RU2245542C2 - Method for magnetic control and device for realization of said method - Google Patents

Abstract

FIELD: non-destructive control technologies.

SUBSTANCE: object is magnetized and relief of magnetic dispersion field by rotation of object table base with object placed on it, between poles of U-shaped magnet, scanning of magnetic field relief is performed by rotation of object table base with samples on it, between poles of magnetization means and two string sets of magnetic-sensitive elements. Conversion of magnetic dispersion field to electric signal is performed and information is read by compensation method due to fact, that axes of sensitivity of magnetic-sensitive elements of upper set and lower set are directed oppositely to each other. Device has magnetization means, magnetic-sensitive converter, reading means, information processing means and defects visualization means, object table with base. Examined object is placed on table base. Table base is mounted with possible rotation between poles of magnetization means and two identical parallel-placed string sets of magnetic-sensitive elements. Each sensitive element of upper set matches sensitive element of lower set, and sensitivity axes thereof are directed oppositely to each other.

EFFECT: higher trustworthiness and reliability of defects identification.

2 cl, 3 dwg

Description

The invention relates to the field of non-destructive magnetographic inspection of products and samples of any shape, material and state of aggregation in mass production in order to identify the spatial position of defects, assess their shape, orientation, as well as measure their geometric dimensions (length, depth, opening).

There is a method of non-destructive testing of oil and gas pipelines, implemented in an in-tube magnetic shell of an introscope [1].

It includes magnetizing the product, scanning the relief of the magnetic field of the scattering of the product, converting the magnetic field of the scattering into an electrical signal, reading, processing information and visualizing defects.

The known method does not provide the possibility of magnetographic control of products and samples of any shape, material and state of aggregation in mass production.

The closest analogue to the proposed technical solution is the method and the magnetic control of pipes implemented using its device [2].

A known prototype of the method includes the magnetization of the product; scanning the relief of the magnetic field scattering of the product; conversion of the scattering magnetic field into an electrical signal; reading, processing of information and visualization of defects.

The known method and implemented using its device does not provide control of products and samples of any shape, material and state of aggregation.

The essence of the method of magnetic control of products and samples, including magnetization of the test object, scanning the relief of the magnetic field of scattering, converting the magnetic field of scattering into an electrical signal, reading, processing information and visualizing defects, is that magnetization of the studied object and scanning of the relief of the magnetic field of scattering is carried out by rotation of the worktop of the subject table with the object under study located between the poles of the magnetization means and two lines magnetic sets of magnetically sensitive elements, moreover, the scattering magnetic field is converted and information is read out by the compensation method due to the fact that the sensitivity axes of the magnetically sensitive elements of the upper set and lower set are directed towards each other.

The essence of the device for magnetic control of products and samples containing a magnetization means, a magnetically sensitive transducer, means for reading, processing information and visualizing defects, consists in the fact that it contains an object table with a tabletop on which the studied object is mounted, mounted for rotation between the poles of the means magnetization and two identical parallel-located lowercase sets of magnetically sensitive elements of the magnetically sensitive transducer, one which are installed above the countertop and the other under the countertop, with each magnetically sensitive element of the upper set corresponding to a magnetically sensitive element of the lower set, and their axis of sensitivity directed towards each other, while lowercase sets of magnetically sensitive elements are stationary, and the magnetization means contains two magnets connected by a flexible magnetic circuit installed with the possibility of their vertical movement to regulate the gap between their poles, upper and lower st Accurate sets of magnetosensitive elements are also mounted vertically to adjust the gap between them.

The essence of the alleged invention is illustrated by comparing its technical characteristics with the technical characteristics of the prototype.

1. If in the prototype the operations of magnetization and scanning are separated in time, then in the proposed technical solution these operations are combined, which reduces the time of control.

2. In the prototype, the magnetosensitive sensor is parallel to the axis of rotation of the product, and in the proposed technical solution it is perpendicular to it. This allows you to control samples of any state of aggregation, placing them directly on a rotating tabletop or in ditches, in the form of homogeneous or heterogeneous mixtures of various materials and state of aggregation.

