lower extreme point depth specifically include:
Obtain the propagation time t of the upper extreme point diffracted signal of the defect1
Obtain the propagation time t of the lower extreme point diffracted signal of the defect2
According to formula Δ t=t2-t1Calculate the time difference of the upper extreme point diffracted signal and lower extreme point diffracted signal;
According to formulaCalculate the upper extreme point depth, wherein d1For the upper extreme point depth;
According to formulaCalculate the lower extreme point depth;Wherein, d2For the lower extreme point depth, c is Spread speed of the longitudinal wave in the workpiece for measurement, s are the ultrasonic wave transmitting probe and receiving transducer centre-to-centre spacing of the scanner From half.
Optionally, described to be believed according to the upper extreme point depth, the lower extreme point depth, the upper extreme point and lower extreme point diffraction Number time difference the height of the defect be calculated be specially:
According to formulaThe height of the defect is calculated, In, d1For upper extreme point depth, d2For lower extreme point depth, c is spread speed of the longitudinal wave in the workpiece for measurement, and s is the scanning The half of the ultrasonic wave transmitting probe and receiving transducer centre distance of device, t1For the propagation of the upper extreme point diffracted signal of the defect Time, Δ t are the time difference of the upper extreme point diffracted signal and lower extreme point diffracted signal.
A kind of detecting system of workpiece, defect height, including:
D scanning image collection modules, the D scanning images of the weld seam for obtaining workpiece for measurement;The D scannings image is by sweeping Device is looked into obtain the weld seam progress D scannings of workpiece for measurement;
Defect determining module, the defective locations for determining the workpiece for measurement according to the D scannings image;
A sweeps signal acquisition module, and the A for being obtained at the defective locations according to the D scannings image sweeps signal;It is described It is the elevation information at the defective locations that A, which sweeps signal,;
Wavelet Denoising Method module carries out Wavelet Denoising Method processing for sweeping signal to the A, obtains reconstruction signal;
Filter module, for carrying out Wiener filtering processing to the reconstruction signal, the defect for obtaining the workpiece for measurement is rung The estimated value of induction signal;
Time-domain signal acquisition module carries out inverse Fourier transform for the estimated value to the defect response signal and obtains institute State the time-domain signal of the defect response signal of workpiece for measurement;
Endpoint computing module, for according to the time-domain signal, calculating the upper extreme point diffraction of the defect of the workpiece for measurement The time difference of signal and lower extreme point diffracted signal, the upper extreme point depth of the defect, lower extreme point depth;
Height computing module, for according to the upper extreme point depth, the lower extreme point depth, the upper extreme point and lower extreme point The height of the defect is calculated in the time difference of diffracted signal.
Optionally, the Wavelet Denoising Method module specifically includes:
Wavelet transform unit, for according to wavelet transformation formula Signal is swept to the A to decompose, and obtains radio-frequency component and low-frequency component that the A sweeps signal;Wherein, ψ (t) is morther wavelet letter Number, after mother wavelet function scale is stretched and translatedA is scale factor, b be translation because Son, ψ* a,b(t) it is ψa,b(t) conjugation, y (t) are that A sweeps signal;
High frequency removal unit is used for the radio-frequency component zero setting, and the low-frequency component remains unchanged, and obtains filtering letter Number;
Signal reconstruction unit reconstructs to obtain the reconstruction signal for carrying out wavelet inverse transformation to the filtering signal.
Optionally, the filter module specifically includes:
Fourier transform unit, for carrying out Fourier transformation, the reconstruction signal after being converted to the reconstruction signal; Reconstruction signal after the transformation is expressed as:G (t)=X (t) * H (t)+N (t);Wherein, G (t) is the reconstruct letter after the transformation Number, X (t) is that the ultrasound after transformation enters workpiece signal, and H (t) is the defect response signal of the workpiece for measurement after transformation, and N (t) is Noise signal after transformation;
Estimated value computing unit, for according to formulaTo the reconstruct after the transformation Signal carries out Wiener filtering, obtains the estimated value of the defect response signal of the workpiece for measurement, wherein G (t) is after the transformation Reconstruction signal, X*(t) be X (t) conjugation, Snn(t) be n (t) power spectral density function, Shh(t) be h (t) power spectrum Density function, h (t) are the defect response signal of workpiece for measurement, and n (t) is noise signal, by Snn(t)/Shh(t) it is set as 0.01 |X(t)max|2
Optionally, the endpoint computing module specifically includes:
Upper extreme point time acquisition unit, the propagation time t of the upper extreme point diffracted signal for obtaining the defect1
