Sharif University of Technology Scientia Iranica 1026-3098 27 1 2020 02 01 Analysis of change in the state of hydraulic drive of machines in operation according to the diagnostic results 295 301 20587 10.24200/sci.2018.50340.1644 EN N.G. Grinchar Department of Track Machines, Construction Machines and Robot Systems, Russian University of Transport, 127994, 9 Obrazcova Str., Moscow, Russian Federation. P.A. Sorokin Department of Track Machines, Construction Machines and Robot Systems, Russian University of Transport, 127994, 9 Obrazcova Str., Moscow, Russian Federation. V.A. A. Karpychev Department of Machine Science, Design, Standardization and Certification, Russian University of Transport, 127994, 9 Obrazcova Str., Moscow, Russian Federation. K.A. Sergeev Department of Non-Traction Rolling Stock, Russian University of Transport, 127994, 9 Obrazcova Str., Moscow, Russian Federation. Journal Article 2018 01 24 Technical diagnostics is a sphere of knowledge embracing theory, methods and means for defining the technical state of the objects. It is necessary for provision of security, functional reliability and efficiency of the technical object operation, as well as for reduction of the costs for its technical maintenance and reduction of the idle time losses caused by failures and premature shutdowns for maintenance. Therefore the objective of the paper is to analyze the change in the state of hydraulic drive of machines while in operation according to the diagnostic results. In order to achieve the set objective the authors used various experimental methods. The paper considers mutual influence of maintenance and technical diagnostics of hydrostatic drives of construction, track and some other mobile machines. It is shown that introduction of technical diagnostics allows transferring from the system of planned preventive repairs to the system of servicing the machines according to their actual technical state, which allows completely using the resource of a series of expensive aggregates. The authors described several main basic characteristics of change in the volume effectiveness of the hydraulic sets while in operation. https://scientiairanica.sharif.edu/article_20587_1f33547aa3b27d70cf3458d3e127cc77.pdf