RU2806246C1 - Method of magnetic powder flaw detection and device implementing it - Google Patents

Abstract

FIELD: magnetic powder inspection.

SUBSTANCE: essence of the invention lies in the fact that an electromagnet is installed on the surface of the controlled product with an indicator package fixed in its elastically deformable spring clamps, made of non-magnetic material and filled with a magnetic suspension; exposure to an alternating magnetic field of an electromagnet on a controlled product; detection of an indicator trace of a defect in the form of a roll of magnetic powder in the indicator package as a result of the interaction of the magnetic field with the material of the product in the image control zone; visual observation of this trace on a recording device with increased resolution and its recording in the memory of the microprocessor of the recording device, while the indicator package with an elastic deformable frame supporting it from below is installed with the lower thin elastic side on the controlled area of the surface of the product, and the outer flat elastic deformable side of the package and placed underneath under the bag, the frame is springily installed parallel to the surface of the product being inspected, ensuring the same thickness of the suspension layer in the bag over the entire inspected area of the product.

EFFECT: providing the ability to increase sensitivity, productivity, and reliability of control.

5 cl, 4 dwg

Description

The proposed invention relates to the field of non-destructive quality control of materials and products using the magnetic particle method and is intended for testing parts, products and welded joints made of ferromagnetic materials to identify defects in them such as discontinuities (cracks, sunsets, delaminations, pores, cavities, etc.) on water , air, road and rail transport, in metallurgy, in various fields of mechanical engineering, in oil, gas, chemical, nuclear and other industries, in outer space and underwater facilities.

There is a known method of magnetic particle testing, which consists in magnetizing a product, applying a magnetoscopic indicator (ferromagnetic particles in the form of a suspension or dry powder) directly to its surface and subsequent visual inspection of the resulting indicator image on the surface of this product. If there is a defect on the inspected surface of the product, ferromagnetic particles, when the product is magnetized under the influence of a magnetic scattering field formed above the defect, settle along the boundaries of the defect in the form of an indicator magnetic roller [N.I. Eremin, “Magnetic particle flaw detection”, 1947, ed. Ministry of Heavy Engineering of the USSR, 1947, 152 p. see Ch. III-IV]. Defects are detected visually or using a 2-7x optical magnifier.

When using magnetoluminescent powders, the controlled product is illuminated with ultraviolet light with a wavelength of 300-400 nm. The phosphor, combined with ferromagnetic powder particles, converts ultraviolet radiation energy into visible light, usually in the orange or yellow-green range, which provides high sensitivity control in low daylight [G.S. Shelikhov. Magnetic particle flaw detection of parts and assemblies. Moscow, 1995 p. 125-130, 134-174].

A device for implementing this method is known, containing a power source - a power step-down transformer, a magnetizing device (electromagnet), a current control unit, a magnetization mode measuring system, a magnetoscopic indicator and lighting system [G.S. Shelikhov. Magnetic particle flaw detection of parts and assemblies. Moscow, 1995 p. 112-125].

The disadvantage of the known method and device for its implementation is that the operation of applying a magnetic suspension directly to the surface of the controlled product entails the need to prepare the surface for testing (cleaning and degreasing); there is a large consumption of suspension; in case of repeated inspection of this area of the product, it is necessary to wash the product after the previous inspection to remove residual magnetic powder and dry the product to prevent corrosion damage. All this worsens, in general, the sanitary conditions and safety of control and, ultimately, leads to a decrease in control productivity and significant control costs.

Closer in technical essence to the proposed invention is the magnetic particle flaw detector described in the USSR Author's Certificate No. 557305, G01N 27/84 dated 06/18/77. The flaw detector contains a magnetizing unit formed from two permanent magnets in the form of rollers mounted on bearings on a common axis with a specified distance from each other, depending on the width of the inspection zone; a ring translucent porthole is inserted into one of the rollers; a magnetically sensitive information carrier consisting of a transparent cylinder that rigidly connects both rollers of the magnetizing unit, and a transparent elastic shell covering the outside of the cylinder, in contact with the product being controlled, and the space between the cylinder and the shell is filled with a magnetic suspension; an optical-electronic indicator consisting of a light source, a lens and a video image receiver, rigidly mounted on an axis and interacting with a magnetically sensitive information carrier, and a remote monitoring panel with a display and controls. This flaw detector is applicable for testing ferromagnetic extended products such as rolled products (rails, large-diameter pipes, channels, T-bars, longitudinal welds of pipes and sheets and other long products).