Lower extreme point time acquisition unit, the propagation time t of the lower extreme point diffracted signal for obtaining the defect2
Time difference calculating unit, for according to formula Δ t=t2-t1It calculates the upper extreme point diffracted signal and lower extreme point spreads out Penetrate the time difference of signal;
Upper extreme point depth calculation unit, for according to formulaThe upper extreme point depth is calculated, In, d1For the upper extreme point depth;
Lower extreme point depth calculation unit, for according to formulaCalculate the lower extreme point depth;Its In, d2For the lower extreme point depth, c is spread speed of the longitudinal wave in the workpiece for measurement, and s is the ultrasonic wave of the scanner The half of transmitting probe and receiving transducer centre distance.
Optionally, the height computing module is specially:
According to formulaThe height of the defect is calculated, In, d1For upper extreme point depth, d2For lower extreme point depth, c is spread speed of the longitudinal wave in the workpiece for measurement, and s is the scanning The half of the ultrasonic wave transmitting probe and receiving transducer centre distance of device, t1For the propagation of the upper extreme point diffracted signal of the defect Time, Δ t are the time difference of the upper extreme point diffracted signal and lower extreme point diffracted signal.
According to specific embodiment provided by the invention, the invention discloses following technique effects:
The present invention obtains D scanning images, and then the A for obtaining defect sweeps signal, to A by carrying out D scannings to workpiece for measurement It sweeps signal and carries out wavelet transformation and Wiener filtering, and then obtain accurate flaw height.By wavelet transformation and wiener in the present invention Filtering, which is combined, improves ultrasonic TOFD flaw height quantitative accuracy, can be good at inhibiting the noise in signal, removal ultrasound A sweeps the noise signal of signal in TOFD detections, improves temporal resolution, reduces the height quantitative error of defect, improves defect inspection Extracting rate realizes the accurate quantification of flaw height, has actual engineering application value.
Description of the drawings
It in order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, below will be to institute in embodiment Attached drawing to be used is needed to be briefly described, it should be apparent that, the accompanying drawings in the following description is only some implementations of the present invention Example, for those of ordinary skill in the art, without having to pay creative labor, can also be according to these attached drawings Obtain other attached drawings.
Fig. 1 is the detection method flow chart of workpiece, defect height of the embodiment of the present invention;
Fig. 2 is the detecting system module map of workpiece, defect height of the embodiment of the present invention.
Specific implementation mode
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete Site preparation describes, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other Embodiment shall fall within the protection scope of the present invention.
The object of the present invention is to provide a kind of detection methods and system of workpiece, defect height, solve ultrasonic TOFD detection The presence that middle A sweeps noise in signal causes defect upper and lower side diffracted signal to be difficult to differentiate between so that flaw height quantitative error is larger The problem of.
In order to make the foregoing objectives, features and advantages of the present invention clearer and more comprehensible, below in conjunction with the accompanying drawings and specific real Applying mode, the present invention is described in further detail.
Fig. 1 is the detection method flow chart of workpiece, defect height of the embodiment of the present invention.Referring to Fig. 1, a kind of workpiece, defect is high The detection method of degree, including:
Step 101:Obtain the D scanning images of the weld seam of workpiece for measurement;The D scannings image is by scanner to workpiece for measurement Weld seam carry out D scannings obtain;
Step 102:The defective locations of the workpiece for measurement are determined according to the D scannings image;
Step 103:The A obtained at the defective locations according to the D scannings image sweeps signal;The A sweeps signal as institute State the elevation information at defective locations;
Step 104:Signal is swept to the A and carries out Wavelet Denoising Method processing, obtains reconstruction signal;
Step 105:Wiener filtering processing is carried out to the reconstruction signal, obtains the defect response signal of the workpiece for measurement Estimated value;
Step 106:Inverse Fourier transform is carried out to the estimated value of the defect response signal, obtains the workpiece for measurement The time-domain signal of defect response signal;
Step 107:According to the time-domain signal, upper extreme point diffracted signal and the lower end of the defect of the workpiece for measurement are calculated The point time difference of diffracted signal, the upper extreme point depth of the defect, lower extreme point depth;
Step 108:According to the upper extreme point depth, the lower extreme point depth, the upper extreme point and lower extreme point diffracted signal Time difference the height of the defect is calculated.
