RESEARCH OF WEAR OF PLUNGERS AND BUSHINGS OF THE FUEL PUMP OF THE DIESEL ENGINE

Compliance with the requirements of the new international standards for diesel fuel (for example, reduction of sulfur compound content) poses a new problem: the lubricating properties of the fuel deteriorate. The experience of the use of highly purified fuels in a number of countries of Western Europe and the United States showed that the reduction of harmful substances in the exhaust gases is accompanied by premature failure of precision pairs of fuel equipment, including plunger pairs of high-pressure fuel pumps, as a result of power losses, increased fuel consumption, increased fluidity of exhaust gases. To solve the problem of wear of the structural pair "plunger-bushing" in this work, the problem of studying the physical and mechanical process of wear of their contacting surfaces from the standpoint of fatigue wear theory is set and solved. The stochastic nature of the destruction of micro-volumes occurring on the contacting surfaces of the plunger pair in the micro-and macro-levels, the influence of temperature gradients make it difficult to obtain a complete mathematical description of the main processes affecting the mechanism and the intensity of their wear. The absence of equations that reflect the relationship of all factors affecting the wear process, it is advisable to use the analysis of the dimension of the physical quantities characterizing the friction and wear of parts for the modeling process. The empirical experience of the science of friction and wear allows us to imagine the influence of certain factors on the process under study. Due to the lack of the possibility of mathematical description of the influence of all factors on the process of wear of the plunger pair, the method of the theory of analysis of dimensions is used. As a result, the criterion relations are obtained, allowing judging the qualitative relationship of the parameters of the acting factors.