The method of testing with this flaw detector is as follows: The magnetizing unit is installed on the surface being tested. Elements of the optical-electronic indicator - light source, lens and video receiver are oriented towards the control zone located between the rollers. They include an autonomous drive connected to one of the rollers by a flexible shaft. As a result, a magnetizing unit rolling along the controlled surface ensures consistent and continuous magnetization of surface areas in the control zone. The image of the currently monitored area of the product, illuminated by a light source, obtained in suspension on the inner surface of the elastic shell, is transmitted through the cylinder wall, lens, and annular translucent porthole to the video image receiver and then to the display of the remote monitoring panel.

The disadvantages of this method and device are: a limited range of products possible for inspection, it is almost impossible to carry out fluorescent magnetic particle flaw detection due to the strong absorption of ultraviolet light in the thick walls of the cylinder and the ring porthole, low productivity due to the low speed of inspection due to the need for a certain time for deposition of powder and formation of an indicator image in the control zone with continuous displacement of the suspension during rolling of the flaw detector.

A close analogue in the functional design of the magnetic particle flaw detector No. 557305 described above is a digital magnetic flaw detector for testing products using the magnetic particle method according to the PRC patent CN 206920387 U, Int.Cl. G01N 27/84, dated 2018.01.23. The device has a separate equipment housing with a built-in power supply for the entire device, a display and a keyboard with a microprocessor for controlling the operation of the device. The equipment body is connected to an electromagnet designed to magnetize the controlled area of the product. The electromagnet, similar to the flaw detector according to Author's Certificate No. 557305, has light sources (LEDs) and a video camera for monitoring and photographing the controlled area, a button to turn the electromagnet on/off, and, in addition, a device for aerosol spraying of magnetic powder over the controlled area.

The control method with this device consists of installing an electromagnet on the controlled surface of the product; turning on the power of the electromagnet and magnetizing the controlled area of the product; turning on the device for aerosol spraying of magnetic powder over the controlled area and simultaneously with spraying the powder, turning on the video camera to observe and record the formation of an indicator image from the magnetic powder over the defect.

The disadvantages of this device and control method are that aerosol spraying of magnetic powder is negative for the health of the operator, the need to prepare (clean) the controlled surface, which reduces control productivity, high consumption of magnetic powder, and the inability to control underwater objects directly in water and objects in space.

A closer analogue to the claimed device and method is the method and device described in the article by K.G. Walther. "The Magfoil Method", Material Evalution, 1983, vol. 41, no. 5, p. 582-585.

The control method consists of magnetizing the product, placing an indicator package consisting of two parts, in which the magnetic powder and liquid phase are located separately, on the controlled area and then mixing the contents of both parts of the indicator package, as a result of which, if there is a defect in the product, the formation roll of magnetic powder in the area of the defect. Then the mixture is polymerized in an indicator package, and the resulting defectogram serves as documentary confirmation of the control results. The device for implementing this method contains a power supply, an electromagnet and an indicator package.

The described method and device do not require the operation of applying a magnetoscopic indicator (powder or suspension) to the surface of the product, however, they have the disadvantage that the indicator package used in the device is suitable only for one-time use. Each new control operation requires replacing the indicator package with a new one. This increases the consumption of flaw detection materials and also reduces inspection productivity.

The closest in technical essence to the claimed method and device is the magnetic particle testing method taken as a prototype, implemented using a magnetic flaw detector according to RF patent No. 2171984, IPC G01N 27/84 dated 12/15/1998.

