Method of low-frequency ultrasonic liquid-penetrant inspection

Abstract

FIELD: low-frequency ultrasonic liquid-penetrant inspection.SUBSTANCE: surface of the product to be tested is cleaned, treated with a cleaner, impregnated with an indicator penetrant; excess penetrant is removed from the surface of the test by wiping or rinsing with the cleaner; the developer is applied and the indications are recorded, while at the stage of impregnation of the test surface area with a weld seam with an indicator penetrant, a capillary-porous pad with a penetrant solution is placed on it and, in resonance mode, normally to the surface, ultrasonic impregnation of the penetrant introduced into the weld seam in the test area is carried out by intermittent contact sounding with a waveguide - emitting disk, then, at the stage of development of possible defects of the capillary level, carried out after removal of the penetrant from the test surface and application of the developer, the initiation of a reverse acoustocapillary effect is carried out in resonance mode and normally to the surface, realizing the extraction of the contents of the capillary level defect by ultrasonic drainage, carried out by a waveguide - emitting disk.EFFECT: increasing the reliability of product control for the presence of capillary level defects.3 cl, 17 dwg

Description

[0001] The invention relates to non-destructive testing methods—capillary flaw detection methods—conducted during leak testing of products [1], where increased demands are placed on the reliability of diagnostics for the presence of permeable capillary-level defects in products manufactured using various types of connections, including welding, that affect the tightness of the walls, for example, in closed, liquid-filled products of critical applications of both small and large capacity. Moreover, the test objects can be made of electrically and non-conductive, magnetic and non-magnetic materials, polymers, ceramics, etc., used in mechanical engineering and other industries.

[0002] A method for testing tightness is known [2], which consists in filling the product with a water-based test liquid containing a surfactant mixed with a water-soluble solvent - acetone, creating excess pressure and, when the test liquid penetrates through the defective wall of the product, judging its tightness.

[0003] However, the preparation of the test liquid in a mixture with a water-soluble solvent - acetone, reduces the technological effectiveness of the leak test method, which requires a lot of time and measures to prevent fire hazard, especially under the conditions of using the method for leak testing of large-capacity products with welded seams of great length and complex configuration.

[0004] A known method of capillary flaw detection [3] consists in the fact that a cleaner containing gum turpentine and isopropyl alcohol is applied to the area of ​​the test surface, which is used to clean the test surface; a penetrant is applied: a mixture of butyl alcohol, rhodamine 6G, and the phosphor Shirvanol-2; excess penetrant is removed; the test surface is wiped with a cleaner; a developer is applied: P-1 or P-4; the test surface is examined in visible or ultraviolet light.

[0005] However, this method of capillary flaw detection has limitations in the manufacture of large-sized products using welded seams of various configurations and great length, where dead-end and through defects of the capillary level cannot be ruled out, affecting the tightness of the tested objects: fatigue cracks and capillary channels, pores, lack of fusion, cracks in welded seams, etc., including those that may include liquid "plugs" (potentially - leaks), as well as partially unremoved penetrant, held by capillary forces, when the depth of the defect is 5-10 times or more, exceeding its cross-section [4]. At the same time, incompletely removed residues of the indicator liquid - penetrant, often initiate "false" indications. In addition, the method has limitations when testing the tightness of large-sized products in the form of closed containers, where through defects in the capillary level with liquid “plugs” cannot be ruled out.

[0006] A method of capillary flaw detection is known [5], which consists in the fact that a penetrating indicator liquid - penetrant - is applied to the area of ​​the product's test surface, the product is grounded, and a high-voltage electrode is placed above it, externally acting with a constant electric field, normal to the product's test surface, which increases the rate of penetration of the penetrant into the defect model - a crack, but the process of its extraction from the crack was not considered.

[0007] However, this method of capillary flaw detection is difficult to implement when testing the tightness of large-sized products, due to the insufficient technological effectiveness of the proposed flaw detection process, which requires a lot of time when testing welded seams of great length and complex configuration.

[0008] The closest technical solution to the proposed one is a non-destructive testing method using physical factors: ultrasonic vibrations and a constant non-uniform magnetic field, related to capillary flaw detection [6], consisting of cleaning the surface of the product to be tested from contaminants; immersing it in an indicator solution mixed with a ferrophase (penetrant + ferrophase), exposure to a magnetic field, the gradient of which is directed along the internal normal to the surface of the test, in the direction of which low-frequency ultrasonic vibrations are also excited in the indicator solution, which, along with the magnetic field, accelerates the impregnation of defect zones. Upon completion of the impregnation stage of the surface of the test, the indicator solution is removed and a developer is applied to it, and then the product is placed in a magnetic field, the gradient of which is directed along the external normal to the surface of the test, allowing the extraction of the indicator solution "penetrant + ferrophase" from the cavities of the defects.

[0009] However, this penetrant flaw detection method, designed for testing small components, is not applicable for non-destructive leak testing of large-sized closed containers manufactured using welding technologies and containing multiple welded seams of varying configurations and lengths. These contain potential for capillary-level microdefects, including liquid "plugs," which can affect leak testing. Furthermore, complete removal of the penetrant+ferrophase mixture from defect cavities is not guaranteed, which may result in false indications.

[0010] At the same time, industry is in demand for simple and reliable diagnostic methods based on capillary flaw detection, enabling the inspection of large, critical components with small or large closed containers filled with liquid or gas-liquid media during operation, operating under high dynamic loads and temperature fluctuations. The manufacture of such components involves a large number of technological operations involving welded joints of varying configurations and lengths, which can include both surface-mounted and through-hole capillary defects that affect the tightness of the component walls. These defects often contain "plugs" of liquid retained by capillary forces, preventing their removal, thereby masking any defects that may have arisen during manufacturing.

