SU1462173A1 - Magnetic-television device for checking pipe-lines - Google Patents

Abstract

The invention can be used for flaw detection and control of the surface structure of ferromagnetic objects, in particular underground pipelines. The purpose of the invention is to increase the reliability of control due to the possibility of detecting defects of different orientations. For this, the magnetizing system 1 consists of a set of protruding poles with switchable DC windings installed on the central toroidal magnetic circuit inside the pipeline 2 and located on the circumference of the latter. By alternately feeding the series-connected windings of opposite pole pairs formed by the control unit 10 of direct current pulses of a predetermined size, duration and time shift, the magnetizing system 1 creates a magnetic field moving around the circumference of the pipeline 2. Due to this, using the matrix converter 3, you have a different orientation The defects in the pipeline 2, information about which, after selection in the amplitude selector 4, is recorded in blocks 5,6 of dynamic and long-term memory. 5 il. S (L 4a about: to "vl with

Description

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The invention relates to non-destructive testing and can be used for flaw detection and control of the surface structure of ferromagnetic objects, namely, underground trunk pipelines.

The purpose of the invention is to increase the reliability of control due to the possibility of detecting defects of different orientations.

Fig. 1 is a block diagram of the device J in Fig. 2, a cross section of the magnetizing system; on-scan of the magnetizing system in Fig. 4, a block diagram of the control unit i in Fig. 5 is a wiring diagram of the magnetizing system windings and electronic switches.

The device contains a magnetizing system 1, designed to be placed inside the pipeline 2, a series-connected matrix magnetically sensitive converter 3, an amplitude selector 4 and a dynamic memory unit 5, a non-volatile memory unit 6 intended to be connected to the video control unit 7, the unit 8 sweep, the output of which is connected to the control input of the converter 3, the second inputs of the memory blocks 5 and 6, and is intended to be connected to the second input of the video monitor unit 7, and in series nnye power unit 9 and the control unit 10, which is in the form poskh1edovatelno connected shaper 11 pulses, shift register 12, block 13 and block current generators 14 electronic keys. The magnetizing system is made in the form of a toroidal magnetic circuit 15 with a series of p radially protruding poles 16 and DC windings 17 arranged on them connected to the output of the key block 14.

The block 13 of current formers is made in the form of n formers of an FT torrent,. . , FT „, and the block 14 of electronic keys is from 2n pairwise-including electronic keys К, ..., К. The inputs of the current transformers of the FT, .. FTC are connected to the outputs of the shift register 12, and the outputs - to the control inputs of electronic switches K.., K, The magnetizing system 1 contains n switched pairs of opposite poles, the windings of which

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The device works as follows.

The device moves inside the conduit 2.

In the control unit 10, powered by the power supply unit 9, with the help of the driver of 11 pulses, the shift register 12 and the forwarders of the FT currents,. . .FT, the necessary amplitude, duration and time shift of the direct current pulses are formed, which are alternately via electronic keys. To, ..., To the block 14 are fed to the terminals of series-connected windings of opposite pairs of poles P, ..., P magnetizing , system 1. As a result, the magnetizing system 1 creates a magnetic field moving around the circumference of the pipe due to discrete and periodic rotation of the magnetic flux within the circular sections of the lateral surface of the pipeline 2 (FIG. 3).

So, when alternately supplying DC pulses of a current transformer of FT, FT, FTJ via electronic switches K, K, K to series-connected windings of opposite pairs of poles P, P, P, Lj-Lg, Lj-L) - The current rotates along the side surface of the pipe discretely through 360 / 2p angles, scanning the area enclosed within the inner circumference L-La-LjrL -Lg-Li -L. Further, when excited, P, P, P & (, L5 - L, Lg-Lrf) pairs of poles are similarly supplied by means of FT, FT5, FTb formers and electronic keys K ,, 5 K, Kg; the inner circumference of b-bd-bb-bd-b-b-c (Fig. 3). Scanning continues in a similar manner and further along the remaining circles (P pairs of poles are placed within each circle). As a result, a magnetic relief is formed in magnetizing system 1 in conduit 2, containing information on variously oriented defects occurring on the lateral surface of conduit 2. This information is due to the change in the direction of the magnetic flux and its movement around the circumference.

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Claims (2)

bp 2 when switching poles The magnetic relief is fixed by means of a matrix magnetically sensitive transducer 3, placed between the inner side surface of piping 2 and the poles 16 of the magnetizing system 1, and at the output of the transducer 3 electrical signals are proportional to the magnetic field intensity at each point of the scanned surface of the pipe. These signals are fed to the input of the amplitude selector 4, which selects only those signals that correspond to defective points on the surface of the pipeline 2. From the output of the selector 4, signals are input to the block 5 of the dynamic memory. When the volume of the block 5 is filled from its output, information is transmitted to the input of the block 6 of the non-volatile memory and recorded therein. The scanning unit 8 performs a horizontal scanning of the electropotential relief of the matrix converter 3, memory blocks 5 and 6, as well as the electron beam of the video monitoring unit 7. Video monitoring unit 7 is used and included in the device circuit only in ground conditions - to reproduce the image of defects. To do this, after passing the set distance, the device is removed to the surface. Invention Formula Magnetic television device for control of pipelines containing ten 15 621 D 20 25 0 734 a magnetizing magnetizing system, a magnetically sensitive matrix converter and an amplitude selector connected in series, a scanner whose output is connected to the control input of a magnetosensitive converter, a long-term memory unit and a video monitoring unit intended for connection to a long-term memory unit, differ from the fact that In order to increase the reliability of the control, it is equipped with a block of dynamic memory connected between the output of the amplitude selector and the input of the block memory and serially connected power supply and control unit, made in the form of serially connected pulse shaper, shift register, current shaper block and electronic key block, the output of the scanner is connected to the second inputs of the dynamic and long-term memory blocks and is designed for is connected to the second input of the video monitoring unit, and the magnetizing system is also designed as a toroidal magnetic conductor for installation inside the pipeline with a series of radial on protruding poles and windings are placed on the DC-connected to the output of the electronic key block it. 77 FIG. 2  L7 jrr®n L (n 3) Ln L (n-) CPU-5} L (n-2) Fig.Z