NON-DESTRUCTIVE TESTING OF MATERIAL CONDITION FRICTION STEAM OF WWER PUMPS

  • В.И. Ерофеев Erofeev Mechanical Engineering Research Institute of the Russian Academy of Sciences – Branch of Federal Research Center “Institute of Applied Physics of the RAS”
  • А.В. Иляхинский Ilyakhinskii Mechanical Engineering Research Institute of the Russian Academy of Sciences – Branch of Federal Research Center “Institute of Applied Physics of the RAS”
  • В.М. Родюшкин Rodyushkin Mechanical Engineering Research Institute of the Russian Academy of Sciences – Branch of Federal Research Center “Institute of Applied Physics of the RAS”
  • И.А. Иляхинский Ilyakhinskii JSC “OKBM Afrikantov”, Nizhny Novgorod, Russian Federation
  • С.Н. Пичков Pichkov JSC “OKBM Afrikantov”, Nizhny Novgorod, Russian Federation
  • А.А. Хлыбов Khlybov Nizhny Novgorod State Technical University n.a. R.E. Alekseeva, Nizhny Novgorod, Russian Federation
DOI: https://doi.org/10.32326/1814-9146-2022-84-3-376-385
Keywords: silicon carbide material, electrical conductivity, elastic waves, velocity, attenuation, eddy currents, microstructure

Abstract

The possibility of using non-destructive methods for monitoring the state of silicon carbide materials in friction pairs of pumps of WWER installations has been experimentally demonstrated which makes it possible to identify potential sites of future possible destruction on the working surface of bearings. The paper describes the methodology for studying the acoustic properties and electrical conductivity of products made of silicon carbide composite. The relationship between the electrical conductivity and acoustic parameters of the material of friction pairs of WWER installations with the characteristics of the microstructure of the material under study has been experimentally established. As the hardware part of the emission and reception of acoustic pulses Krautkramer USN 52 device certified by the State Standard of Russia with emitters and receivers of longitudinal and transverse waves was used. To assess the electrical conductivity a VT2 eddy current electrical conductivity meter with a 5 kHz clamp-on transducer was used which has a pointer transducer with a uniform scale not graduated in electrical conductivity units as an indicator device. Measurements of the electrical conductivity and velocity of longitudinal and transverse waves polarized along the radius at the same points of the working surface of the bearing showed the coincidence of the nature of the change in the measurement results. In this case, if the excess of the value of the velocity of longitudinal waves in the fracture zone over the average value for the entire working surface of the bearing is up to 30%, then for electrical conductivity it is 40%. By measuring the velocities of transverse waves with polarization parallel and perpendicular to the radius, the presence in the material of bearings that have not passed tests under conditions of high pressure and temperature of significant internal stresses provoking the appearance of destruction (chips) on the working surface has been established.

Published
2022-09-30
Issue
Vol 84 No 3 (2022): Problems of strength and plasticity
Section
Articles