Ultrasonic TOFD flaw height quantitative accuracy can be improved using the above method, can be good at inhibiting making an uproar in signal Sound, A sweeps the noise signal of signal in removal ultrasonic TOFD detection, improves temporal resolution, reduces the height quantitative error of defect, Defect detection rate is improved, realizes the accurate quantification of flaw height.
It wherein first has to determine the information such as workpiece for measurement material, thickness before step 101, be selected according to workpiece for measurement information Suitable frequency probe, size and angle are selected, ultrasonic wave transmitting probe and two center probe spacing (PCS) of receiving transducer are calculated, Ultrasonic wave transmitting probe and receiving transducer spacing on scanner are adjusted, and it is symmetrically placed on to examined workpiece weld seam both sides, super The relevant parameters such as PCS, emitting voltage, detecting way, repetition rate are set on sound TOFD survey meters, Scanning sensitivity is set; Scanner is pushed to carry out D scannings to workpiece for measurement weld seam then along with weld seam parallel direction.
Wherein step 104 specifically includes:
According to wavelet transformation formulaTo the A It sweeps signal to be decomposed, obtains radio-frequency component and low-frequency component that the A sweeps signal;Wherein, ψ (t) is mother wavelet function, will be female Wavelet function scale stretches and is obtained after translatingA is scale factor, and b is shift factor, ψ* a,b (t) it is ψa,b(t) conjugation, y (t) are that A sweeps signal;
By the radio-frequency component zero setting, the low-frequency component remains unchanged, and obtains filtering signal;
Wavelet inverse transformation is carried out to the filtering signal to reconstruct to obtain the reconstruction signal.
Step 105 specifically includes:
Fourier transformation, the reconstruction signal after being converted are carried out to the reconstruction signal;Reconstruct letter after the transformation It number is expressed as:G (t)=X (t) * H (t)+N (t);Wherein, G (t) is the reconstruction signal after the transformation, and x (t) is that ultrasound enters Workpiece signal, h (t) are the defect response signal of workpiece for measurement, and n (t) is noise signal, and X (t) is that the ultrasound after transformation enters work Part signal, H (t) are the defect response signal of the workpiece for measurement after transformation, and N (t) is the noise signal after transformation;
According to formulaWiener filtering is carried out to the reconstruction signal after the transformation, is obtained To the estimated value of the defect response signal of the workpiece for measurement, wherein G (t) is the reconstruction signal after the transformation, X*(t) it is X (t) conjugation, Snn(t) be n (t) power spectral density function, Shh(t) be h (t) power spectral density function, by Snn(t)/Shh (t) it is set as 0.01 | X (t)max|2
Step 107 specifically includes:
Obtain the propagation time t of the upper extreme point diffracted signal of the defect1
Obtain the propagation time t of the lower extreme point diffracted signal of the defect2
According to formula Δ t=t2-t1Calculate the time difference of the upper extreme point diffracted signal and lower extreme point diffracted signal;
According to formulaCalculate the upper extreme point depth, wherein d1For the upper extreme point depth;
According to formulaCalculate the lower extreme point depth;Wherein, d2For the lower extreme point depth, c is Spread speed of the longitudinal wave in the workpiece for measurement, s are the ultrasonic wave transmitting probe and receiving transducer centre-to-centre spacing of the scanner From half.
Step 108 is specially:
According to formulaThe height of the defect is calculated, In, d1For upper extreme point depth, d2For lower extreme point depth, c is spread speed of the longitudinal wave in the workpiece for measurement, and s is the scanning The half of the ultrasonic wave transmitting probe and receiving transducer centre distance of device, t1For the propagation of the upper extreme point diffracted signal of the defect Time, Δ t are the time difference of the upper extreme point diffracted signal and lower extreme point diffracted signal.
Fig. 2 is the detecting system module map of workpiece, defect height of the embodiment of the present invention.Referring to Fig. 2, a kind of workpiece, defect is high The detecting system of degree, including:
D scannings image collection module 201, the D scanning images of the weld seam for obtaining workpiece for measurement;The D scannings image D scannings are carried out by scanner to the weld seam of workpiece for measurement to obtain;
Defect determining module 202, the defective locations for determining the workpiece for measurement according to the D scannings image;
A sweeps signal acquisition module 203, and the A for being obtained at the defective locations according to the D scannings image sweeps signal; It is the elevation information at the defective locations that the A, which sweeps signal,;
Wavelet Denoising Method module 204 carries out Wavelet Denoising Method processing for sweeping signal to the A, obtains reconstruction signal;
Filter module 205 obtains the defect of the workpiece for measurement for carrying out Wiener filtering processing to the reconstruction signal The estimated value of response signal;
