SU1681226A1 - Magnetic television fault finder and tuning sample therefor - Google Patents

Abstract

The invention relates to non-destructive testing of materials and products and can be used in mechanical engineering when visualizing the distribution of defects by detecting magnetic fields. The purpose of the invention is to increase the reliability of control by automating the operability and sensitivity of the flaw detector. The magnetically sensitive node 1 scans the surface of the sample 10. The resulting video signal is fed through the comparator 7 to the block 8 of the account. At the beginning of each line, in block 8, the maximum value is recorded, which changes under the action of pulses from comparator 7. Depending on the sensitivity of the device, digital sensitivity 4 highlights the sensitivity of the device in millimeters of the depth of defects. At the same time, vertical stripes are formed on the screen of the video-integrated unit, the number of which depends on the obtained sensitivity of the device. 2 sp.f-ly, 2 ill. w Ё

Description

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The invention relates to non-destructive testing of materials and products and can be used in mechanical engineering when visualizing the distribution of defects by detecting magnetic fields.

The aim of the invention is to increase the reliability of control by automating the operability and sensitivity of the flaw detector.

FIG. 1 shows the flow chart of the flaw detector; in fig. 2 - sample design for verification of a flaw detector.

The flaw detector (Fig. 1) contains a series-connected matrix converter 1, a signal processing unit 2, a video monitoring unit 3 and a digital indicator 4 connected to the output of the signal processing unit 2.

In addition, the flaw detector contains a unit 5 sweeps connected to the matrix transducer 1 and the video monitoring unit 3, and the circuit 6 accounts.

The counting circuit 6 comprises a series-connected comparator 7 connected to the signal processing unit 2 and the counting and conversion unit 8, the output of which is connected to the digital indicator 4, and a control circuit 9 connected between the output of the sweep unit 5 and the second input of the counting and conversion unit 8 codes.

FIG. 1 also shows a sample 10 located near the matrix Converter 1.

Sample 10 (Fig. 2) contains a plate

11 of an electrically conductive material, on which grooves 12.1-12.N are made. Each groove has a fixed depth, which is determined by an arithmetic progression

hk hi + Ah- (k-1), where hk is the depth of the k-ro slot 12.k;

hi is the depth of the first groove 12.1; Ah- step of changing the depth between adjacent grooves.

The distance between adjacent grooves

12 is fixed and determined from the condition of exceeding the resolution of the device.

The device works as follows.

Sample 10 is located near the matrix converter 1. In the control mode, the input of the comparator 7 is connected to the output of the signal processing unit 2. Scanning unit 5 using a matrix converter 1 sequentially scans

sample 10 surface. After conversion in signal processing unit 2, video signal is converted in comparator 7 into a digital signal controlling the operation of counting unit 8. On commands from the control circuit 9, the counting unit 8 is preset and read the number of registered pulses within one line. Since the depth of the grooves 12 is fixed and calibrated in millimeters,

then by the number of pulses recorded by digital indicator 4, the minimum depth of the detected defect is unambiguously determined.

Additional information in the form

the image is recorded on the screen of the video monitoring unit 3.

Claims (2)

1. A magnetotelevision flaw detector containing a series-connected matrix converter, a signal processing unit and a video monitoring unit, a digital indicator connected to the signal processing unit, and a scanning unit connected to the matrix converter and video monitoring unit, characterized in that it is equipped with a counting circuit, made in the form of serially connected control circuit, connected to the scanner, the counting unit and code conversion, connected to the digital indicator, and a comparator connected between the output of the signal processing unit and the second input of the counting unit and code conversion. 2. A tuning sample for a magneto-physical flaw detector containing a plate of an electrically conductive laterial with a calibrated defect in the form of a groove, characterized in that it is provided with additional grooves arranged parallel to the main groove, the depth of each groove is fixed and varies in comparison with the previous groove by arithmetic progression, and the distance between adjacent grooves is constant. FIG. 2