To implement this method, an indicator package filled with a high-viscosity magnetic fluid is placed on the surface of the controlled product in the interpolar space of the electromagnet, which acts as a magnetizing device. A flat coil intended for erasing the pattern of the magnetized liquid in the indicator package is pressed from above to the indicator package, while the lower part of the package takes the shape of the surface of the product, and the upper part, pressed against the flat erasing coil, remains flat. The tested product is magnetized with an alternating magnetic field and, through the viewing window in the electromagnet, the formation of an indicator pattern in the form of a bead of magnetic powder above the defect on the bottom side of the package is observed visually in the indicator package in the area of the controlled area of the surface of the product in the presence of a defect. The resulting defectogram serves as the result of testing a given area of the product. For the next inspection cycle (stage), the current in the electromagnet windings is turned off, the flaw detector is removed from the surface of the product, and the current in the coil is turned on, as a result of which the image in the indicator package is erased. Place the flaw detector again on the same (if the inspection needs to be repeated) or on a new area of the product and repeat the inspection operations. If during the testing process the magnetic image in the package begins to lose contrast, the package must be disconnected from the flaw detector and the magnetic fluid must be thoroughly mixed until a homogeneous medium is obtained. If necessary, the indicator package with a magnetic image of the defect can be disconnected from the flaw detector and can serve as documentary evidence of the presence of a defect in the product, since the image in the package, due to the high viscosity of the medium, can be stored for several days, and a new package is used to continue monitoring.

A flaw detector that implements this method includes a power supply, an electromagnet, an indicator package and a flat coil in the interpolar space, elastically attached to the ends of the electromagnet, while its axis passes through the center of the electromagnet in the plane of its neutral section, and the indicator package contains a magnetic fluid with a viscosity of 50 - 100 cSt and elastically suspended from the bottom plane of the coil. There is an inspection window in the upper part of the electromagnet. The disadvantages of this method and the device for its implementation are the low sensitivity and performance of control, as well as the impossibility of long-term storage of the obtained information about detected defects. Low sensitivity is caused, on the one hand, by the high viscosity of the indicator fluid (more than 50 cSt, while GOST R 56512-2015, clause 7.7. indicates that the viscosity of the magnetic fluid at the control temperature should not exceed 36 cSt, because the higher viscosity, the lower the sensitivity of the control. For this reason, a kerosene-oil-based magnetic suspension, as it is more viscous, has less sensitivity than a water-based suspension. In addition, during magnetization, the content of the magnetic powder in the central part of the control zone becomes depleted (concentration decreases) (which leads to a decrease in contrast and sensitivity of control) and at the same time an increase in the concentration of powder at the edges of the indicator package near the poles of the electromagnet [see G.S. Shelikhov. Magnetic particle flaw detection of parts and assemblies. Moscow, 1995, p. 64, Fig. 2.22] , especially when testing not flat, but cylindrical products, because when testing cylindrical products, especially when testing the vertical part of the surface, in addition to the magnetic forces acting on the powder, attracting it to the poles of the electromagnet, there are also gravitational forces that also cause displacement powder from the center of the indicator package to its lower edge. As a result, the concentration of the magnetic suspension in the central control zone becomes depleted and, accordingly, the sensitivity of the control decreases. That is why, in RF patent No. 2171984, before each magnetization, it is necessary to perform the operation of erasing the image in the indicator package and periodically mixing the magnetic fluid in it by shaking the package until a homogeneous environment is obtained, and all this reduces the control performance.

The disadvantage of all the above-mentioned methods and devices for magnetic particle flaw detection is also the lack of quantitative assessment (measurement) of the length and width of the magnetic powder indicator roller formed above the defect, because control and assessment of the size of defects is carried out only visually using the resulting defectogram.

At the same time, it is known [Pashagin A.I., Benklevskaya N.P. Magnetic-Powder Testing of Components Using Magnetic Indicator Packages, Russian Journal of Nondestructive Testing. Vol. 36.No. 9. 2000. pp. 640-646], that the main standard parameter when assessing the shape (point or extended defect) and the admissibility of the size of defects during magnetic particle testing is the extent (length) of the indicator roller, and the width of the roller can be used to assess the depth of detected defects. Therefore, measuring the length and width of the roller of magnetic powder deposited over a defect is an important and necessary indicator when assessing the size and acceptability of defects.