Time-domain signal acquisition module 206 carries out inverse Fourier transform for the estimated value to the defect response signal and obtains To the time-domain signal of the defect response signal of the workpiece for measurement;
Endpoint computing module 207, for according to the time-domain signal, the upper extreme point for calculating the defect of the workpiece for measurement to spread out Penetrate the time difference of signal and lower extreme point diffracted signal, the upper extreme point depth of the defect, lower extreme point depth;
Height computing module 208, for according to the upper extreme point depth, the lower extreme point depth, the upper extreme point and under The height of the defect is calculated in the time difference of endpoint diffracted signal.
Ultrasonic TOFD flaw height quantitative accuracy can be improved using above system, improve defect detection rate, realize defect The accurate quantification of height has actual engineering application value.
Wherein, Wavelet Denoising Method module 204 specifically includes:
Wavelet transform unit, for according to wavelet transformation formula Signal is swept to the A to decompose, and obtains radio-frequency component and low-frequency component that the A sweeps signal;Wherein, ψ (t) is morther wavelet letter Number, after mother wavelet function scale is stretched and translatedA is scale factor, b be translation because Son, ψ* a,b(t) it is ψa,b(t) conjugation, y (t) are that A sweeps signal;
High frequency removal unit is used for the radio-frequency component zero setting, and the low-frequency component remains unchanged, and obtains filtering letter Number;
Signal reconstruction unit reconstructs to obtain the reconstruction signal for carrying out wavelet inverse transformation to the filtering signal.
The filter module 205 specifically includes:
Fourier transform unit, for carrying out Fourier transformation, the reconstruction signal after being converted to the reconstruction signal; Reconstruction signal after the transformation is expressed as:G (t)=X (t) * H (t)+N (t);Wherein, G (t) is the reconstruct letter after the transformation Number, x (t) is that ultrasound enters workpiece signal, and h (t) is the defect response signal of workpiece for measurement, and n (t) is noise signal, and X (t) is Ultrasound after transformation enters workpiece signal, and H (t) is the defect response signal of the workpiece for measurement after transformation, and N (t) is after converting Noise signal;
Estimated value computing unit, for according to formulaTo the reconstruct after the transformation Signal carries out Wiener filtering, obtains the estimated value of the defect response signal of the workpiece for measurement, wherein G (t) is after the transformation Reconstruction signal, X*(t) be X (t) conjugation, Snn(t) be n (t) power spectral density function, Shh(t) be h (t) power spectrum Density function, by Snn(t)/Shh(t) it is set as 0.01 | X (t)max|2
Endpoint computing module 207 specifically includes:
Upper extreme point time acquisition unit, the propagation time t of the upper extreme point diffracted signal for obtaining the defect1
Lower extreme point time acquisition unit, the propagation time t of the lower extreme point diffracted signal for obtaining the defect2
Time difference calculating unit, for according to formula Δ t=t2-t1It calculates the upper extreme point diffracted signal and lower extreme point spreads out Penetrate the time difference of signal;
Upper extreme point depth calculation unit, for according to formulaThe upper extreme point depth is calculated, In, d1For the upper extreme point depth;
Lower extreme point depth calculation unit, for according to formulaCalculate the lower extreme point depth;Its In, d2For the lower extreme point depth, c is spread speed of the longitudinal wave in the workpiece for measurement, and s is the ultrasonic wave of the scanner The half of transmitting probe and receiving transducer centre distance.
Height computing module 208 is specially:
According to formulaThe height of the defect is calculated, In, d1For upper extreme point depth, d2For lower extreme point depth, c is spread speed of the longitudinal wave in the workpiece for measurement, and s is the scanning The half of the ultrasonic wave transmitting probe and receiving transducer centre distance of device, t1For the propagation of the upper extreme point diffracted signal of the defect Time, Δ t are the time difference of the upper extreme point diffracted signal and lower extreme point diffracted signal.
Each embodiment is described by the way of progressive in this specification, the highlights of each of the examples are with other The difference of embodiment, just to refer each other for identical similar portion between each embodiment.For system disclosed in embodiment For, since it is corresponded to the methods disclosed in the examples, so description is fairly simple, related place is said referring to method part It is bright.
Principle and implementation of the present invention are described for specific case used herein, and above example is said The bright method and its core concept for being merely used to help understand the present invention;Meanwhile for those of ordinary skill in the art, foundation The thought of the present invention, there will be changes in the specific implementation manner and application range.In conclusion the content of the present specification is not It is interpreted as limitation of the present invention.

