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Questions related to adjusting an ultrasonic flaw detector using cylindrical bores in reference and tuning samples are considered with allowance for the specific features of single- and double-crystal testing schemes, including when a bore is sonified perpendicularly and at an angle to its axis. Requirements have been determined in each scheme to the drilling diameter and the duration of ultrasonic pulses such that signals specularly reflected from the drilling surface not be distorted by creeping and other signals diffracted by the cylinder. It is indicated that under these conditions, cylindrical drilling can be used not only for adjusting the "flaw detector-transducer" system, but also for calibrating the time scan, verifying the accuracy of the depth gage, and checking the flaw-detector attenuator. This approach makes it possible to simplify the construction of measures and tuning samples by eliminating excess reflectors. Examples are given in the echo and TOFD techniques for testing welded joints using traditional and special double-crystal schemes with different probes orientations. [ABSTRACT FROM AUTHOR]

We consider the problem of automated diagnostics of the state of the anode steel pin in Söderberg electrolytic cell with top current supply, which is the main current-supply element in metallurgical units. It is proposed to use digital cameras to contactlessly monitor the shape and dimensions of the working part of the anode post. The images of anode post sections taken in two mutually perpendicular planes allow evaluating the shape and size of the anode post. The possibility of using digital cameras with a resolution of 2 and 5 MP as recording devices is considered. The components of the error of the system for monitoring current-carrying rods located outside the electrolysis shop, in the rod-cleaning area, have been identified. Main attention is paid to analyzing instrumental errors of the system. Possible configurations of the monitoring system are examined, and a method is described for compensating for the main component of the error in nontelecentric optical systems, the positioning error. [ABSTRACT FROM AUTHOR]

A method is described for measuring the relative magnetic permeability of monolithic electrically conductive annular samples in an alternating magnetic field with a frequency of 50 Hz to 5 MHz, using toroid coils wound round the samples. The reasons are indicated for the significant influence that the electrical conductivity of the samples has on the results of measurements. The proposed procedure makes use of a correction coefficient, which depends on the specific electrical conductivity of the sample and is determined from a two-dimensional calibration table obtained by finite element modeling of this measurement problem, with allowance for the deviation of the geometrical dimensions of the measured sample from the dimensions of the sample in the finite element model. [ABSTRACT FROM AUTHOR]

We consider the issues of expanding the range of measuring the shape and determining the deformation of a surface by wavefront detection methods such as holographic and speckle interferometry and speckle photography, based on a two-beam Jamin interferometer equipped with an image shifting device. A design has been developed for the two-beam interferometer with the device for shifting images in channels based on synchronously tilted plane-parallel plates. A technique for processing shear interferograms is decsribed. The accuracy of measuring the spacing of fringes in the interference pattern by Fourier-transform and wavelet-analysis based algorithms is studied. A block diagram of an automated device for interpreting speckle interferograms by the phase method based on a He–Ne laser in a magnetic field with a Zeeman frequency shift has been developed. It is shown that the accuracy of measuring the spacing of interference fringes can be as high as 0.02 of the interference fringe width. [ABSTRACT FROM AUTHOR]

Results of trialing eddy-current testing techniques, validated on real operational defects and realistic artificial defects in the most critical parts, are presented. Significant differences have been established in the detectability of defects by various devices used in the industry according to various technological documentation. A method is proposed for standardizing sensitivity that should improve the reproducibility of the results of eddy current testing. [ABSTRACT FROM AUTHOR]

We consider issues related to constructing industrial linear-size monitoring devices using an optoelectronic system (OES) based on National Instruments (NI) smart cameras. A prototype of the experimental setup for measuring the width of a calibrated tunable monochromator slit has been developed. Algorithms have been investigated for measuring linear dimensions in the slit image using the techniques of differentiating the illuminance distribution, determining the best image boundary lines, and locating maxima on the curves of continuous-wavelet-transform (CWT) coefficients. The results of measuring linear dimensions using various algorithms are compared in cases where the image quality is affected by influencing factors. It is shown that the accuracy of linear sizing with a smart camera reaches 0.2 pel (1 μm in the range of 3 mm). [ABSTRACT FROM AUTHOR]