It is known to measure the length and width (opening) of a defect in the form of a crack in a weld during automatic visual inspection [S K Ho, R M White, J Lucas, A Vision Systems for Automated Crack Detection in Welds, Meas. Sci. Technol., 1990, vol. 1, no. 3, pp. 287-294]. The vision system used in this case, consisting of a CCD camera and a photo frame, is close to that presented in the above-mentioned Chinese patent CN 206920387. However, in the flaw detector according to patent No. 206920387 there is no instrumental measurement of the dimensions (length and width) of the indicator trace of the identified defect.

The radiographic inspection method also uses a method and device for measuring the length and width of a defect image obtained on an x-ray [Advertising brochure “Automatic system for improving and decoding images SOVA+, Testron, Moscow.”]. To do this, two electronic marks (markers) are placed on the boundaries of the area of maximum length (or width) of the defect and then the recorded segment of the length (or width) of the defect is compared with a reference segment of known length. As a result of the operation of the computing device, the length (width) of the defect shown in the image is obtained.

In the practice of manual magnetic particle testing, the use of electronic computational methods for flaw detection of identified defects, in particular, measuring the length and width of a magnetic powder roller on an indicator image of a defect, is not known in the literature, although the use of a system for measuring the length and width of an indicator roller will allow one to quickly obtain a quantitative assessment of identified defects , thereby increasing the accuracy and reliability of control, especially when assessing maximum permissible defects.

The proposed invention is based on the tasks of increasing the sensitivity, productivity and reliability of control, long-term storage of the information received about detected defects, and quantitative assessment of their sizes (length and depth).

The objectives are achieved due to the technical result that can be obtained by implementing the invention, namely: - Increasing the sensitivity and performance of control through the use of a special design of a reusable indicator package filled with a magnetic liquid with high control sensitivity (for example, a magnetic suspension in water or kerosene-oil base or fluorescent magnetic powder suspension) and the location of both sides of the indicator package (the bottom, adjacent to the product, and the outside, from which the image of the controlled area of the product is observed) parallel to the surface of the controlled product, ensuring a constant thickness of the suspension layer in the indicator package and, accordingly, uniform the concentration of the magnetic suspension on the entire surface of the controlled area of the product and, therefore, the same sensitivity of control in all places in this area.

Reliability of control, quantitative assessment of the size of detected defects and long-term storage of the obtained information is achieved through the use of a control unit containing a microprocessor to control the operation of the device, a video camera for photographic recording of the indicator trace of a defect, a display, a keyboard, and an electronic computing measuring device for measuring parameters (length and width) indicator trace is defective. The control unit performs the following functions:

- photographic recording of the resulting indicator images,

- processing the received images (enlargement or reduction) and calculating the size of the detected indicator traces (length and width) using an electronic computing measuring device,

- long-term storage of the received information in the data storage unit of the electronic computing device.

- measuring the dimensions (length and width) of indicator marks, which solves the issue of flaw detection of detected defects.

As a result, documentation and objective assessment of detected defects are carried out.

The essence of the invention is illustrated in Fig. 1-fig. 4.

In fig. 1 shows the inventive device for implementing the inventive method of magnetic particle testing of flat products or products with a small curvature of the inspected surface, with a wavy or rough roughness of this surface.

The device contains an electromagnet with a power source and sources of visible and ultraviolet light, an indicator package with a magnetic suspension, a control unit with a video camera and a duplicate remote control unit.

In fig. 2 - shows the control of products with a cylindrical surface (for example, pipes), when the magnetizing device is located on top of the product (horizontally).

In fig. 3 - the same as in Fig. 2, but the magnetizing device when inspecting cylindrical products is located on the side of the product (vertically).

In fig. 4 - design of an elastically deformable frame supporting the indicator package in the elastically deformable clamps of the electromagnet on the side of the controlled product.

The inventive device (Fig. 1) directly contains the magnetizing device itself - an electromagnet 2 with magnetizing windings; separate power supply 3; connector 4 for connecting power supply 3 to magnetizing device 2; button 5 to turn on/off the power supply to electromagnet 2; indicator package 9; elastically deformable frame 11; elastically deformable clamps-shock absorbers 12; sources of ultraviolet 13 and daylight 14 light, video camera 15; control unit 16 with display 17; remote control unit 7 connected to control unit 16 via connector 6; and when inspecting cylindrical products (Fig. 2 and Fig. 3), wedges 18 are mounted on the ends of the electromagnet 2.