Claims (10)

1. a kind of detection method of workpiece, defect height, which is characterized in that including:
Obtain the D scanning images of the weld seam of workpiece for measurement;The D scannings image carries out D by scanner to the weld seam of workpiece for measurement Scanning obtains;
The defective locations of the workpiece for measurement are determined according to the D scannings image;
The A obtained at the defective locations according to the D scannings image sweeps signal;It is at the defective locations that the A, which sweeps signal, Elevation information;
Signal is swept to the A and carries out Wavelet Denoising Method processing, obtains reconstruction signal;
Wiener filtering processing is carried out to the reconstruction signal, obtains the estimated value of the defect response signal of the workpiece for measurement;
Inverse Fourier transform is carried out to the estimated value of the defect response signal, obtains the defect response signal of the workpiece for measurement Time-domain signal;
According to the time-domain signal, the upper extreme point diffracted signal and lower extreme point diffracted signal of the defect of the workpiece for measurement are calculated Time difference, upper extreme point depth, lower extreme point depth;
It is calculated according to the time difference of the upper extreme point depth, the lower extreme point depth, the upper extreme point and lower extreme point diffracted signal Obtain the height of the defect.
2. detection method according to claim 1, which is characterized in that described to be swept at signal progress Wavelet Denoising Method to the A Reason, obtains reconstruction signal and specifically includes:
According to wavelet transformation formulaLetter is swept to the A It number is decomposed, obtains radio-frequency component and low-frequency component that the A sweeps signal;Wherein, ψ (t) is mother wavelet function, by morther wavelet Function scale stretches and is obtained after translatingA is scale factor, and b is shift factor, ψ* a,b(t) it is ψa,b(t) conjugation, y (t) are that A sweeps signal;
By the radio-frequency component zero setting, the low-frequency component remains unchanged, and obtains filtering signal;
Wavelet inverse transformation is carried out to the filtering signal to reconstruct to obtain the reconstruction signal.
3. detection method according to claim 1, which is characterized in that described to be carried out at Wiener filtering to the reconstruction signal Reason, obtains the estimated value of the defect response signal of the workpiece for measurement, specifically includes:
Fourier transformation, the reconstruction signal after being converted are carried out to the reconstruction signal;Reconstruction signal table after the transformation It is shown as:G (t)=X (t) * H (t)+N (t);Wherein, G (t) is the reconstruction signal after the transformation, and X (t) is the ultrasound after transformation Into workpiece signal, H (t) is the defect response signal of the workpiece for measurement after transformation, and N (t) is the noise signal after transformation;
According to formulaWiener filtering is carried out to the reconstruction signal after the transformation, obtains institute State the estimated value of the defect response signal of workpiece for measurement, wherein G (t) is the reconstruction signal after the transformation, X*(t) it is X (t) Conjugation, Snn(t) be n (t) power spectral density function, Shh(t) be h (t) power spectral density function, h (t) be work to be measured The defect response signal of part, n (t) is noise signal, by Snn(t)/Shh(t) it is set as 0.01 | X (t)max|2
4. detection method according to claim 1, which is characterized in that described to calculate the defect according to the time-domain signal Upper extreme point diffracted signal and the time difference of lower extreme point diffracted signal, the upper extreme point depth of the defect, lower extreme point depth it is specific Including:
Obtain the propagation time t of the upper extreme point diffracted signal of the defect1
Obtain the propagation time t of the lower extreme point diffracted signal of the defect2
According to formula Δ t=t2-t1Calculate the time difference of the upper extreme point diffracted signal and lower extreme point diffracted signal;
According to formulaCalculate the upper extreme point depth, wherein d1For the upper extreme point depth;
According to formulaCalculate the lower extreme point depth;Wherein, d2For the lower extreme point depth, c is longitudinal wave Spread speed in the workpiece for measurement, s are the ultrasonic wave transmitting probe and receiving transducer centre distance of the scanner Half.
5. detection method according to claim 4, which is characterized in that described according to the upper extreme point depth, the lower end Point depth, the upper extreme point and lower extreme point diffracted signal time difference the height of the defect be calculated be specially:
According to formulaCalculate the height of the defect, wherein d1 For upper extreme point depth, d2For lower extreme point depth, c is spread speed of the longitudinal wave in the workpiece for measurement, and s is the scanner The half of ultrasonic wave transmitting probe and receiving transducer centre distance, t1For the upper extreme point diffracted signal of the defect propagation when Between, Δ t is the time difference of the upper extreme point diffracted signal and lower extreme point diffracted signal.
6. a kind of detecting system of workpiece, defect height, which is characterized in that including:
