SU1562839A1 - Magnetosensitive unit for magnetic tv flaw detector - Google Patents

Abstract

The invention relates to non-destructive testing methods and can be used to visualize the structure of a control object by recording the distribution of magnetic fields. The aim of the invention is to increase the efficiency of defect detection by increasing the sensitivity of ferrite cores to magnetic fields. When testing a product, ring ferrite cores 1.1-1. N are placed on the surface of the test object. Initially, the current pulses are supplied to the dynamic displacement wire 3, the magnitude of which is selected using a variable resistor 6 specifically for each ring ferrite core. Then a current pulse is supplied to the excitation wire 2 and the information is read out by the output winding 5. Signals from all ring ferrite cores are stored and displayed on a television screen. 1 hp f-ly. 2 Il.

Description

1

The interpretation refers to the methods of non-destructive testing and can be used to visualize the structure of the control object by recording the distribution of magnetic fields. The aim of the invention is to increase the efficiency of defect detection by increasing the sensitivity of ferrite cores to magnetic fields.

FIG. 1 shows the construction of the magician of the Thickening node and its coordination with the magneto-television flaw detector J in FIG. 2 — a magnetically sensitive node, an option.

The magnetically sensitive node (Fig. 1) contains ring-shaped ferrite cores 1.1-1.N with a straight hysteresis loop, arranged in a ruler, excitation wires 2.1-2.N, and dynamic displacement wires 3.1-3.N piercing the corresponding ferrite cores I.1 -1.N, control wire 4 and output winding b, respectively, penetrating all ring ferrite cores 1.

In addition, the magnetically sensitive node contains variable resistors 6.1-6.N connected in series with the corresponding dynamic displacement wires 3.1-3.N and forming, in combination, elements 7.1-7.N of the dynamic displacement.

The device also contains a block 8 scan, the odd outputs of which are connected to the outputs of variables; resistors 6.1-6.N, and even outputs are connected to the corresponding excitation wires 2.1-2.N.

The magneto-television flaw detector 3, which contains a magnetically sensitive node, also includes a series-connected differential amplifier 9 whose input is connected to an output winding 5, a detector 10, an amplitude selector 1 1, an analog-to-digital converter 12, a block 13 of memory, a digital-to-analog converter 14 and a video monitor unit 15 and a serially connected synchronous generator 16, whose input is connected to an analog-to-digital converter 12, and the outputs are connected to a memory block 13, a digital-to-digital vym converter 14 and block 8 sweep, and the current key

0

five

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five

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35

40

45

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17, the output of which is connected to control wire 4.

An embodiment of the magnetically sensitive unit (Fig. 2) also contains additional ferrite cores 17.1-17.N, also located in a ruler, and windings 18.1- 18.N.c. Connecting the corresponding ring ferrite cores 1.1-1. N and ferrite cores 17.1-17.N.

The device works as follows.

Ring ferrite cores 1.1-1.N are placed on the surface of the controlled product (not shown in figure 1). The scanner unit 8, according to the signals of the synchronous generator 16, supplies current pulses to the excitation wires 2.1-2.N, which cause a remagnetization of the ring ferrite cores 1.1-1.N. In this case, a signal is induced in the output winding, which is amplified by a differential amplifier 9, detected by detector 10, extracted from interference by an amplitude selector 11, converted into a digital code, analog-to-digital converter 12 and recorded in memory block 13. After the full frame has been recruited, the information is converted by the digital-to-analog converter 14 into a video signal and displayed on the screen of the video monitoring unit 15. By polling each ring ferrite core -1, it is dynamically shifted by applying a current pulse to the wires 3.1-3.N dynamic offset. The pulse amplitude is chosen specifically for each ring ferrite core 1 with a corresponding variable resistor 6,

When implementing a magnetically sensitive node with two lines of ferrite cores, the dynamic displacement is carried out as follows. The ring ferrite core 1.1 was first polled. When it is magnetized, a current pulse arises, which turns into a bias current in the winding 18.1 of the connection and mixes the ferrite core 17.1. A pulse is then sent from the interrogation to the excitation wire 2.1 and the received signal is read. The process then repeats for the next pair.

51.562839

the form of the invention of the invention

Claims (2)

1. Magnet-sensitive node for a magneto-television flaw detector containing a ruler of ferrite cores with a rectangular hysteresis loop, excitation wires penetrating the corresponding ferrite cores, a control wire and an output winding, penetrating all ferrite cores and a scanner, characterized in that increase the efficiency of defect detection, it is equipped with dynamic displacement elements, / each of which contains a series-connected variable resistor connected minutes corresponding to odd output scanner, and the dynamic biasing wire penetrating respective ferrite core, and an excitation wire connected to the respective outputs of the even-numbered scanning unit. 2. Magnetosensitive node according to claim 1, characterized in that the elements of dynamic displacement made with additional ferrite cores arranged in a ruler, threaded with dynamic displacement wires and a control wire, and with windings bonding, connecting the corresponding ring ferrite cores of the line of ring ferrite cores of the magnetically sensitive node and the line of ferrite cores dynamic displacement. 2M FIG. 2