Dyrda V.I., Kobets A.S., Bulat Ie.A., Slobodian S.B., Lysytsia M.I., Sokol S.P., Lapin V.A., Ahaltsov H.M. Present problems of vibration isolation in heavy mining machines at long-term cyclic loads

Geoteh. meh. 2021, 157, 223-238

https://doi.org/10.15407/geotm2021.157.223

 

PRESENT PROBLEMS OF VIBRATION ISOLATION IN HEAVY MINING MACHINES AT LONG-TERM CYCLIC LOADS

1Dyrda V.I., 2Kobets A.S., 3Bulat Ie.A., 4Slobodian S.B., 1Lysytsia M.I., 2Sokol S.P., 5Lapin V.A., 1Ahaltsov H.M.

1Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine, 2Dnipro State Agrarian and Economic University, 3Prydniprovsky Scientific Center of National Academy of Sciences of Ukraine and of Ministry of Education and Science of Ukraine, 4State Agrarian and Engineering University in Podilya, 5Kazakh Research and Design Institute of Construction and Architecture

UDC 622.7:[531.3+531.6]

Language: English

Abstract. An integrated approach was used, including the construction of a mathematical model and the results of lengthy industrial tests of heavy mining machines with rubber elastic bonds.
The issues of vibration isolation of heavy machines operating in extreme conditions, i.e. with prolonged cyclic loads and the influence of an external aggressive environment inherent in mining and processing enterprises. As an example, we con-sider vortex mixers with a vibration isolation system containing rubber elements. During long-term operation, the mass of the mixer does not remain constant; its increase is associated with the sticking of the initial product on the moving parts of the ma-chine. The location of such machines in the sinter factory at + 10.4 m, as well as the change in time of rotational symmetry of the drum rotation imposes certain requirements on the vibration isolation system: the system must be "soft" and stable in time, i.e. during 9-10 years of operation, its stiffness and dissipative parameters should not go beyond the permissible values. In order to reduce the aging effect, type 2959 rubber based on natural caoutchouc with a reinforced protective group was used, while the instability of the main mechanical parameters was taken into account in the developed theory of vibration isolation of machines.
On the basis of the developed simulation model and the Boltzmann-Volterra integral relations with kernels of relaxation and aftereffect, an equation was worked out, which made it possible to take into account the rubber viscoelastic properties in full volume; in this equation, stiffness operator of elastic suspension in the machine is written by using fractional exponential function of the Yu. Rabotnov's type; on the basis of the mathematical model, the basic parameters of the machine under the study were calculated; in particular, for the vortex mixer, the time dependences of amplitude of the mixer housing vibrations and coefficient of vibration isolation efficiency were calculated with taking into account aging of elastic link material in the ma-chines; the calculation results were compared with the results of industrial tests of the vortex mixer operation lasting for 16 years. The theory and method for calculating vibration isolation systems with rubber elastic links for heavy mining machines were developed with taking into account material structure changes due to the effects of aging.
The paper considers an example of calculating the mixer vibration isolation system taking into account rubber aging; the magnitude of the change in time of the main mechanical parameters was obtained experimentally over 16 years. This made it possible to determine temporary changes in the amplitude of oscillations of the mixer body and the coefficient of efficiency of the vibration isolation system. It was shown that the mixer vibration isolation system remained effective for 9-10 years, after which the mechanical characteristics of the rubber went beyond the permissible values and the system lost its functional pur-pose, and the amplitude of the mixer body exceeded the existing sanitary standards.
Keywords: vibration isolation of machines, Boltzmann-Volterra integral relations, Rabotnov function, rubber aging ef-fects.


REFERENCES:

1. Bulat, A.F., Dyrda, V.I., Zvyagil’skiy, Ye.L. et al. (2016), Elastomery v gornom dele [Elastomers in mining], Naukova dumka, Kyiv, Ukraine.

2. Zabolotny, K.S., Sirchenko, A.A. and Zhupiev, A.L. (2016), “Design and analysis of the oscillating system’s of self-propelled feeding bin BPS-940”, Vibration in engineering and technology, no. 2 (82), pp. 16-21, http://vibrojournal.vsau.org/files/pdfa/3011.pdf

3. Yaroshevich, N.P., Zabrodets, I.P. and Yaroshevich, T.S. (2015), “Dynamics of vibrating machines starting with unbalanced drive in case of bearing body flat vibrations”, Scientific Bulletin of National Mining University, no. 3, pp. 39-45. https://doi.org/10.4028/www.scientific.net/AMM.849.36

4. Ilin, S.R., Samusia, V.I., Ilina, I.S. and Ilina, S.S. (2016), “Influence of dynamic processes in mine hoists on safety of exploitation of shafts with broken geometry”, Scientific Bulletin of National Mining University, no. 3, pp. 48-53.