[0011] Detecting and eliminating liquid "plugs" is a problem that requires a solution. When hydraulically testing these and similar products for leaks, increased demands are placed on reliability and safety, as well as technical and economic feasibility. These requirements reduce the duration of product inspections and improve the reliability of testing for capillary-level defects, including liquid "plugs" and other defect cavity contents (traces of crack formation products, flaw detection materials, etc.).

[0012] The technical result of the invention is to increase the technological efficiency and reliability of product testing for the presence of capillary-level defects, including those with liquid "plugs", which is ensured by intensifying the mass exchange of the contents, allowing for faster and better visualization of defect indications (defects) in testing areas implemented by remote low-frequency ultrasonic capillary flaw detection.

[0013] The technical result of the invention is achieved by the fact that, according to the method of remote low-frequency ultrasonic capillary flaw detection, carried out during the inspection of a product for the presence of capillary level defects containing liquid "plugs", including the steps of: cleaning the inspection surface of the product, treating it with a cleaner, impregnating it with an indicator penetrant; removing excess penetrant from the inspection surface by wiping or rinsing with a cleaner;application of a developer and recording of indications, characterized in that at the stage of impregnation of the test surface area with a weld with an indicator penetrant, a capillary-porous pad with a penetrant solution is placed on it and, in the resonance mode, normal to the surface, ultrasonic impregnation of the penetrant introduced into the weld in the test area is carried out by intermittent contact insonification with a waveguide - a "radiating disk", the front radiating end of the working part of which, in the form of a paraboloid of revolution, is made without draining nozzle channels. Parameters of insonification with high-intensity ultrasound, at the stage of ultrasonic impregnation of penetrant: ultrasound frequency f = 26.5 kHz, sound pressure p; рез. - about 130 dB, sounding time τ - about 3 sec / cm 2weld. Then, at the stage of revealing possible capillary-level defects, carried out after removing the penetrant from the surface and applying the developer, a "reverse" sound-capillary effect is initiated in resonance mode, normal to the surface, realizing the extraction of the contents of the capillary-level defect by ultrasonic drainage, carried out by a waveguide - a "radiating disk", the front radiating end of the working part of which, in the form of a paraboloid of revolution, is made with drainage nozzle channels. Parameters of high-intensity ultrasound, at the stage of revealing possible capillary-level defects: ultrasound frequency f = 26.5 kHz; sound pressure p рез.- approximately 150 dB; the resonant distance between the front emitting end of the waveguide (the "emitting disk") and the weld section on the test surface is within 1 / 8 to 1 / 32 of the wavelength λ, ultrasound, or acoustic boundary layer, excluding contact between the front emitting end and the weld on the test surface. In this case, the initiation of the "reverse" acoustic-capillary effect during remote insonification of the target area of ​​the weld trajectory continues until a time sufficient to fully record the resulting indication, indicating the presence of a capillary level defect in the weld.

[0014] In addition, a capillary-porous pad made of sorbent non-woven fibrous material is used as a sorbent element, on the one hand, performing the function of a penetrant depot during its ultrasonic impregnation in the area of ​​the weld seam in the control area, and on the other hand, the function of a sorbent for the products of extraction of contents from a capillary level defect, realized by ultrasonic drainage initiated by the “reverse” sound-capillary effect

[0015] The conducted patent search showed that, as of the filing date of the invention application, there is no known method for remote low-frequency ultrasonic capillary flaw detection that increases the capabilities of ultrasonic capillary flaw detection technologies by controlling the processes of mass transfer of contents in the weld of the product's inspection area ("plugs" of liquid, traces of flaw detection materials, etc.), implemented by contactless extraction from cavities of capillary-level defects by ultrasonic drainage initiated by the "reverse" sound-capillary effect (hereinafter - OUzCE).

[0016] The essence of the invention is explained graphically and by photograms:

[0017] - Fig. 1 - images of known and also used stages of capillary flaw detection and variants of their implementation, used in the proposed method of remote low-frequency ultrasonic capillary flaw detection;

[0018] - in Fig. 2 - Fig. 6 - schematic representation of the general appearance and arrangement of the main technical elements and devices implementing the proposed method of capillary ultrasonic flaw detection in checking for leaks and the presence of capillary level defects: 1 - tested product; 2 - weld seam (longitudinal or annular); 2.1 - capillary level defect with a liquid "plug"; 3 - USG (ultrasonic device "Extracton-2MM", f = 26.5 kHz); 4 - acoustic unit; 5 - waveguide - "radiating disk" group 5 (n = 2; ∅ изл. =16 mm) without drainage holes in the form of nozzle channels; 6 - waveguide-“radiating disk” group 6 (n=2; ∅ изл. =16 mm) with drainage nozzle channels, for example, conical ones - 6.2, equipped with a sorbing element 6.3;

[0019] - Fig. 7 - schematic representation of a trace of defect 2.1 in the weld zone 2 after remote extraction of penetrant solution 8, initiated by OUzKE;

[0020] - in Fig. 8a, b - sets of waveguides - "radiating disk" of different diameters, having on their working part frontal, in the form of a paraboloid of revolution, radiating ends without drainage holes in the form of nozzle channels - group 5 (a) and having, for example, conical nozzle channels - group 6 (b);

[0021] - in Fig. 9a, b - the result of finite element modeling of oscillatory bending displacements of the annular region of the disk-shaped flexural-oscillating working part of the waveguide - "radiating disk", made without drainage holes in the form of nozzle channels (a) and having, for example, conical nozzle channels (b). Load - air;

[0022] - in Fig. 10 - a sample of the ultrasonic apparatus “Extracton-2MM” (f=26.5 kHz), implementing the proposed method of ultrasonic capillary flaw detection;