D scanning image collection modules, the D scanning images of the weld seam for obtaining workpiece for measurement;The D scannings image is by scanner D scannings are carried out to the weld seam of workpiece for measurement to obtain;
Defect determining module, the defective locations for determining the workpiece for measurement according to the D scannings image;
A sweeps signal acquisition module, and the A for being obtained at the defective locations according to the D scannings image sweeps signal;The A is swept Signal is the elevation information at the defective locations;
Wavelet Denoising Method module carries out Wavelet Denoising Method processing for sweeping signal to the A, obtains reconstruction signal;
Filter module obtains the defect response letter of the workpiece for measurement for carrying out Wiener filtering processing to the reconstruction signal Number estimated value;
Time-domain signal acquisition module carries out inverse Fourier transform for the estimated value to the defect response signal and obtains described wait for Survey the time-domain signal of the defect response signal of workpiece;
Endpoint computing module, for according to the time-domain signal, calculating the upper extreme point diffracted signal of the defect of the workpiece for measurement With the time difference of lower extreme point diffracted signal, the upper extreme point depth of the defect, lower extreme point depth;
Height computing module, for according to the upper extreme point depth, the lower extreme point depth, the upper extreme point and lower extreme point diffraction The height of the defect is calculated in the time difference of signal.
7. detecting system according to claim 6, which is characterized in that the Wavelet Denoising Method module specifically includes:
Wavelet transform unit, for according to wavelet transformation formula Signal is swept to the A to decompose, and obtains radio-frequency component and low-frequency component that the A sweeps signal;Wherein, ψ (t) is morther wavelet letter Number, after mother wavelet function scale is stretched and translatedA is scale factor, b be translation because Son, ψ* a,b(t) it is ψa,b(t) conjugation, y (t) are that A sweeps signal;
High frequency removal unit, for by the radio-frequency component zero setting, the low-frequency component to remain unchanged, and obtains filtering signal;
Signal reconstruction unit reconstructs to obtain the reconstruction signal for carrying out wavelet inverse transformation to the filtering signal.
8. detecting system according to claim 6, which is characterized in that the filter module specifically includes:
Fourier transform unit, for carrying out Fourier transformation, the reconstruction signal after being converted to the reconstruction signal;It is described Reconstruction signal after transformation is expressed as:G (t)=X (t) * H (t)+N (t);Wherein, G (t) is the reconstruction signal after the transformation, X (t) enter workpiece signal for the ultrasound after transformation, H (t) is the defect response signal of the workpiece for measurement after transformation, and N (t) is transformation Noise signal afterwards;
Estimated value computing unit, for according to formulaTo the reconstruction signal after the transformation Wiener filtering is carried out, the estimated value of the defect response signal of the workpiece for measurement is obtained, wherein G (t) is the weight after the transformation Structure signal, X*(t) be X (t) conjugation, Snn(t) be n (t) power spectral density function, Shh(t) be h (t) power spectral density Function, h (t) are the defect response signal of workpiece for measurement, and n (t) is noise signal, by Snn(t)/Shh(t) it is set as 0.01 | X (t)max|2
9. detecting system according to claim 6, which is characterized in that the endpoint computing module specifically includes:
Upper extreme point time acquisition unit, the propagation time t of the upper extreme point diffracted signal for obtaining the defect1
Lower extreme point time acquisition unit, the propagation time t of the lower extreme point diffracted signal for obtaining the defect2
Time difference calculating unit, for according to formula Δ t=t2-t1Calculate the upper extreme point diffracted signal and lower extreme point diffraction letter Number time difference;
Upper extreme point depth calculation unit, for according to formulaCalculate the upper extreme point depth, wherein d1For The upper extreme point depth;
Lower extreme point depth calculation unit, for according to formulaCalculate the lower extreme point depth;Wherein, d2 For the lower extreme point depth, c is spread speed of the longitudinal wave in the workpiece for measurement, and s is that the ultrasonic wave of the scanner emits The half of probe and receiving transducer centre distance.
10. detecting system according to claim 6, which is characterized in that the height computing module is specially:
According to formulaCalculate the height of the defect, wherein d1 For upper extreme point depth, d2For lower extreme point depth, c is spread speed of the longitudinal wave in the workpiece for measurement, and s is the scanner The half of ultrasonic wave transmitting probe and receiving transducer centre distance, t1For the upper extreme point diffracted signal of the defect propagation when Between, Δ t is the time difference of the upper extreme point diffracted signal and lower extreme point diffracted signal.
CN201810250129.6A 2018-03-26 2018-03-26 A kind of detection method and system of workpiece, defect height Pending CN108508093A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810250129.6A CN108508093A (en) 2018-03-26 2018-03-26 A kind of detection method and system of workpiece, defect height

