Baglai A. Development of scientific bases for determining the technical condition of rolling equipment using a stationary vibration monitoring system

Thesis submitted for obtaining the Doctor of Philosophy degree in Mechanical engineering sciences, speciality 133 – Industry engineering. – National Metallurgical Academy of Ukraine, Dnipro, 2021. The dissertation is devoted to the issues of substantiation and development of methods, methods, principles and systems of vibration monitoring and diagnostics of the technical condition (TC) of the equipment of the stands of a continuous broadband hot rolling mill, as well as checking their operability and efficiency in production conditions. In the dissertation work new scientifically substantiated theoretical and experimental results are obtained, which together are essential for solving the current scientific and technical problem of increasing the reliability of hot rolling mill equipment by developing methods, methods, principles and systems of vibration monitoring and diagnosing controlled vehicles. equipment. Scientific novelty of the obtained results:  for the first time for the case equipment of the drive line of each cage of the multicellular continuous state by measuring the data on the vibration field in the form of vibration velocity realization at 7-9 points during operating and idle mode, histograms and standard deviation;  for the first time on the basis of a large number of measurements for all stands established a statistical relationship of the relative delay time of the reaction of the drive line sections from the time of operation of the spindles (wear of bronze inserts) taking into account the rolled range. The maximum quantitative values of the delay time are determined, at the achievement of which it is recommended to carry out maintenance;  for the first time the concept of determination of a technical condition of the equipment by means of diagnostic signs which receive for two modes of work of a condition is proved and developed: a) capture of a strip by rolls and b) a steady mode of work;  it is established that the maximum value of the vibration velocity of the gear equipment of the gearbox and the gear stand during the capture of the strip by rollers is statistically related to the technical condition (wear of bronze liners) of the spindle joint and is a diagnostic feature. For the first time the correlation dependence of the maximum scope of vibration speed at capture of a strip by rolls on the static moment of rolling on a motor shaft is established;  for the first time the dependence of the time of propagation of the shock pulse through the strip that is rolled to the previous cage, taking into account the temperature of the metal and the intercellular distance. This allows you to use this dependence to assess the state of technology and equipment. The practical significance of the developed technique lies in the possibility of choosing the periods of purposeful vibration measurements, when the connection of diagnostic features with the condition of the equipment is most manifested, which increases the efficiency and reliability of the diagnostic process.