[0023] - in Fig. 11a, b - photograms of distant extraction of a model liquid, initiated by OUzKE, in the form of a dispersive aerosol, from a capillary-porous sample (h oбp=8 mm; branched pores-capillaries; ∅ пор =2-5 µm), in contact (at the base) with the liquid and implementing distant ultrasonic drainage of the liquid by waveguides - “radiating disk”, where on:

[0024] - Fig. 11a shows a waveguide-"radiating disk" 5 (group 5) with a disk-shaped working part having a front radiating end (∅12-40 mm and more), in the form of a paraboloid of revolution without draining nozzle channels. Parameters at resonance: ultrasound frequency f = 26.5 kHz; sound pressure p рез. - about 130 dB; L рез.- 1 / 8…1 / 32 of wavelength λ (f=26.5 kHz). Waveguide-"radiating disk" 5 (group 5) implements, remotely, with high kinetic energy, extraction and irradiation, into the external environment, of an aerosol flow torch. Waveguides-"radiating disk" 5 (group 5) are used mainly for ultrasonic impregnation in the area of ​​​​weld seam 2 of penetrant 8 through a capillary-porous gasket 7 saturated with it. Their use in the extraction of penetrant 8 is impractical, since sealants of the extraction zone are necessary, which limits their application in relation to the working area and the environment;

[0025] - Fig. 11b shows a waveguide-“radiating disk” 6 (group 6) with a disk-shaped working part having a frontal radiating end (∅12-40 mm and more), in the form of a paraboloid of revolution with draining nozzle channels 6.2, allowing remotely, at resonance and with the following mode parameters: ultrasound frequency f=26.5 kHz; sound pressure p рез. - about 150 dB; L рез.- 1 / 8…1 / 32 of the wavelength λ (f=26.5 kHz), with high kinetic energy, extract, forming a directed torch of penetrant flow 8 to the developer 9, and outside of it, ensure deactivation of the “traces” of aerosol by using a sorption capillary-porous element 6.3, blocking the drainage nozzle channels from the rear end of the waveguide - “radiating disk” 6 (Fig. 6, pos. 3);

[0026] - in Fig. 12 - experimental setup I for estimating the rate of distant ultrasonic drainage (extraction) of penetrant 8 from capillary-porous system sample 11 (hereinafter referred to as CPS sample 11) onto its surface (S), initiated by OUzCE, as well as the dynamics of its interaction with developer-reagent 9 until the moment of complete fixation of the formed indication of penetrant 8 on the surface of CPS sample 11, where: 3 - ultrasonic device "Extract-ton-2MM" (f=26.5 kHz); 4 - acoustic unit; 5 - waveguide-"radiating disk" (group 5) (n=2; ∅=16 mm) or 6 - waveguide-"radiating disk" (group 6) (n=2; ∅=16 mm); 12 - stand for vertical movement of the acoustic unit 4; 13 - second stand with a holder for Petri dish 14; 11 - sample of KPS (30×25×8 mm);

[0027] - in Fig. 13 a, b, c, d, e, f, g, h - evaluation of the development rate of the penetrant solution, remotely extracted by ultrasonic drainage, upon initiation of the OUzCE, from the CPS sample and entering into a physicochemical interaction with the developer-reagent applied to the surface of the CPS sample, where:

[0028] - Fig. 13a - the original image of the KPS 2 sample with randomly located microcapillaries (∅=2-5 µm), simulating branched microcracks;

[0029] - in Fig. 13b - the stage of ultrasonic impregnation of penetrant 8 into the KPS sample by intermittent contact sounding of the gasket 7 saturated with a solution of penetrant 8;

[0030] - in Fig. 13c - sample of KPS 2, saturated with penetrant solution 8;

[0031] - in Fig. 13 g - the stage of applying the developer-reagent 9 to the surface (S) of the KPS 2 sample using a spray gun;

[0032] - in Fig. 13d - the beginning of the stage of accelerated distant extraction of the penetrant solution 8 from the depth of the sample of the CPS 2 onto its surface, covered with the developer-reagent 9, realized at resonance, in the field of developed cavitation, facilitating the intensification of their physicochemical interaction (τ1 - about 2 seconds of sounding);

[0033] - in Fig. 13e - the development of the stage of accelerated distant extraction of the penetrant 8 solution from the KPS 2 sample onto its surface, covered with the developer-reagent 9, in the process of its interaction with the penetrant 8. A sharp increase in the area of ​​manifestation of indicator traces of penetrant 8 is observed (τ2 - about 6 seconds of sounding);

[0034] - in Fig. 13g - the development of the stage of accelerated distant extraction of the penetrant 8 solution from the KPS 2 sample onto its surface, covered with the consumable developer-reagent 9, in the process of its interaction with the penetrant 8. Continuation of a sharp increase in the area of ​​manifestation of indicator traces of penetrant 8 (τ3 - about 12 seconds of sounding);

[0035] - in Fig. 13z - completion of the stage of accelerated remote extraction of the penetrant 8 solution from the KPS 2 sample onto its surface covered with the consumable developer-reagent 9, in the process of its interaction with the penetrant 8, which is expressed in the development of the indicator penetrant 8 on the entire surface of the KPS 2 sample (τ4 - up to 15 seconds of sounding);

[0036] - in Fig. 14 - Estimation of the rate of distant drainage (extraction) of penetrant from sample KPS 2 due to the OUzCE initiated by the waveguide-“radiating disk” 6 group 6 (Fig. 1, stage V: variant 2). A practically direct dependence of the accelerated ultrasonic drainage (extraction) of penetrant 8 on the surface (S) of sample KPS 2, covered with consumable developer-reagent 9, depending on the time of its distant sonication was obtained;