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810250129.6A CN108508093A (en) 2018-03-26 2018-03-26 A kind of detection method and system of workpiece, defect height

Publications (1)

Publication Number Publication Date
CN108508093A true CN108508093A (en) 2018-09-07

Family

ID=63378396

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810250129.6A Pending CN108508093A (en) 2018-03-26 2018-03-26 A kind of detection method and system of workpiece, defect height

Country Status (1)

Country Link
CN (1) CN108508093A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109900805A (en) * 2019-04-08 2019-06-18 大连理工大学 Defect quantitative detection method in the blind area TOFD based on frequency-domain sparse inverting

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1804611A (en) * 2005-12-27 2006-07-19 哈尔滨工业大学 Ultrasonic time-of-flight diffraction detection method based on synthetic aperture focusing technique
CN101839895A (en) * 2009-12-17 2010-09-22 哈尔滨工业大学 Near-surface defect recognition method based on ultrasonic TOFD
CN102435675A (en) * 2011-09-23 2012-05-02 南昌航空大学 Ultrasonic TOFD technology detection method for butt seam of different thickness plates
US9109433B2 (en) * 2005-08-01 2015-08-18 Baker Hughes Incorporated Early kick detection in an oil and gas well
CN105973990A (en) * 2015-09-16 2016-09-28 中国核工业二三建设有限公司 Inclined crack TOFD quantitative detection method based on geometric relationship
CN107449829A (en) * 2017-08-09 2017-12-08 上海船舶工程质量检测有限公司 A kind of butt weld Non-Destructive Testing acceptance method
CN107655974A (en) * 2017-09-29 2018-02-02 宁波恒信工程检测有限公司 A kind of TOFD automatic scannings device

