UNSTEADY OPERATING MODES OF THE MAIN DRIVE UNIT OF A MACHINE-TOOLS FOR SOLID RAILWAY WHEELS PROCESSING
DOI:
https://doi.org/10.15802/stp2018/132960Keywords:
railway wheel, wheel-processing machine, machine drive unit, dynamic loads, vibrations, transitional processesAbstract
Purpose. The paper deals with determining the conditions of the dynamic overload formation for a drive unit in the wheel-processing machine in various unsteady operating modes and suggests ways to reduce it. Methodology. The problem was solved by creating a dynamic computational multi-mass chain model followed by modeling of its loading by external force options, the values of which were obtained by analytical and experimental methods. The solution to equations of motion with determining the load of the drive unit in the transient acceleration mode and in the tie-in one was carried out by means of MathCad. Findings. The design scheme for the drive unit of the rotational movement of the machine faceplate is represented by a linear three-mass row system with two elastic connections and with three absolute degrees of freedom. The analytical determination of the cutting force moments takes into account changes in the kinematic parameters of the cutting regime when machining the different sections of the profile with cup-tip tool. The worst case of load application is accepted with simultaneous insertion of tools. The equivalent torque of the cutting forces is defined as the sum of the moments from each of the tools at multi-cut machining. The moments of elasticity of bonds in the steady state of the machine drive unit are determined. Dynamic loads with coefficients of dynamism in the bonds Kd12 = 1.13 and Kd23 = 1.04 are insignificant in the tie-in mode and rapidly decrease their value. Absolute values of the twisting elastic moment in the C23 bond in the start-up mode are insignificant and much less than the values of the steady load. Using the method of calculation and experimental research, a significant dynamic overload of the machine drive unit in the mode of rheostat start-up by a directcurrent motor was established. The reactive elastic moment with the periodic change is 2.7 times higher than the nominal moment of steady processing regime. Originality. Authors created the elastic dynamic model of the machine drive unit for the processing of railway wheels. In accordance with the model, the equations of mass motion and bond loading are compiled and solved. The theoretical conditions for reducing the drive unit loading are determined. Practical value. Based on the simulation of the transient drive start-up process, significant overloads of its elements have been determined. They are several times higher than the response of elastic bonds during cutting. To prevent this, it is recommended to change the mode of multistage starting of the engine with a decrease of the starting current by at least two times up to a value of not more than 1 200 A.
References
Adamiya, R. S., & Loboda, V. M. (1984). Osnovy ratsionalnogo proektirovaniya metallurgicheskikh mashin. Moscow: Metallurgiya. (in Russian)
Kolesa sutsilnokatani. Tekhnichni umovy, DSTU GOST 10761:2016 (2016). (in Ukranian)
Zdanevich, V. A., & Pogrebnyak, R. P. (1995). Struktura i ratsionalnoe proektirovanie privoda stanka modeli 1B502 dlya obrabotki zheleznodorozhnykh koles. Metallurgicheskaya i gornorudnaya promyshlennost, 2, 64-67. (in Russian)
Zdanevich, S. V., Yermokratev, V. A., & Zdanevich, S. S. (2015). Sistemnaya dinamika privodov shestivalkovykh trubopravilnykh mashin. Metallurgical and Mining Industry, 7, 137-142. (in Russian)
Kedrov, S. S. (1978). Kolebaniya metallorezhushchikh stankov. Moscow: Mashinostroenie. (in Russian)
Kozhevnikov, S. N. (1986). Dinamika nestatsionarnykh protsessov v mashinakh. Kiev: Naukova dumka. (in Russian)
Levin, A. I. (1978). Matematicheskoe modelirovanie v issledovaniyakh i proektirovanii stankov. Moscow: Mashinostroenie. (in Russian)
Orlikov, M. L. (1989). Dinamika stankov. Kiev: Vishcha shkola. (in Russian)
Petrakov, Y. (2016). Simulation of chatter suppression for lathe machining. Journal of Mechanical Engineering of the National Technical University of Ukraine «Kyiv Polytechnic Institute», 2(77), 119-124. doi: 10.20535/2305-9001.2016.77.78960 (in Russian)
Pogrebnyak, R. P. (2017). Frequency analysis of elastic system of main drive of machine for railway wheels turning. Problems of computational mechanics and strength of structures, 27, 129-136. (in Ukranian)
Pogrebnyak, R. P. (2017). Elastic nonlinear dynamics of motion of slide of vertical turning machine for working of solid-rolled railway wheels. Science and Transport Progress, 4(70), 98-105. doi 10.15802/stp2017/109606 (in Ukranian)
Pogrebnyak, R. P. (2012). Eksperimentalnoe issledovanie formy prokatannoy zagotovki zheleznodorozhnogo kolesa. Proizvodstvo prokata, 2, 29-33. (in Russian)
Push, V. E. (1977). Konstruirovanie metallorezhushchikh stankov. Moscow: Mashinostroenie. (in Russian)
Rivin, Y. I. (1966). Dinamika privoda stankov. Moscow: Mashinostroenie. (in Russian)
Strutynskyi, V. B., & Perfilov, I. V. (2015). Vibratsiini protsesy mekhanichnoi obrobky: Monohrafiia. Kyiv: Khimdzhest. (in Ukranian)
Strutynskyi, V. B. (2001). Matematychne modeliuvannia protsesiv ta system mekhaniky. Zhytomyr: ZhITI. (in Ukranian)
Chao, X., Jianfu, Z., Dingwen, Y., Zhijun, W. & Pingfa, F. (2015). Dynamics prediction of spindle system using joint models of spindle tool holder and bearings. Journal of Mechanical Engineering Science, 229(17), 3084-3095. doi: 10.1177/0954406215569588 (in English)
Gegg, B. C., Suh, C. S., & Luo, A. C. J. (2011). Machine Tool Vibrations and Cutting Dynamics. doi: 10.1007/978-1-4419-9801-9 (in English)
Bosheng, Y., Weiwei, X., Kuanmin, M., & Bin, L. (2017). Hybrid analytic-experimental modeling for machine tool structural dynamics. The International Journal of Advanced Manufacturing Technology, 90(5-8), 1679-1691. doi: 10.1007/s00170-016-9507-2 (in English)
Brecher, C., Fey, M., Tenbrock, C., & Daniels, M. (2015). Multipoint Constraints for Modeling of Machine Tool Dynamics. Journal of Manufacturing Science and Engineering, 138(5), 117-124. doi: 10.1115/1.4031771 (in English)
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