[0037] - in Fig. 15 - experimental setup I for evaluating the dynamics of liquid extraction from a defect initiated by OUzKE (manifestation of defect indication patterns), where: 3 - ultrasonic apparatus "Ekstrakton-2MM" (f=26.5 kHz); 4 - acoustic unit; 5 - waveguide-"radiating disk" of group 5 (n=2; ∅=16 mm) or 6 - waveguide-"radiating disk" of group 6 (n=2; ∅=16 mm); 12 - rack for vertical movement of acoustic unit 4; 13 - the second rack with a holder for vertical movement and rotation of the system model (ZYoZh+PK+Zh); 15 - system model (ZYoZh+PK+Zh). Source of liquid supply and discharge - not shown;

[0038] - in Fig. 16a, b, c, d, e, f - a model of the system (ZhEZh+PK+Zh) 15 of the experimental setup I, which allows, upon initiation of the OUzKE, to estimate the speed of the process of opening, moving and extracting a “plug” of liquid (Zh) + penetrant solution 8 from the PC, which is remotely extracted by ultrasonic drainage, entering into a physicochemical interaction with the developer-reagent 9 applied to the surface of the region of the annular weld 15.3 of the model of the system (ZhEZh+PK+Zh) 15, where:

[0039] - in Fig. 16a - a model of the system (ZЁZh+PK+Zh) 15 in the form of a closed container having, in the junction zone of two metal pipes 15.1 and 15.2, a knowingly defective annular weld 15.3 with permeable capillaries (PK), including "plugs" of liquid (Zh), obtained when supplying and then removing liquid from the cavity of the model of the system (ZЁZh+PK+Zh) 15; 5 - a waveguide - "radiating disk" of group 5 (n=2; ∅16 mm); the system for supplying and removing liquid is not shown;

[0040] - in Fig. 16b - model system (ZЁZh+PK+Zh) 15, where after cleaning the zone adjacent to the annular weld seam 15.3 (Fig. 1, stage I, variants 1+2), a capillary-porous gasket 7 with a penetrant solution 8 is placed on the seam 15.3, and then intermittent-contact insonification is carried out with a waveguide-“radiating disk” 5 (group 5) (n=2; ∅16 mm) of the gasket 7, along the entire trajectory of the annular weld seam 15.3, ensuring the process of accelerated ultrasonic impregnation of the penetrant solution 8 into the weld seam along its entire trajectory (Fig. 1, stage II, variant 2). It is realized by the sound-capillary effect of UzKE [7];

[0041] - in Fig. 16c - intermediate cleaning of the area of ​​the annular weld seam 15.3, along its entire trajectory (Fig. 1, stages III and IV, options 1);

[0042] - in Fig. 16g - application of developer 9 to the area of ​​the annular weld seam 15.3, along its entire trajectory (Fig. 1, stage V, option 1; Fig. 5);

[0043] - in Fig. 16d - selection of resonant distance L рез.between the radiating end of the waveguide - “radiating disk” 6 (group 6) (n=2; ∅16 mm) and the weld seam 15.3;

[0044] - in Fig. 16e - the stage of defect indication during the physical-chemical interaction of the extracted penetrant 8 with the developer-reagent 9, by distant sounding of the weld seam 15.3, at a resonant distance L рез. between the radiating end of the waveguide - "radiating disk" 6 (group 6) (n=2; ∅16 mm) and the weld seam 15.3, along its entire trajectory (Fig. 1, stage V, option 2). It is realized by the "reverse" sound-capillary effect (RSCE) [8, 9];

[0045] - in Fig. 16g - an enlarged image of defect indications, the manifestation of which is shown in Fig. 16e;

[0046] - in Fig. 17 - evaluation of the rate of development of penetrant solution 8 with contents from a capillary level defect, when interacting with developer-reagent 9 in the area of ​​the annular weld seam 5.3 of the model system (ZYoZh+PK+Zh) 4, depending on the type of factor initiating extraction.

[0047] The proposed method of remote low-frequency ultrasonic capillary flaw detection (Fig. 1-Fig. 17) is carried out using a device that includes an ultrasonic apparatus “Extracton-2MM” 3 (Fig. 10) with an operating frequency f paб.=26.5 kHz and the piezoceramic acoustic unit 4 connected to it. At different stages of remote low-frequency ultrasonic capillary flaw detection, the following are connected to the acoustic unit 4: waveguides-“radiating disk” 5 (group 5) of different diameters, proportionate to the inspection zone of the product 1, having on their working part 5.1 frontal, in the form of a paraboloid of revolution, radiating ends without drainage nozzle channels, as well as waveguides-“radiating disk” 6 (group 6) of different diameters, having on their working part 6.1 frontal, in the form of a paraboloid of revolution, radiating ends, equipped with drainage, for example, conical nozzle channels 6.2 (Fig. 8a, b and Fig. 9a, b). Also, in the control zone of product 1 (Fig. 1-Fig. 4), a sorbent capillary-porous pad 7 with a solution of indicator penetrant 8 (penetrant 8) is used, the width of which exceeds the width of the weld seam 2.Before the stage of remote low-frequency ultrasonic extraction, a developer-reagent 9 is applied to the area of ​​interest for control of the weld seam 2 using a spray bottle 10 (Fig. 5).

[0048] The method of remote low-frequency ultrasonic capillary flaw detection is carried out as follows.

[0049] After determining the inspection area of ​​the product, the area of ​​the weld seam 2 is cleaned of contaminants (Fig. 1, stage I: option 1) - mechanical cleaning of the seam with a brush, then option 2 - cleaning the seam with a cleaner (Aeropen-KD LR-1, Cleaner Art. 9902.71. Along the trajectory of the interested section of the weld seam 2 (Fig. 1, stage II: option 2), a capillary-porous gasket 7 saturated with a solution of penetrant 8 (Aeropen-KD RF-1, Penetrant red Art. 9901.71) is placed. Then, remotely, normally to the surface of the capillary-porous gasket 7 in contact with the weld seam 2, an acoustic unit 4 is installed, connected to a waveguide - "radiating disk" 5 (group 5) without drainage nozzle channels on working part 5.1. The diametrical size of the working part of the waveguide - "radiating disk" 5, is basically commensurate with the width of the capillary-porous gasket 7.