The reusable indicator package 9 is filled hermetically with a magnetic suspension. The upper side 8 of the package 9 is made of elastic-deformable flat material (for example, plexiglass), transparent to visible and ultraviolet light, with a thickness of no more than 1 mm, and the bottom side 10 of the indicator package 9, in contact with the controlled product 1, is made of thin (10-50 µm), an easily deformable elastic non-magnetic film. A film 10 is used, for example, made of polyethylene or lavsan, transparent when inspecting products with a light surface or white when inspecting parts with a dark surface, to increase the contrast of the image of the indicator trace of a defect. It should be noted that lavsan film is preferable, because is an order of magnitude stronger than polyethylene, which ensures a longer, repeated service life of the indicator package 9. The lower side 10 of the indicator package 9 under the pressure of the suspension, due to its elasticity and small thickness, takes the shape of the surface of the product 1 (Fig. 1-3).

An elastically deformable frame 11 (Fig. 4) with a flanged inner edge placed under the indicator package 9 and supporting it from below serves to protect the package 9 from damage when installing and fastening it into elastically deformable clamps-shock absorbers 12 located at the ends of the poles of the electromagnet 2 .

On the inside of the electromagnet 2 there are sources of ultraviolet 13 and daylight 14 light with buttons for turning them on and off (not shown in the drawing) to illuminate the controlled surface of the product 1 in low light conditions. In the center of the inner side of the electromagnet 2 there is a video camera 15 of the control unit 16, located on top of the outer side of the electromagnet 2. All operation of the control unit 16 is ensured by the microprocessor located in it. On the display 17 of the control unit 16, an enlarged image of the controlled area of the product 1 is observed and registration is carried out (photo recording in the data storage device of the electronic computing measuring device) of those areas of the product in which defects are detected. The microprocessor of the control unit 16 also ensures the operation of an electronic computing measuring device built into the control unit 16 for measuring the length and width of the magnetic powder roller in the registered indicator trace of the detected defect observed on the inner side of the surface 10 of the indicator package 9.

When monitoring in difficult conditions (for example, in cramped, hard-to-reach, underwater, etc.) via connector 6, an external control unit 7 is connected to the control unit 16, which duplicates the operation of the control unit 16.

When testing cylindrical products, wedges 18 are used, which reduce the dissipation of the magnetic flux of magnetization at the point of contact of the electromagnet 2 with product 1, thereby ensuring higher sensitivity and stability of control.

The operating principle of the proposed device is as follows:

1. The power supply 3 is connected to the magnetizing device 2 via connector 4. It provides power to all devices located on the electromagnet 2;

2. An elastically deformable frame 11 is placed under the indicator package 9 from below and the indicator package 9 with the frame 11 is installed in the shock-absorber clamps 12;

3. Using button 5 in the magnetization mode of product 1, turn on/off the power to the electromagnet 2 itself;

4. Sources of ultraviolet 13 and daylight 14 light with buttons for turning them on and off (not shown in the drawing) are used to illuminate the controlled surface of the product 1 in low light conditions;

5. Video camera 15 of the control unit 16 is used to monitor the controlled area of the surface of the product 1;

6. All operation of the control unit 16 is provided by the microprocessor located in it. On the display 17 of the control unit 16, an enlarged image of the controlled area of the product 1 is observed and registration is carried out (photo recording in the data storage device of the electronic computing measuring device) of those areas where defects are detected;

7. Remote control unit 7 duplicates the operation of control unit 16 (if necessary).

The inventive control method is carried out using a device (Fig. 1-3) as follows:

1. The magnetizing device with the indicator package 9 and frame 11 fixed in the shock-absorber clamps 12 is installed on the controlled surface of the product 1;

2. Using button 5, turn on the power to the coils of electromagnet 2 and magnetize the controlled part 1 with an alternating magnetic field;

3. Determine visually using a video camera 15 the presence or absence of a defect in the controlled area of the product 1 on the display 17 of the control unit 16 by the appearance or absence of a pattern formed by particles of magnetic powder in the package 9 under the influence of the magnetic stray field from the defect;

