CN206876632U

CN206876632U - GMR detection means based on vertical alternative excitation

Info

Publication number: CN206876632U
Application number: CN201720728447.XU
Authority: CN
Inventors: 邱惠昌; 王立玢; 王东祥
Original assignee: Tianjin Optical Electrical Communication Technology Co Ltd
Current assignee: Tianjin Optical Electrical Communication Technology Co Ltd
Priority date: 2017-06-21
Filing date: 2017-06-21
Publication date: 2018-01-12
Anticipated expiration: 2027-06-21

Abstract

The utility model provides a kind of GMR detection means based on vertical alternative excitation, described device includes form excitation coil, platelet group and detection plate, the platelet group includes multiple GMR platelets placed vertically and a collet, multiple GMR platelets are vertically fixed on collet, GMR is provided with the GMR platelets, the amplifying circuit and filter circuit being sequentially connected respectively with each GMR are provided with the detection plate, post position card in the upper surface of the form excitation coil bottom, the GMR platelets group is placed on position card upper surface vertically, the detection plate is placed in form excitation coil outer.The utility model beneficial effect：Crack detection sensitivity, accuracy of detection and detection speed are effectively improved, it is simple in construction, easy to operate.

Description

GMR detection means based on vertical alternative excitation

Technical field

The utility model belongs to current vortex field of non destructive testing, more particularly, to a kind of GMR based on vertical alternative excitation (Giant Magneto Resistive, giant magnetoresistance) detection means.

Background technology

The detection for being present in the crackle of measured material surface or deep layer is an important application of current vortex Non-Destructive Testing Aspect, the precision of detection depend not only on the sensitivity of stimulation level and detection unit, also depend on current vortex in detection test specimen Angle between crackle.Because the angle between excitation orientation and defect is unknown, single direction excitation, which differs, surely to be reached Highest detection sensitivity, optimal detection direction can not be pre-configured with.

Meanwhile traditional scanning along the line takes longer, the detection essence of the magnetic induction intensity of scanning step influence slit region Degree, and to avoid changing in scanning process the lift-off distance of magnetic induction intensity sensor, it is necessary to utilize motor control operation platform Scanned along carrying out, be unfavorable for the crack detection at scene.

Utility model content

In view of this, the utility model is directed to a kind of GMR detection means based on vertical alternative excitation, using vertical Alternate energisation mode is to improve the detection sensitivity of the crackle on measured material surface or deep layer.

To reach above-mentioned purpose, what the technical solution of the utility model was realized in：

GMR detection means based on vertical alternative excitation, including form excitation coil, platelet group and detection plate are described small Plate group includes multiple GMR platelets placed vertically and a collet, and multiple GMR platelets are vertically fixed on collet, described GMR is provided with GMR platelets, the amplification electricity being sequentially connected respectively with each GMR is provided with the detection plate Position card is posted in road and filter circuit, the upper surface of the form excitation coil bottom, and the GMR platelets group is placed in place vertically Card upper surface is put, the detection plate is placed in form excitation coil outer.

Further, it is placed in parallel upwards in row between multiple GMR platelets.

Further, the GMR platelets number is 4.

Further, the form excitation coil length of side is isometric.

Further, the amplifying circuit includes low-power instrument amplifier.

Further, the filter circuit includes voltage feedback type amplifier.

Further, the position card is marked with the test position of rectangular matrix.

Relative to prior art, the GMR detection means described in the utility model based on vertical alternative excitation has following Advantage：

(1) the GMR detection means described in the utility model based on vertical alternative excitation can improve splits to unknown direction The detection sensitivity of line.

(2) the GMR detection means described in the utility model based on vertical alternative excitation can shorten detection time, without electricity Machine control operation platform, realize live rapid crack detection.

(3) GMR platelets group described in the utility model can improve accuracy of detection, reduce the body of magnetic induction intensity sensor Product.