[0050] By turning on the ultrasonic device “Extracton-2MM” 3, in the resonance mode, with the above parameters of high-intensity ultrasonic exposure, ultrasonic impregnation is carried out by intermittent contact sounding with a small periodic pressure on the capillary-porous gasket 7 with penetrant 8 introduced along the trajectory of the weld seam 2 in the control area (Fig. 1-Fig. 4, stage II: option 2). This ensures accelerated filling of defect 2.1 in weld seam 2 with penetrant 8, due to developed cavitation and the initiated sound-capillary effect (USCE) [7], where hydrodynamic processes in the ultrasound field are realized by a special type of unidirectional flows in the direction of its propagation, characterized by high speed and depth of penetration of liquid into capillaries, cracks and discontinuities, compared to the action of radiation forces.Then, the ultrasound is switched off, the capillary-porous gasket 7 with the remains of the penetrant 8 is removed from the surface of the test area and the following is performed: intermediate cleaning of the weld area with a sponge soaked in a cleaner (Fig. 1, stage III: option 1) - Aeropen-KD LR-1, Cleaner Art. 9902.71 and, then, the weld area 2 is dried by wiping with a lint-free cloth (Fig. 1, stage IV: option 1). Then, the developer 9 is sprayed onto the weld area 2 using a spray bottle 10 (Fig. 1, stage V: option 1) - Aeropen-KD NWE-1, Developer Art. 9903.71. After its application, in resonance mode, the normal surface of the control area initiates a “reverse” sound-capillary effect (RSCE) [8-10, etc.], where, along with the manifestation of the known sound-capillary effect (SCE) [7], which consists in an anomalous increase in the height of the rise of liquid media in the capillary in the direction of ultrasound propagation, a similar effect is manifested, an anomalous increase in the height and speed of the rise of the liquid in the capillary, but in the direction opposite to the propagation of ultrasound (Fig. 11a and Fig. 11b), initiated distantly [8-10, etc.]. This ensures contactless extraction of the contents of capillary-level defects by ultrasonic drainage along the trajectory of the weld 2, carried out by the disk-shaped working part 6.1 of the waveguide - "radiating disk" 6 (group 6), the front radiating end of which is made in the form of a paraboloid of revolution with draining nozzle channels 6.2. The impact is carried out under the parameters of the developed cavitation mode: ultrasound frequency f=26.5 kHz; sound pressure p. рез. - about 150 dB; resonant distance L рез.within 1 / 8…1 / 32 of the wavelength λ of ultrasound or the acoustic boundary layer between the front emitting end of the waveguide-“emitting disk” 6 (group 6) and the weld 2 on the testing surface, excluding contact of the emitting end with the weld 2. Initiation of the OUzKE, with distant insonification of the interested area of ​​the trajectory of the weld 2, is carried out until a time sufficient for the formation of a steady-state indication pattern, due to the physicochemical interaction of the penetrant solution 8 with the developer-reagent 9, activated in the field of distant high-intensity ultrasound, indicating a capillary level defect in the weld 2 (Fig. 6 and Fig. 7). Documentation of the indication - according to stage VI: options 1 and 2 (Fig. 1).

[0051] In support of the proposed method of remote low-frequency ultrasonic capillary flaw detection, we present some results of physical modeling of the process of remote exposure to low-frequency ultrasound on capillary-porous systems in contact with a liquid medium, allowing us to consider it as a possibly promising capillary method of non-destructive testing of materials and products, based on the possibility of controlling, in a field of high-intensity ultrasound, the mass exchange of indicator liquids in the cavities of surface or through discontinuities of the material of the objects of testing.

[0052] Fig. 11a, b show photograms of the distant extraction of a model liquid in the form of a dispersed aerosol obtained by ultrasonic drainage of liquid from a capillary-porous system in contact, at the base, with a liquid medium, due to the initiation of the “reverse” sound-capillary effect by waveguides - “radiating disk”, where:

[0053] - Fig. 11a shows a waveguide-"radiating disk" 5 (group 5) with a working part - a front radiating end in the form of a paraboloid of revolution without drainage channels. At resonance, with the following operating parameters: frequency f = 26.5 kHz, sound pressure p рез. =150 dB, resonant range L рез - within 1 / 8…1 / 32 of the ultrasound wavelength λ (f=26.5 kHz). The waveguide-"radiating disk" 5 (group 5) remotely, with high kinetic energy, extracts and irradiates into the external environment an aerosol plume of the solution (Newtonian fluid), which limits the use of the waveguide-"radiating disk" 5 (group 5) due to the irradiation of the solution aerosol, for example, penetrant, etc., into the environment, which is unacceptable and will require the presence of special sealants and aerosol deactivators;

[0054] Fig. 11b shows a waveguide-"radiating disk" 6 (group 6) with a working part - a frontal radiating end in the form of a paraboloid of revolution, but with draining nozzle channels. It, at the above-mentioned parameters of the resonant mode of distant insonification, forms a directed movement of the aerosol torch flow of a Newtonian fluid solution, for example, a solution of penetrant 8, etc., which allows the capture of "trace" quantities of it by the sorbing element 6.3, installed on the rear end of the multi-zone waveguides-"radiating disk" 6 (group 6), absorbing and deactivating "trace" quantities of aerosol (Fig. 6).

[0055] Patent and bibliographic search showed the absence of data on the use of the "reverse" sound-capillary effect - OUzCE for remote "opening" of a capillary level defect, including in the presence of a liquid "plug" in a permeable capillary (PC), by moving and extracting liquid (L) by ultrasonic drainage from the PC in a heterogeneous PC + L system, and exploratory studies conducted in this direction showed the possibility and prospects of using OUzCE in remote low-frequency ultrasonic capillary flaw detection.