4. If there is no defect (there is no picture of the defect), turn off the power to the magnetizing device with button 5 and move the device to a new testing area;

5. If a trace of a defect formed in the indicator package 9 is detected, an enlarged image of this trace is examined on the display 17 of the control unit 16, and then it is registered - this image is recorded (photographed) using a video camera 15 in the data storage device of the electronic computing measuring device block 16;

6. After this, turn off the power to the magnetizing device with button 5;

7. Next, on the image of the indicator trace of the detected defect presented on the display 17, also using the microprocessor of block 16, the length and width of the magnetic powder roller above the defect are measured in order to estimate the size of the detected defect;

8. Continue monitoring as described above, sequentially moving the magnetizing device to new areas of the product and alternately magnetizing these areas.

It should be noted that when the power is turned off and the electromagnet 2 is separated from the controlled area and moved to a new area, the magnetic suspension, under the influence of gravity and due to the elasticity of the surface 10 of the indicator package, tends to the center of the package. As a result, when installing the package on a new controlled area of the product, the magnetic suspension is automatically mixed and the concentration of magnetic powder in it is equalized, thereby ensuring the same sensitivity of control in all controlled areas of the product 1.

When inspecting products with a cylindrical surface (Fig. 2 and Fig. 3), wedges 18 are mounted on the ends of the electromagnet 2, which can be replaceable and have a different bevel angle depending on the diameter of the product 1.

Analysis of the claimed method and device for its implementation with the closest methods and devices showed that the claimed method differs from the known ones described above by new additional operations:

- the use of an indicator package 9 with a highly sensitive magnetic suspension, which, in combination with an elastic-deformable frame 11 placed under the package 9 on the side of the product 1, which protects the thin elastic side 10 of the package 9 from tears when installed in elastic-deformable clamps 12, provides the same sensitivity control in all controlled areas of flat or cylindrical products and high testing performance;

- optical observation with increased resolution on the display 17 of the control unit 16 of images of controlled areas of the surface of the product 1 and documentary registration of images of those areas where defects are detected;

- quantitative measurement of the length and width of the magnetic powder bead in the indicator trace of a detected defect in order to estimate the size of this defect.

And the claimed device is distinguished by new features:

using a special design of a reusable indicator bag filled with a hermetically sealed magnetic suspension, the upper side of which is made of a flat, elastically deformable transparent material that transmits visible and ultraviolet light, and the side in contact with the controlled product 1 is made of thin (10-50 microns), an easily deformable elastic non-magnetic film that takes the shape of the surface of the product. The design ensures parallelism of both sides 8 and 10 of the indicator package 9 both when inspecting flat and cylindrical products, which makes it possible to have the same thickness of the layer of magnetic suspension in the package 9 on any part of the surface of the product 1, respectively, a more uniform concentration of magnetic powder in the suspension and, as a consequence, the same sensitivity of testing on any part of the surface of the controlled product, which is unknown in the literature;

- repeated use of the same indicator package for monitoring in the visible or ultraviolet light spectrum with constant sensitivity of both flat and cylindrical products significantly increases the reliability and performance of monitoring and reduces its cost, unknown in the literature;

- the use of a thin (about 0.1-0.5 mm, depending on the material used) flat elastic-deformable frame 11 supporting the indicator package on the product side, made of a springy solid material (for example, non-magnetic steel, bronze, duralumin, plexiglass and etc.) with a smoothly flanged inner edge, reduces the likelihood of damage to the lower thin side 10 of the indicator package 9 when installing and securing it in the elastic shock-absorber clamps 12 and thereby ensures, if necessary, its prompt replacement and reliable operation, also in unknown in the literature;

- the use of a recording device containing a lens (video camera), a digital microprocessor and a display, widely used in various models of modern smartphones, etc. However, the use of such devices in a single design with a magnetizing device for monitoring, during manual control, enlarged images of controlled areas of the product and for recording detected defects, in particular, in the control unit 16 of the electronic measuring device for determining the length and width of the magnetic powder roller in indicator trace of a detected defect, forms, according to the inventive concept, a single functionally related inspection process and is unknown in the literature.