5. Dyrda, V.I., Kobets, A.S., Bulat, Ie.A., Lapin, V.A., Lysytsia, M.I., Ahaltsov, H.M. and Sokol, S.P. (2019), “Vibroseismic protection of heavy mining machines, buildings and structures” E3S Web of Conferences, International Conference Essays of Mining Science and Practice, vol. 109 (2019). https://doi.org/10.1051/e3sconf/201910900022

6. Dyrda, V.I., Kobets, A.S., Pukhalskyi, V.N., Kozub, Yu.H. and Chernii, O.A. (2019), “Dynamics of vibratory partitioned feeders for the uranium ore drawing and feeding”, E3S Web of Conferences, International Conference Essays of Mining Science and Practice, vol. 109 (2019). https://doi.org/10.1051/e3sconf/201910900023

7. Voloshyn, O.I. and Riabtsev, O.V. (2019), “Some important aspects of rock mechanics and geomechanics”, E3S Web of Conferences, International Conference Essays of Mining Science and Practice, vol. 109 (2019). https://doi.org/10.1051/e3sconf/201910900114

8. Bulat, A.F., Dyrda, V.I., Lysytsya, M.I. and Grebenyuk, S.M. (2018), “Numerical Simulation of the Stress-Strain State of Thin-Layer Rubber-Metal Vibration Absorber Elements Under Nonlinear Deformation”, Strength of Materials, no. 3 (50), pp. 387-395, https://doi.org/10.1007/s11223-018-9982-9


About the authors:

Dyrda Vitalii Illarionovych, Doctor of Technical Sciences (D. Sc.), Professor, Head of Department of Elastomeric Component Mechanics in Mining Machines, Institute of Geotechnical Mechanics named by N. Poljakov NAS of Ukraine, Dnipro, Ukraine,  This email address is being protected from spambots. You need JavaScript enabled to view it.

Kobets Anatolii Stepanovych, Doctor of Public Administration, Professor, Rector, Dnipro State University of Agriculture and Economics, Dnipro, Ukraine,  This email address is being protected from spambots. You need JavaScript enabled to view it.

Bulat Ievgeniia Anatoliivna, Doctor of Science of Law, Senior Researcher, Prydniprovsky Scientific Center of the National Academy of Sciences of Ukraine and the Ministry of Education and Science of Ukraine, Professor of Department of Civil, Labour and Commercial Law, Oles Honchar Dnipro National University, Dnipro, Ukraine,  This email address is being protected from spambots. You need JavaScript enabled to view it.

Slobodyan Sergii Borysovych, Candidate of Technical Sciences, Associate Professor of Department of General Technical Disciplines and Physics, State Agrarian and Engineering University in Podilia, Kamianets-Podilskyi, Ukraine,  This email address is being protected from spambots. You need JavaScript enabled to view it.

Lysytsia Mykola Ivanovych, Candidate of Technical Sciences (Ph. D.), Senior Researcher, Senior Researcher in Department of Elastomeric Component Mechanics in Mining Machines, Institute of Geotechnical Mechanics named by N. Poljakov NAS of Ukraine, Dnipro, Ukraine,  This email address is being protected from spambots. You need JavaScript enabled to view it.

Sokol Sergii Petrovych, Candidate of Technical Sciences (Ph.D.), Associate Professor, Dnipropetrovsk State Agrarian and Economic University, Dnipro, Ukraine,  This email address is being protected from spambots. You need JavaScript enabled to view it.

Lapin Vladimir Alekseevich, Candidate of Technical Sciences (Ph.D.), Director of Center for Scientific Research in Building Industry, Corresponding Member of International Engineering Academy and National Engineering Academy of the Republic of Kazakhstan, Kazakh Research and Design Institute of Construction and Architecture, Almaty, Kazakhstan,  This email address is being protected from spambots. You need JavaScript enabled to view it.

Ahaltsov Hennadii Mykolaiovych, Master of Science, Junior Researcher of Department of Elastomeric Component Mechanics in Mining Machines, Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Science of Ukraine, Dnipro, Ukraine,  This email address is being protected from spambots. You need JavaScript enabled to view it.