[0056] The history of the use of sound-capillary processes in this area to date is as follows. In the 1960-80s, Soviet scientists led by Academician E.G. Konovalov [7 et al.] discovered an effect manifested in processes associated with the movement of liquids in capillaries, namely the ultrasonic capillary effect (UcCE), which is a special type of unidirectional flows in the direction of ultrasound propagation, differing from the known ones - anomaly high speed and the fact that it occurs in capillary channels. It implements the phenomenon of an anomalously large, in comparison with radiation forces, increase in the depth and speed of liquid penetration into the channel of a capillary buried in a liquid, under the action of ultrasound acting on its base. It was shown that the effect of UcCE can manifest itself in capillary systems of both inanimate and animate nature.

[0057] At the same time, in the field of bioengineering, the staff of the Republican Research Laboratory of Biomedical Technologies and Possibilities of the Omsk Polytechnic Institute, in cooperation with the Department of Biomedical Technologies and Possibilities of the Bauman Moscow State Technical University, developed a direction related to the study of the mass transfer of biological fluids and medicinal solutions in heterogeneous systems of capillary-porous bio-objects or their models when exposed to low-frequency ultrasound energy. Where, under the influence of harmonic oscillations of the low-frequency range and high intensity, a regime of developed cavitation is realized, allowing the manifestation of the "reverse" ultrasonic capillary effect (OUzCE) [8, etc.]. Already in the first experiments conducted in 1978-80., associated with the distant processing of biological tissues by low-frequency ultrasound (f = 26.5 kHz, ξ = 30-60 μm and more), in a liquid medium and without it, it was shown that along with the manifestation of the well-known ultrasonic capillary effect (UzCE), which consists in an anomalous increase in the height of the liquid rise in the capillaries, in the direction of ultrasound propagation, a similar effect is observed, an anomalous increase in the height of the liquid rise in the capillaries, but in the direction opposite to the propagation of ultrasound [8-11 and others]. For the first time, it was established that the sound-capillary effect, depending on the technological schemes for introducing high-intensity ultrasonic vibrations and the design of waveguide devices, can have its manifestation both in the form of the well-known "direct" ultrasonic capillary effect - UzCE, and in the form of the "reverse" ultrasonic capillary effect - OUzCE, initiated, as a rule, remotely, i.e.e. at a resonant distance from a heterogeneous capillary-porous system containing liquid in the insonification region. Thus, we have the fact of the presence and manifestation of two sides of one phenomenon, i.e. the acoustic capillary effect, which significantly expands the functionality of modern technologies for various branches of science, engineering and technology, including in the direction of the development of combined capillary methods of non-destructive testing. Therefore, it is promising to use the capabilities of the "reverse" ultrasonic capillary effect - OUzCE for remote "opening of the capillary" in the presence of a liquid "plug", its movement and displacement (extraction) from the capillary by ultrasonic drainage, for example, in a heterogeneous system of PC + G (the PC + G system - a "plug" of liquid, etc.). To confirm the feasibility of implementing the claimed method of remote low-frequency ultrasonic capillary flaw detection, we provide examples of its implementation, where:

[0058] - using example 1 (Fig. 12-Fig. 14), carried out on experimental setup I, the possibilities of low-frequency ultrasonic impregnation of a solution of penetrant 8 into a sample of a capillary-porous system (CPS) are shown, and then distant extraction from it by ultrasonic drainage of a solution of penetrant 8 + developer-reagent 9, for example, in the form of an aerosol formed due to OUzCE, initiated remotely by a waveguide - “radiating disk”;

[0059] - using example 2 (Fig. 15-Fig. 17), implemented on experimental stand I, the following possibilities are shown on a sample model of the system (ZЁZh+PK+Zh), including liquid “plugs” (hereinafter referred to as the sample model (ZЁZh+PK+Zh), realizing:

[0060] - low-frequency ultrasonic impregnation of penetrant solution 8 into a sample model (ZYOZh+PK+Zh), along the trajectory of the annular weld, where hidden capillary defects may be;

[0061] - initiation of the OUzKE during remote extraction of a liquid medium from a defect(s) of a model sample (ZYoZh+PK+Zh) after applying developer-reagent 9 to its circumferential weld seam. In this case, the dynamics of the manifestation of the defect(s) indication and the reduction of the full recording cycle, indicating the presence of a capillary level defect, were assessed.

[0062] Example 1. An assessment of the possibility of low-frequency ultrasonic impregnation of penetrant 8 into a sample of a capillary-porous system (CPS), and then distant extraction from it by ultrasonic drainage of a solution of indicator penetrant 8 + developer-reagent 9, implemented by OUzKE, initiated remotely by a waveguide - “emitting disk”, was carried out using experimental stand I (Fig. 12-Fig. 14).

[0063] For this purpose, a sample of KPS 2 in the form of branched pore-capillaries (h обр =8 mm; ∅ пор=2-5 μm), located in Petri dish 14, on the surface of which a capillary-porous pad 7 saturated with a solution of indicator penetrant 8 was placed (Fig. 13a and Fig. 13b). The waveguide-“radiating disk” 5 (group 5) was brought to the surface of the KPS 2 sample, in the resonance mode and normal to the surface, ultrasonic impregnation of the penetrant solution 8 was carried out by intermittent contact sonication (Fig. 13b and Fig. 13c) with high-intensity ultrasound. Parameters of the sonication mode: ultrasound frequency f = 26.5 kHz, sound pressure p рез. - about 130 dB, sounding time τ - about 3 sec / cm 2 sample KPS 2.