Thus, an analysis of the level of technology for compliance of the claimed technical solutions with the patentability condition of the invention “inventive step” showed that the claimed method of magnetic particle testing and the device for its implementation meet the criterion of the invention “novelty”.

Information sources:

1. N.I. Eremin, “Magnetic particle flaw detection”, 1947, ed. Ministry of Heavy Engineering of the USSR, 1947, 152 p. see Ch. III-IV.

2. G.S. Shelikhov. Magnetic particle flaw detection of parts and assemblies. Moscow, 1995

3. Copyright certificate of the USSR No. 557305, G01N 27/84 dated 06/18/77.

4. PRC patent CN 206920387 U, Int.Cl. GO IN 27/84, dated 2018.01.23.

5. K.G. Walther. "The Magfoil Method", Material Evalution, 1983, vol. 41, no. 5, p. 582-585.

6. RF Patent No. 2171984, IPC G01N 27/84 dated 12/15/1998.

7. Pashagin A.I., Benklevskaya N.P. Magnetic-Powder Testing of Components Using Magnetic Indicator Packages, Russian Journal of Nondestructive Testing. Vol. 36.No. 9. 2000. pp. 640-646.

8. S K Ho, R M White, J Lucas, A Vision Systems for Automated Crack Detection in Welds, Meas. Sci. Technol., 1990, vol. 1, no. 3, pp. 287-294.

9. Prospect Automatic system for improving and decoding images SOVA+, Testron company, Moscow.

Claims (5)

1. A method of magnetic particle flaw detection, which includes installing an electromagnet on the surface of the test product with an indicator package fixed in its elastically deformable spring clamps, made of non-magnetic material and filled with a magnetic suspension; exposure to an alternating magnetic field of an electromagnet on a controlled product; detection of an indicator trace of a defect in the form of a roll of magnetic powder in the indicator package as a result of the interaction of the magnetic field with the material of the product in the image control zone; visual observation of this trace on a recording device with increased resolution and its recording in the memory of the microprocessor of the recording device, characterized in that the indicator package with an elastic-deformable frame supporting it from below is installed with the lower thin elastic side on the controlled section of the surface of the product, and the outer flat elastic-deformable side of the package and the underlying From below, under the bag, the frame is springily installed parallel to the surface of the product being inspected, ensuring the same thickness of the suspension layer in the bag throughout the entire inspected area of the product. 2. The method according to claim 1, characterized in that the length and width of the roller of the indicator trace of the identified defect are measured using an electronic computing measuring device on the resulting indicator image. 3. A device for implementing the inventive method of magnetic particle flaw detection according to claim 1, consisting of a power supply; an electromagnet with magnetization coils and visible and ultraviolet light sources and a video camera installed on its upper inner side, and on the outer side of the electromagnet installed on/off buttons for the power of the electromagnet and visible and ultraviolet light sources; a control unit containing a digital processor that ensures registration of the resulting indicator images of a defect and measurement of their length and width, a display, and a control keyboard; connector for connecting a backup remote control unit for monitoring in hard-to-reach places; an indicator package filled with magnetic fluid and installed in the interpolar space of the electromagnet in elastically deformable spring clamps fixed on the inner side of the poles of the electromagnet, which spring the package to fit it on the controlled surface of the product, characterized in that the indicator package is made from the side adjacent directly to the controlled surface of the product , from a thin, easily deformable, elastic, non-magnetic, transparent film for inspection of products with a light surface and white film for inspection of products with a dark surface, and the opposite outer side of the bag is made of a flat, elastically deformable, transparent material that transmits visible and ultraviolet light, for example, plexiglass . 4. The device according to claim 3, characterized in that an electronic computing measuring device is used in the control unit to measure the length and width of the magnetic powder roller of the defect indicator trace. 5. The device according to claim 3, characterized in that under the indicator package on the side in contact with the product, for prompt, damage-free installation of the package into elastically deformable clamps, a flat elastically deformable frame with a flanged inner edge and rounded inner corners is placed on the inner side the frames along its perimeter apply a scale scale for a preliminary, before using an electronic computing device, operational, visual assessment of the dimensions of the indicator roller and, accordingly, the defect itself on the product.

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