IDENTIFICATION OF DEFECTS SIZES EDDY-CURRENT CONTROl

2021 ◽  
pp. 16-19
Author(s):  
V. N. Gadalov ◽  
O. M. Gubanov ◽  
A. V. Filonovich ◽  
I. V. Vornacheva
Keyword(s):  
Eddy Current ◽  
Characteristic Size ◽  
Current Control ◽  
Current Transducer ◽  
Subsequent Calculation ◽  
The Difference ◽  
Eddy Current Transducer

A method is proposed for identifying the size of defects during eddy testing, which reduces the zones of uncertainty caused by errors in calculation and experiment. In order to reduce the uncertainty, as a criterion for comparing the theoretical and experimental dependences of the signal on the defect, one can use the difference in minimization of the squares of the deviation of the corresponding dependences. Using the method of simulating the signal of an eddy current transducer (ECP) from a defect, experiments were carried out in order to verify the method for identifying a characteristic size, a defect, with subsequent calculation of the customer’s risk.

scholarly journals INDUCTIVE PARAMETRIC EDDY-CURRENT TRANSDUCER (IPEP) FOR MEASURING ELECTRICAL AND TEMPERATURE PARAMETERS OF WASTEWATER FROM BREWING PRODUCTION

2021 ◽  
pp. 26-33
Author(s):  
Vadim Sebko ◽  
Volodymyr Babenko ◽  
Yevheniia Pyrozhenko
Keyword(s):  
Electrical Conductivity ◽  
Eddy Current ◽  
Test Tube ◽  
Specific Electrical Conductivity ◽  
Wastewater Sample ◽  
Current Transducer ◽  
Differential Scheme ◽  
The Difference ◽  
Glass Test Tube ◽  
Eddy Current Transducer

The possibility of using the theory of operation of a differential inductive parametric  eddy-current transducer (IPET) for measuring the electrical and temperature parameters of a sample of acidic and alkaline wastewater is investigated. The need for the development of new informative methods for measuring the physicochemical parameters of wastewater is proved, in the realization of which a promising method of purification is selected. On the basis of a differential scheme for switching on two parametric converters: with exemplary purified water and a converter in which a test tube with a sample of waste water from a brewing production is placed, a differential informative method for measuring the electrical and temperature parameters of the liquid under study is proposed, which is based on the analysis of the components of the difference signal of phase shift angles measured electrical components of the switching circuit signals. The basic relationships that describe the operation of the IPET with the sample of the controlled liquid are given. The scheme of switching on differential IPET with a liquid sample, which is placed in a glass test tube, is considered; the differential scheme provides for heating the sample during measurements to simulate the production conditions of brewing production. Universal transformation functions are given that relate the components of the IPET signals with the specific electrical conductivity χt.s. and the temperature t of the wastewater sample from brewing production, that is, the dependence of the phase difference signal Δj on the generalized parameter A and the dependence of the absolute increment in the specific electrical conductivity Δχ on the temperature t of the wastewater sample, in the investigated temperature range.

Noninvasive Electromagnetic Evaluation of Bjo¨rk-Shiley Heart Valves: Lifetime Prediction

2008 ◽  
Author(s):  
Raimond Grimberg ◽  
Adriana Savin ◽  
Shiu C. Chan ◽  
Rozina Steigmann ◽  
Lalita Udpa ◽  
...  
Keyword(s):  
Eddy Current ◽  
Heart Valves ◽  
Probability Of Detection ◽  
New Method ◽  
Lifetime Prediction ◽  
Prosthetic Heart Valves ◽  
In Vitro Experiments ◽  
Current Transducer ◽  
Eddy Current Transducer

Prosthetic heart valves of the Bjork-Shiley Convexo-Concave (BSCC) type have long been used extensively in implants; however, there have been reports of cases where one component of the valves failed, leading to the demise of the patient. This paper presents a new method for noninvasive electromagnetic evaluation for this type of valve, using an eddy current transducer with orthogonal coils. In vitro experiments have shown that discontinuities of outlet strut with depths equal or larger than 0.4mm can be detected with a probability of detection (POD) of 86.4%, and in the case of discontinuities with depth equal or larger than 0.6mm with POD of 97%.

scholarly journals Experimental Studies of an Eddy Current Transducer with Spatially Periodic Fields

2018 ◽  
pp. 45-50
Author(s):  
B. Gorkunov ◽  
S. Lvov ◽  
Tamer Shaiban ◽  
Y. Borysenko
Keyword(s):  
Eddy Current ◽  
Experimental Studies ◽  
Fixed Frequency ◽  
Current Transducer ◽  
Current Conductor ◽  
Translation Symmetry ◽  
Spatially Periodic ◽  
Transducer Output ◽  
Angular Coordinates ◽  
Eddy Current Transducer