2. In the prototype, the magnetosensitive sensor consists of one lowercase set of magnetosensitive elements, which allows you to register the characteristics of the scattering magnetic field in absolute values, while registering as an informative signal, and not informative (noise). In the proposed technical solution, two lowercase sets of magnetically sensitive elements are used, which makes it possible to record the characteristics of the scattering magnetic field in relative values, placing them above and below the rotating tabletop. In this case, the vertical geometric axes of the upper set of magnetically sensitive elements of the horizontal transducer coincide with the geometric axes of the lower one, and their sensitivity axes are directed towards each other and compensate for the resulting signal, which eliminates the registration of all non-informative signals. This provides an increase in sensitivity due to the appearance of a reference point relative to which the magnetic characteristics are measured, increasing the signal-to-noise ratio. In general, this leads to an increase in the reliability and reliability of the identification of controlled defects.

The principle of operation of the method and device for magnetic control of products and samples of any shape, material and state of aggregation can be explained using the Hardware-software complex of non-destructive testing APK-NK-2 and drawings.

Figure 1 is a front view of the APK-NK-2.

Figure 2 is a top view of the APK-NK-2.

Figure 3 is a three-dimensional image of the presence of magnetic inclusions in a non-magnetic material.

APK-NK-2 (Figure 1, Figure 2.) includes: a subject table 1; rotating countertop 2; test sample 3; a rack for mounting a magnetizing device 4; a moving pole of the upper magnet 5; a moving pole of the lower magnet 6; flexible magnetic circuit 7; a rack for mounting a magnetically sensitive sensor 8; a sensor of the magnetically sensitive transducer (9, 10, 11, 12), consisting of an upper line set of magnetically sensitive elements of the sensor 9; lower line set of magnetically sensitive elements of the sensor 10; magnetically sensitive elements 11; signal wires 12; information reading means 13; information processing means 14; 3D imaging tool 15.

The control of the sample begins with the rotation of the tabletop 2 mounted on a stationary massive object table 1. The magnetization of the test sample 3, located on a rotating tabletop 2, is carried out using magnetization means (5, 6, 7) mounted on a rack 4, with the possibility of vertical movement poles (5, 6), which are interconnected by a magnetic core 7. Registration of the magnetic field of the scattering of sample 3 is carried out using a magnetically sensitive sensor (9, 10, 11, 12) mounted on a rack 8. The sensor consists of two x sets lowercase magnetosensitive elements (9, 10), with the possibility of vertical movement. The spatial arrangement and electrical connection of the lowercase elements to the reader is designed so that it receives only an informative signal. After the reading means 13, the signal enters the information processing means 14, where the electrical signals are converted to digital form, written to the computer 15 in the form of a digital matrix of numbers, which is decrypted using a specially designed computer program and displayed as a three-dimensional image of the magnetic responses of the controlled image on the display screen (Fig 3).

Sources of information

1. A.A. Abakumov and others. Status and prospects of development of magnetic introscopes for the diagnosis of gas and oil pipelines. "Control. Diagnostics" No. 10, IAEE, Obninsk, 1999, 38.

2. Patent RU No. 2191374, MKI 7 G 01 N 27/85, publ. 10/20/2002, Bull. Number 29.

Claims (4)

1. The method of magnetic control of products and samples, including magnetizing the test object, scanning the relief of the magnetic field of scattering, converting the magnetic field of the scattering into an electrical signal, reading, processing information and visualizing defects, characterized in that the magnetization of the studied object and scanning of the relief of the magnetic field of scattering by rotating the tabletop of the subject table with the object under study located between the poles of the magnetization means and two lowercase abord magnetosensitive elements, and converting the stray magnetic field and reading of information is performed by the compensation method by the fact that the sensitivity axis of the upper set and lower magnetosensitive elements set directed towards each other. 2. A device for magnetic control of products and samples containing a magnetization means, a magnetically sensitive transducer, means for reading, processing information and visualizing defects, characterized in that it contains an object table with a tabletop on which the studied object is mounted, mounted for rotation between the poles of the tool magnetization and two identical parallel-located lowercase sets of magnetically sensitive elements of the magnetically sensitive transducer, one of them to which is installed above the countertop, and the other under the countertop, with each magnetically sensitive element of the upper set corresponds to a magnetically sensitive element of the lower set, and their sensitivity axes are directed towards each other. 3. The device according to claim 2, characterized in that the lower case sets of magnetically sensitive elements are stationary. 4. The device according to claim 2, characterized in that the means of magnetization contains two magnets connected by a flexible magnetic circuit, mounted with the possibility of vertical movement to adjust the gap between their poles, the upper and lower lower case sets of magnetically sensitive elements are also installed with the possibility of vertical movement for regulation the gap between them.

Images