Brief description of the drawings

Form a part of accompanying drawing of the present utility model to be used for providing further understanding to of the present utility model, this practicality is new The schematic description and description of type is used to explain the utility model, does not form to improper restriction of the present utility model. In accompanying drawing：

Fig. 1 is the top view that the GMR platelets group described in the utility model embodiment is combined with position card；

Fig. 2 is the circuit diagram being connected in GMR platelets and detection plate described in the utility model embodiment with this GMR platelet；

The defects of Fig. 3 is described in the utility model embodiment direction schematic diagram；

Fig. 4, which is No. 1 defect, to be detected data fusion color rank with GMR during 90 ° of x-axis angle and schemes；

Fig. 5, which is No. 3 defects, to be detected data fusion color rank with GMR during 90 ° of x-axis angle and schemes；

Fig. 6, which is No. 5 defects, to be detected data fusion color rank with GMR during 90 ° of x-axis angle and schemes；

Fig. 7, which is No. 1 defect, to be detected data fusion color rank with GMR during 45 ° of x-axis angle and schemes；

Fig. 8, which is No. 1 defect, to be detected data fusion color rank with GMR during 30 ° of x-axis angle and schemes；

Fig. 9, which is No. 3 defects, to be detected data fusion color rank with GMR during 45 ° of x-axis angle and schemes；

Figure 10, which is No. 3 defects, to be detected data fusion color rank with GMR during 30 ° of x-axis angle and schemes.

Description of reference numerals：

A-GMR platelets；B- collets；C- positions card.

Embodiment

It should be noted that in the case where not conflicting, the feature in embodiment and embodiment in the utility model can To be mutually combined.

Describe the utility model in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

As depicted in figs. 1 and 2, the GMR detection means based on vertical alternative excitation, including form excitation coil, platelet group And detection plate, the platelet group includes multiple GMR platelets A placed vertically and collet a B, multiple GMR platelets A are vertical It is fixed on collet B, GMR is provided with the GMR platelets, is provided with the detection plate and is sensed respectively with each GMR The amplifying circuit and filter circuit that device is sequentially connected, the circuit part of GMR in circuit is individually extracted, this be for Reduce lift-off distance as far as possible, flexibly place GMR；Post position card, the GMR in the upper surface of the form excitation coil bottom Platelet group is placed on position card upper surface vertically, and the detection plate is placed in form excitation coil outer.

It is placed in parallel upwards in row between multiple GMR platelets.

The GMR platelets number is 4.

The form excitation coil length of side is isometric, is caused avoiding problems coil length and width to analyzing vertical alternative excitation mode Influence, in the present embodiment, the form excitation coil parameter is as shown in table 1.

The form excitation coil parameter of table 1

The amplifying circuit includes low-power instrument amplifier, and the concrete model used in the present embodiment is INA118.

The filter circuit includes voltage feedback type amplifier, and the concrete model used in the present embodiment is AD8055.

The position card C is marked with 1 to No. 16 test position, and these test positions are demarcated with 2*8 matrix form, this reality Apply in example, the row that GMR platelets group is placed on to No. 15 test position vertically first are upward.

To reduce lift-off distance as far as possible, avoid producing magnetic effect, collet B and position card C use thin hardboard.

The detection process of the present embodiment is as follows：

A. form excitation coil is positioned over above the crackle of measured piece, and form excitation coil bottom be close to measured piece with Improve the excitation density of slit region and reduce lift-off distance；

B. on an excitation orientation, 4 road GMR output signals are completed in extraction；

C. after 4 road GMR output signals are completed in each extraction, GMR platelets group, which changes, once monitors position, until completing The data extraction of one group of 8*8GMR detection arrays under one excitation orientation；

D. change excitation orientation, on the excitation orientation selected in step B, complete second group of GMR detection array Data extraction；

E. analysis fusion finally is carried out to two groups of detection data, to analyze the direction of crackle and dimension information.

The position of measured piece and the form excitation coil immobilizes during whole test experience.

