The Resource of Movable Sealing Joints with the O-Ring Seal

Abstract

Introduction. The problem of reliability of hydraulic drives sealing joints remains unsolved. However, the current level of computer modeling tools development allows us to solve effectively the problems of their longevity by replacing laborious experiments with high-performance computing. This paper presents the results of the approbation of the author's methodology for realizing computational approaches to determining the life of sealing joints on the basis of circular cross-section seal of hydraulic booster for MTZ (Minsk Tractor Works) tractors. Materials and Methods. The determination of mobile sealing joints resource is based on the author's methodology, which used ANSYS for realizing a series of accelerated loading cycles that simulates real operating conditions. The developed models consider the processes of wearing, relaxation and hydrodynamic effects acting in a sealing joint. Results. The use of the finite element modeling tools made it possible to determine the change in the stress-strain state of the power steering tightener in MTZ tractors during operation. The mechanism of joint tightness restoration on the basis of self-packing effect is revealed. The comparison of the forms of sections, obtained as a result of numerical and micrometer studies, confirms the effectiveness of the proposed methodology and the adequacy of the results obtained. The analysis of the obtained graphs shows that under normal operating conditions, the life of the sealing joint “cylinder ‒ piston” and “rod ‒ cover” is 2 and 1.12 years respectively, and as the temperature and pressure of the hydraulic fluid increase, decreases exponentially. Conclusions. The results of the study show the high efficiency of the author's methodology. This technique can be used in researches to determine the resource and criteria for the leak-tightness of sealing joints. The graphs of the dependence of the sealing joints life on temperature and hydraulic pressure allow companies, specializing in the creation and repair of hydraulic drives, to develop schedules of preventive measures for their maintenance considering a complex of operational factors. Keywords: seal, O-ring, hydraulic drive, reliability, life, service life, wear, relaxation, ANSYS, finite element analysis Acknowledgements: The study was supported by the Russian Foundation for Basic Research and the Government of the Republic of Mordovia in the framework of the project “Obtaining and research of new composite polymeric materials containing finely dispersed and nanosized modifiers for machine tribo-conjugation elements” (Grant No. 18- 48-130007а_р). For citation: Kuznetsov V. V. The Resource of Movable Sealing Joints with the O-Ring Seal. Vestnik Mordovskogo universiteta = Mordovia University Bulletin. 2018; 28(4):562–582. DOI: https://doi.org/10.15507/0236-2910.028.201804.562-582