[0064] Then, the surface of the KPS 2 sample, saturated with a solution of penetrant 8, was dried and a developer-reagent 9 was applied to it using a spray bottle 10. Next, having selected the resonant distance L рез.between the KPS sample 2 and the radiating end of the waveguide - "radiating disk" 6 (group 6), this waveguide 6 was positioned distantly and normally relative to the surface of the KPS sample 2 and, after turning on the ultrasound, at resonance, the OUzCE was initiated, implementing accelerated distant extraction by ultrasonic drainage of penetrant 8 + developer-reagent 9 onto the surface of the KPS sample 2 (Fig. 13d, e, g, h). Parameters of the distant insonification mode: ultrasound frequency f = 26.5 kHz; sound pressure p рез. - about 150 dB; resonant distance L рез.between the emitting end of the waveguide - "emitting disk" 6 (group 6) and the surface of the KPS 2 sample within 1 / 8 ... 1 / 32 of the wavelength λ of ultrasound or the acoustic boundary layer. The initiation of the OUzCE, with distant insonification of the KSP 2 sample, was continued until the visually determined maximum exit of penetrant 8 onto the entire surface of the KSP 2 sample, amounting to no more than 15 seconds (Fig. 14), which is sufficient for the complete recording of the resulting indications indicating the presence of a defect (defects) in the capillary level.

[0065] Example 2. Evaluation of the feasibility of low-frequency ultrasonic impregnation of penetrant 8 into a sample of the model system (ZYoZh+PK+Zh), including liquid (Zh) "plugs" 15 (hereinafter referred to as the sample of the model system 15), implemented in the area of ​​the generatrix of the trajectory of the annular weld 15.3 by the waveguide-"emitting disk" 5 (group 5), where hidden capillary defects may be, and then the implementation of remote extraction from the sample of the model system 15, by ultrasonic drainage, of a solution of indicator penetrant 8 + developer-reagent 9, due to OUzKE, initiated remotely by the waveguide-"emitting disk" 6 (group 6). Also, the dynamics of the defect indication manifestation and the reduction of the full fixation cycle, indicating the presence of a capillary level defect, were evaluated. The experimental setup I (Fig. 15-Fig. 17) was used in the work. For this purpose (Fig. 15-Fig. 16a, b) a sample of the model system 15 in the form of a closed cylindrical container, composed of two metal pipes 15, was used.1 and 15.2, connected by a circumferential weld 15.3, which may have a capillary level defect in the form of permeable capillaries (PC), including liquid "plugs" (Zh), formed due to capillary absorption of liquid when it is supplied to the cavity of the sample of the model system 15 with subsequent removal, which was determined by the experimental program. The device for supplying and removing liquid is not shown). A capillary-porous gasket 7 with a solution of indicator penetrant 8 was placed on the surface of the region generatrix of the annular weld seam 15.3 of the sample of the model system 15. Then, the waveguide-"radiating disk" 5 (group 5) was brought to the surface of the sample of the model system 15 and, in the resonance mode, normal to the surface of the annular weld seam generatrix 15.3, ultrasonic impregnation of penetrant 8 was carried out into it by intermittent contact insonification of the gasket 7 with high-intensity ultrasound (Fig. 16b). Parameters of the insonification mode: ultrasound frequency f = 26.5 kHz; sound pressure p. рез.- about 130 dB; sounding time τ - about 3 sec / cm 2 surface of the weld seam generator 15.3.

[0066] Then, the surface of the weld seam 15.3, saturated with the penetrant solution 8, was dried and the developer-reagent 9 was applied to it using a spray bottle 10 (Fig. 16c, Fig. 16d).

[0067] Next, by selecting the resonant distance L рез. (Fig. 16d) between the surface of the generatrix of the weld seam 15.3 and the radiating end of the waveguide - "radiating disk" 6 (group 6), the waveguide was positioned distantly and normally relative to the generatrix of the weld seam 15.3. After turning on the ultrasound, at resonance, the OUzKE was initiated, implementing accelerated distant extraction, ultrasonic drainage, of a solution of penetrant 8 + developer-reagent 9 on the surface of the generatrix of the weld seam 15.3 of the sample of the model system 15 (Fig. 16e, f). Parameters of the distant insonification mode: ultrasound frequency f = 26.5 kHz; sound pressure p рез.- about 150 dB; resonant distance L рез. between the emitting end of the waveguide - "emitting disk" 6 (group 6) and the surface of the generatrix of the weld seam 15.3 of the sample of the model system 15 within the range of 1 / 8 ... 1 / 32 of the wavelength λ of ultrasound or the acoustic boundary layer. In this case, the initiation of the OUzKE during distant insonification of the surface of the generatrix of the weld seam 15.3 of the sample of the model system 15 was continued until the visually determined maximum exit of the penetrant 8 + developer-reagent 9 onto the insonified surface, amounting to no more than 15 seconds (Fig. 14), which is sufficient for the complete recording of the generated indications indicating the presence of a defect (defects) of the capillary level.

[0068] A preliminary assessment of the dynamics of the process of extraction of liquid plug in the PC+G area, realized by distant ultrasonic drainage, upon initiation of OUzCE (Fig. 17), showed its rather high productivity, at the initial stage of development of this apparently promising method of diagnosing capillary level defects, including media with a liquid phase.

[0069] The proposed method for remote low-frequency ultrasonic drainage of liquid-phase media can be used in flaw detection for non-destructive testing of various products, including for diagnosing defects in heterogeneous capillary-level structures, including liquid-phase media. This method, based on the use of OUzKE, enables ultrasonic drainage of liquid-phase media from capillary-level defects - surface and through discontinuities in the material of the tested objects and recording the resulting indicator traces visually, etc. [1] and relates to combined capillary flaw detection methods for testing products for leaks, etc.