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9109433B2 (en) * 2005-08-01 2015-08-18 Baker Hughes Incorporated Early kick detection in an oil and gas well
CN1804611A (en) * 2005-12-27 2006-07-19 哈尔滨工业大学 Ultrasonic time-of-flight diffraction detection method based on synthetic aperture focusing technique
CN101839895A (en) * 2009-12-17 2010-09-22 哈尔滨工业大学 Near-surface defect recognition method based on ultrasonic TOFD
CN102435675A (en) * 2011-09-23 2012-05-02 南昌航空大学 Ultrasonic TOFD technology detection method for butt seam of different thickness plates
CN105973990A (en) * 2015-09-16 2016-09-28 中国核工业二三建设有限公司 Inclined crack TOFD quantitative detection method based on geometric relationship
CN107449829A (en) * 2017-08-09 2017-12-08 上海船舶工程质量检测有限公司 A kind of butt weld Non-Destructive Testing acceptance method
CN107655974A (en) * 2017-09-29 2018-02-02 宁波恒信工程检测有限公司 A kind of TOFD automatic scannings device

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
周红明: "薄材焊缝自动化超声TOFD成像检测关键技术研究", 《中国博士学位论文全文数据库 信息科技辑》 *
曾向阳 著: "《智能水中目标识别》", 31 March 2016, 国防工业出版社 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109900805A (en) * 2019-04-08 2019-06-18 大连理工大学 Defect quantitative detection method in the blind area TOFD based on frequency-domain sparse inverting

Similar Documents

Publication Publication Date Title
CN104007176B (en) Full-wave field detection system and method of complex geotechnical engineering medium
CN103148815B (en) Based on the thickness of thin layer supersonic detection method of sound pressure reflection coefficient autocorrelation function
CN102636568B (en) Finite element ultrasonic imaging method used for detecting defect in concrete
CN104391039A (en) Storage tank bottom plate corrosion noncontact ultrasonic detection method based on dynamic wavelet fingerprint technology
Zhang et al. Monte Carlo inversion of ultrasonic array data to map anisotropic weld properties
CN104698089A (en) Ultrasonic relative time propagation technology suitable for inclined crack quantifying and imaging
CN104634876A (en) Method for detecting inclusions in metal material by virtue of ultrasonic scanning microscope
CN104749253A (en) Ultrasonic back scattering imaging method and device for inner defects of cylindrical workpiece
CN104360046A (en) Comprehensive geophysical-prospecting combined diagnosis method for hidden danger inside wharf concrete structure
Bouden et al. Signal processing methods for materials defects detection
CN104897777A (en) Method for improving longitudinal resolution of TOFD (time of flight diffraction) detection with Burg algorithm based autoregressive spectrum extrapolation technology
JP4591850B2 (en) Ultrasonic inspection method and apparatus
Wiggenhauser Advanced NDT methods for quality assurance of concrete structures
CN109900805A (en) Defect quantitative detection method in the blind area TOFD based on frequency-domain sparse inverting
JP2018084416A (en) Ultrasonic inspection device and ultrasonic inspection method
CN108508093A (en) A kind of detection method and system of workpiece, defect height
CN105044215A (en) Non-destructive material sound velocity field measurement method
CN105403627A (en) Method for enhancing lateral resolution of ultrasonic testing images
KR101082085B1 (en) Ultrasonic imaging device and Method for controlling the same
CN101819182B (en) Method for reconstructing defect shape in non-uniform medium
CN110346453B (en) Method for rapidly detecting reflection echoes of small defect arrays in concrete structure
CN109541689B (en) Method for evaluating compactness of medium based on reflected wave energy characteristics
Cao et al. A correlation-based approach to corrosion detection with Lamb wave mode cutoff
CN102798889B (en) Phased source consistency determining method
Li et al. Research on the imaging of concrete defect based on the pulse compression technique

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