Vertical alternative excitation mode, it is using measured piece as plane, exciting current is first along some direction in plane to test specimen Enter row energization, it is to be extracted complete stable magnetic induction intensity data after, change excitation orientation, exciting current is swashed perpendicular to original The sense of current is encouraged, after extracting magnetic induction intensity data again, completes once completely excitation process.In the process of crack monitoring It is central, due to needing whole sprouting and the expansion process of monitoring crack, monitoring system need to carry out test specimen it is continuous not between Disconnected monitoring, therefore driving source will complete multiple complete excitation process.Over time, the multigroup complete excitation mistake of system acquisition The detection data of journey, the judgement to crack position, size and spread scenarios is realized through data analysis contrast.

Due to needing the magnetic induction intensity of extraction vertical direction in test experience, GMR sensitive direction of principal axis need to be along Vertical Square To, it is therefore desirable to GMR platelet groups are vertically placed on inside excitation coil.

In the present embodiment, it is 300*235*5mm by the use of aluminium sheet as measured piece, its size, is lacked with rectangle present on aluminium sheet Fall into and replace crackle to share eight rectangle defects on aluminium sheet, its specific size is shown in Table 2 as study on monitoring object.

The flaw size table of table 2

As shown in figure 3, rotating aluminium sheet, it is respectively 90 °, 45 ° and 30 ° to make defect and x-axis angle, coil bottom surface exciting current Encouraged twice along x-axis and y-axis direction respectively.No. 1, No. 3 and No. 5 is drawn when defect and x-axis angle are 90 °, 45 ° and 30 ° The 8*8GMR detection data fusion color rank figures of defect, the exponent number of color range figure is 30, as shown in Fig. 4 to Figure 10, heavy black line in figure Represent actual defects.

The lateral profile of defect is can be seen that by GMR detection data fusion color rank figures, due to GMR detection data fusion color rank figures The data message of two excitation orientations is contained, length and the position of defect can be estimated simultaneously by it.Color range figure after fusion can To show the border in the direction of defect and defect long side both ends, so as to estimate the direction of defect and length.Pass through Carry out data fusion to the GMR detection signals under two excitation orientations, the defects of two excitation orientations can be integrated information, more have Beneficial to the positions and dimensions of analyzing defect.

Preferred embodiment of the present utility model is the foregoing is only, it is all at this not to limit the utility model Within the spirit and principle of utility model, any modification, equivalent substitution and improvements made etc., the utility model should be included in Protection domain within.

Claims

1. the GMR detection means based on vertical alternative excitation, it is characterised in that：Including form excitation coil, platelet group and detection Plate, the platelet group include multiple GMR platelets placed vertically and a collet, and multiple GMR platelets are vertically fixed on bottom In support, GMR is provided with the GMR platelets, is provided with the detection plate and is sequentially connected respectively with each GMR Amplifying circuit and filter circuit, the upper surface of the form excitation coil bottom posts position card, and the GMR platelets group is vertical Position card upper surface is placed on, the detection plate is placed in form excitation coil outer.

2. the GMR detection means according to claim 1 based on vertical alternative excitation, it is characterised in that：Multiple GMR It is placed in parallel upwards in row between platelet.

3. the GMR detection means according to claim 1 or 2 based on vertical alternative excitation, it is characterised in that：The GMR Platelet number is 4.

4. the GMR detection means according to claim 1 based on vertical alternative excitation, it is characterised in that：The rectangle swashs It is isometric to encourage the coil length of side.

5. the GMR detection means according to claim 1 based on vertical alternative excitation, it is characterised in that：The amplification electricity Road includes low-power instrument amplifier.

6. the GMR detection means according to claim 1 based on vertical alternative excitation, it is characterised in that：The filtered electrical Road includes voltage feedback type amplifier.

7. the GMR detection means according to claim 1 based on vertical alternative excitation, it is characterised in that：The position card It is marked with the test position of rectangular matrix.