[0070] The proposed method is implemented for non-destructive testing purposes using ultrasonic equipment manufactured in Russia. To date, the proposed technical solution has been implemented in the form of a prototype product - the "Ekstrakton-2MM" low-frequency ultrasonic device for remote low-frequency ultrasonic penetrant flaw detection", shown in Fig. 10. Two sets of the "Ekstrakton-2MM" product have been launched into production for subsequent technical testing, in accordance with the established procedure, at the appropriate accredited test facility. To organize the production of the product and its implementation in the acceptance testing system as an industrial product enabling the implementation of combined methods of penetrant flaw detection, design documentation and projects are being prepared: Specifications, Data Sheets, Product Operation Manuals, Trademark, etc., necessary when implementing measures to put the specified product into production, which meets the requirements of “industrial applicability”.

[0071] Sources of information

[0072] 1. GOST 18442-80. Group T59. Interstate standard. Non-destructive testing. Penetrant methods. General requirements. 1981.

[0073] 2. USSR Author's Certificate No. 469904 "Method of Tightness Testing". Class G01M 3 / 20. K.S. Kasayev, E.I. Khavroshkina, V.N. Naumov. Claimed 1971. Published 1975.

[0074] 3. Patent RU No. 2033605 “Method of capillary flaw detection.” Cl. G01N 21 / 91. L.N. Kobzareva. Announced 1992. Published 1995.

[0075] 4. Antonov A.A. Penetrant flaw detection: Guidelines. - M.: Russian State University of Oil and Gas named after. THEM. Gubkina, 2016. - P. 13.

[0076] 5. USSR Author's Certificate No. 1376014 "Method of Capillary Flaw Testing". Class G01N 21 / 91. A.M. Ovsyankin, V.I. Savchenko, V.V. Ushakov, et al. Claimed 1986. Published 1988.

[0077] 6. USSR Author's Certificate No. 641331 "Method of Capillary Flaw Testing". Class G01N 21 / 16. A.R. Baev, N.V. Dezhkunov, G.E. Konovalov, et al. Claimed 1976. Published 1979.

[0078] 7. Prokhorenko P.P., Dezhkunov N.V., Konovalov G.E. Ultrasonic capillary effect. - Minsk: Science and Technology, 1981. - 135 p.

[0079] 8. Pedtser V.V. Research of the process, development of technology and equipment for ultrasonic welding of dissimilar biological tissues in hearing improvement operations: Abstract of Cand. Sci. (Eng.) diss. - M. 1982. - 16 p.

[0080] 9. Pedtser V.V., Nikulin V.Ya., Loshilova L.V. et al. Problems of engineering biomedicine / Proceedings of the Bauman Moscow State Technical University. - M., 1982. - No. 378. - P. 143-151.

[0081] 10. Author's certificate No. 1461466 "Device for treating infected wounds". Class A61M 1 / 00. V.V. Pedtser, Yu.V. Seleznev, S.N. Afanasyev, G.G. Sergienko, et al. Claimed 1986. Published 1989.

[0082] 11. Pedtser V.V. et al. On the mechanism of the "reverse" ultrasonic capillary effect and its use in the processing of biological tissues. Omsk Polytechnic Institute. - Omsk, 1987. - 29 p. - Dep. in VINITI. - M. - No. 6411-B87.

Claims

1. A method of remote low-frequency ultrasonic capillary flaw detection, carried out during inspection of a product for the presence of capillary level defects containing liquid "plugs", including the following stages: cleaning the inspection surface of the product, treating it with a cleaner, impregnating it with an indicator penetrant; removing excess penetrant from the inspection surface by wiping or rinsing with a cleaner;application of a developer and fixation of indications, characterized in that at the stage of impregnation of the test surface area with a weld seam with an indicator penetrant, a capillary-porous pad with a penetrant solution is placed on it and, in resonance mode, normally to the surface, ultrasonic impregnation of the penetrant introduced into the weld seam in the test area is carried out by intermittent contact sounding with a waveguide - a "radiating disk", the front radiating end of the working part of which, in the form of a paraboloid of revolution, is made without drainage nozzle channels, the parameters of sounding with high-intensity ultrasound at the stage of ultrasonic impregnation of the penetrant: frequency f = 26.5 kHz, sound pressure p; рез - about 130 dB, sounding time - about 3 s / cm 2welded seam, then at the stage of development of possible defects of the capillary level, carried out after removal from the surface of the penetrant control and application of the developer, the “reverse” sound-capillary effect is initiated, in resonance mode and normally to the surface, realizing the extraction of the contents of the defect of the capillary level by ultrasonic drainage, carried out by a waveguide - “radiating disk”, the front radiating end of the working part of which, in the form of a paraboloid of revolution, is made with drainage nozzle channels, while the parameters of high-intensity ultrasound at the stage of development of possible defects of the capillary level are the following: frequency f = 26.5 kHz, sound pressure p рез. - about 150 dB, the resonant gap between the front radiating end of the waveguide - the “radiating disk” - and the weld section on the control surface is within 1 / 8...1 / 32 of the wavelength ultrasound or acoustic boundary layer, excluding contact of the front emitting end with the weld on the surface of the product being tested.

2. The method according to paragraph 1, characterized in that the initiation of the “reverse” sound-capillary effect during distant sounding of the interested area of ​​the weld seam trajectory is continued until a time sufficient for the complete recording of the indication(s) indicating a defect(s) in the capillary level in the weld seam.

3. The method according to paragraph 1, characterized in that a capillary-porous pad made of an absorbent non-woven fibrous material is used as the sorbent element, on the one hand, performing the function of a penetrant depot for its ultrasonic impregnation in the area of ​​the weld seam in the control section, as well as a sorption element for the contents extracted by ultrasonic drainage from defects of the capillary level, initiated by the “reverse” sound-capillary effect.

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