We consider theoretical foundations for the nondestructive testing of large-sized structures and structures made of structurally inhomogeneous composite materials by the method of elastic-wave velocity hodograph. The theoretical fundamentals of the method of elastic-wave velocity hodograph are presented for a single-layer medium, and the propagation of low-frequency elastic waves in a homogeneous isotropic single-layer medium is described. Based on the research, recommendations are given on detecting defects and determining the speed of propagation of elastic waves in a single-layer medium; this allows nondestructive testing of the physical and mechanical characteristics of the material in the layer and flaw detection and thickness gaging in large-sized structures and structures made of coarse-grained and composite materials. [ABSTRACT FROM AUTHOR]

It has been shown theoretically and experimentally that locally magnetizing rebar through a protective layer of concrete makes it possible to determine both the depth of the protective layer of concrete and the diameter of rebar based on stray magnetic fields regardless of the magnetic properties of steel that rebar is made of. [ABSTRACT FROM AUTHOR]

Issues of estimating the instrumental errors of a device for in-process control of the position of a rotating plane, based on analyzing the coordinates of the points on the trajectory of movement of a luminous mark in a rotating mirror are considered. The main dependences describing the trajectory of the luminous mark in the rotating mirror are provided, the schemes in which errors are formed are considered, some assessments of these errors are given, and the main components of the errors are highlighted. Based on the research, recommendations are given on choosing the parameters of a device that implements the control of the position of the rotating plane. [ABSTRACT FROM AUTHOR]

Thickness measures for electrically conductive coatings applied to electrically conductive bases are described, for which not only geometrical but also electrophysical parameters such as the specific electrical conductivity and complex relative permeability of the measure base and the specific electrical conductivity of the measure coating are prescribed. The procedure and a technique for measuring the specific electrical conductivity of the base of a measure using the van der Pauw method, the complex relative magnetic permeability of metal on ring-shaped samples using a permeameter, a technique for transferring the value of this parameter to the measure base of an arbitrary shape with a flat surface, and also the procedure and a method for measuring the specific electrical conductivity of the coating-measure material with the use of an eddy current probe with a wave-like drive winding are described. [ABSTRACT FROM AUTHOR]

An experimental setup has been created that allows measuring the values of magnetic field components above the surface of a metal plate in automatic mode. The experimental setup takes the readings of magnetic Hall transducers and sends the processed information to a computer in the form of text and graphic files. Based on experimental data, a component of the measured magnetic field, the shape of surface defects in a plate made of steel 20 was determined using the technique of reconstructing the metal–air boundary along magnetic lines of force. The magnetic transducer, a three-axis digital Hall sensor ALS31300, took measurements over a defect-free metal surface. The nonlinear properties of the ferromagnet are taken into account. [ABSTRACT FROM AUTHOR]

The field and magnetic-inductance spatial distributions in plates that differ in geometric dimensions and magnetic properties, which were magnetized locally by U-shaped electromagnets of different standard sizes, were calculated using the finite element method. The magnetic-flux side scattering, which impedes the magnetization, was estimated qualitatively. Recommendations on designing magnetizing instruments, which are characterized by low side scattering, are given. [ABSTRACT FROM AUTHOR]

Dependences of the polarization characteristics of light reflected by various surfaces have been studied. A heterogeneous system was analyzed by the method of partitioning and physicomathematical modeling of the structure, with "effective substrate" or "effective layer" model used. A method for measuring the polarization of reflected radiation has been developed and its polarization characteristics have been studied experimentally. It is shown that for all samples, the azimuth of polarization of reflected light decreases with increasing the angle of radiation incidence. It has been established experimentally that light reflected from the samples under study remains virtually linearly polarized. [ABSTRACT FROM AUTHOR]

The possibilities and limitations of applying head and surface waves to ultrasonic inspection of articles manufactured by selective laser alloying are considered. The optimum angles have been determined for the generation of head and surface waves in a product made of the domestic EP648 powder. The peculiarities of revealing crack-like flaws by the ultrasonic echo method are demonstrated. [ABSTRACT FROM AUTHOR]