The purpose of this study is to perform a comparative analysis of the experimentally obtained and calculated values of the measuring windings total EMF amplitudes of the eddy current transducer with spatially periodic fields when magnetic and nonmagnetic cylindrical product are placed in it. To realize this goal in the work, a transducer with translational symmetry of excitation magnetic field has been developed. Translation symmetry typical example is the field of a long current conductor. The paper considers quasi-static electromagnetic field with the wavelength that exceeds characteristic transverse dimensions of conductor and cylinder. As the study result it is seen a satisfactory coincidence of the calculated and experimentally obtained values of the EMF of the transducer output signal in the cases of the product absence and with variety of products. As for example for measuring windings with angular coordinates φ = 30° and 60° an error of voltage values difference is less than 10%. The study shows that the advantage of such transducers while operating on one fixed frequency is capability to perform the multi-parameter testing on account of processing of certain amount of some spatial harmonics of excitation field.

scholarly journals Numerical Simulation of Non-Destructive Remote Field Eddy Current Testing of Rolled Metal Tubes

2019 ◽  
pp. 46-55
Author(s):  
A.G. Efimov ◽  
N.R. Kuzelev ◽  
E.V. Martyanov ◽  
B.M. Kanter ◽  
A.E. Shubochkin
Keyword(s):  
Numerical Simulation ◽  
Eddy Current ◽  
Current Method ◽  
Eddy Current Testing ◽  
Eddy Current Method ◽  
Current Testing ◽  
Advantages And Disadvantages ◽  
Current Transducer ◽  
Non Destructive ◽  
Eddy Current Transducer

The first publications describing the physical principles of the non-destructive remote field eddy current testing method appeared about 30 years ago. This method allows to significantly expand the field of application of eddy current testing. However, due to the lack of a theoretical justification, this method did not get widespread use around the world. Domestic publications in this area are completely absent, and the descriptions given in few foreign publications often contradict each other. There are no results of full-scale simulation using numerical methods in available domestic and foreign sources. The distinctive feature of this method under consideration is the ability of detecting defects on the external (with respect to the eddy current transducer) side of the tested object, which is impossible for the classical eddy current method due to the limited eddy current penetration depth. The basics of the method were considered, the distinctive features were presented, and the advantages and disadvantages of remote field eddy current testing of metals were pointed out. A numerical simulation with the subsequent analysis of the obtained results has been carried out, the transducer design for remote field eddy current testing is given. The influence of various factors on the change in the added voltage of the signal coil of the eddy current transducer in the presence of a defect in the external wall of the tube was considered. Expressions that determine the optimal ratio of the diameters of the transducer and the tested product were obtained. The values of the test parameters and the limiting wall thickness of the tested ferromagnetic product were determined.

A Working of Eddy Current Transducers under Control of Ferromagnetic Pipes in Condition of Insufficient Magnetic Saturation

2013 ◽  
Vol 467 ◽  
pp. 528-530
Author(s):  
Kai Yu Hao ◽  
Vadim Miroshnikov
Keyword(s):  
Electromagnetic Field ◽  
Numerical Calculation ◽  
Eddy Current ◽  
Maxwell Equations ◽  
Control Sample ◽  
Magnetic Saturation ◽  
Method Of Calculation ◽  
Current Transducer ◽  
Object Of Control ◽  
Eddy Current Transducer

The numerical method of calculation of electromagnetic field in a control sample at a time of work of encircling eddy current transducer is offered. The method is based on a numerical solution of the two Maxwell equations, which connect a change of electrical and magnetic fields. It allows to make calculations taking into account the actual value of magnetic inductivity of metal and to get results in any form, convenient for further interpretations. For the calculation of the encircling eddy current transducer the equivalent circuit of defect as step junction is offered. The numerical calculation shows, that the greatest sensitivity of the transducer is achieved when the value of magnetic permeability of the object of control is approximately 10-30. Therefore, it is not necessary to lead the material of the object of control up to satiety, as it considered before.

scholarly journals Eddy Current Transducer with Rotating Permanent Magnets to Test Planar Conducting Plates

Sensors ◽  
2019 ◽  
Vol 19 (6) ◽  
pp. 1408 ◽  
Author(s):  
Tomasz Chady ◽  
Jacek Grochowalski
Keyword(s):  
Magnetic Fields ◽  
Eddy Current ◽  
Permanent Magnets ◽  
Eddy Currents ◽  
Nonuniform Distribution ◽  
Current Transducer ◽  
Different Depths ◽  
Hall Sensors ◽  
Eddy Current Transducer

In this paper, we present an eddy current transducer with rotating permanent magnets for the inspection of planar conducting plates. The transducer consists of a rotating head with permanent magnets, which is used to generate variable magnetic fields and thus induce eddy currents in the tested material. Two Hall sensors connected in a differential manner are used to detect a nonuniform distribution of eddy currents induced in a specimen containing a defect. To prove the usability of the transducer, a number of experiments were conducted on thick aluminum samples containing notches at different depths. Selected results of the achieved measurements are presented.

High sensitivity differential eddy current transducer

2007 ◽  
Vol 25 (1-4) ◽  
pp. 369-373
Author(s):  
Tomasz Chady ◽  
Przemysław Łopato ◽  
Ryszard Sikora ◽  
Mieczysław Komorowski
Keyword(s):  
Eddy Current ◽  
High Sensitivity ◽  
Current Transducer ◽  
Eddy Current Transducer
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