Potapov D. Extension of service life of rails by system grinding on-stream.

Object of research are rails and their work in a way. The purpose - prolongation of service life of rails due to system engineering carrying out of grinding works with use railgrindig trains with active working bodies on railways of Ukraine. Methods of research - for development of mathematical model of work of rails in a way for different operational conditions are used methods of the theory of reliability, the theory of destruction, mathematical statistics. The basic theoretical results - are modified mathematical models of work of rails in a way at their damage by defects of a контактно-fatigue origin; analytical expressions of change of hardness of metal in the head of rails on depth are received depending on the missed tonnage, a kind of thermal processing. The basic practical results - the normative base for planning and carrying out of grinding of rails railgrinding trains with active working bodies for railways of Ukraine is developed; service life of rails are determined in view of operationalfeatures of underground. A degree of introduction - results of researches are used by development of the following normative documents: "Technical instructions on operation of rails and elements crossing translations of the Kiev underground", "Technical instructions on operation of rails and elements стрелочных translations of the Kharkov underground", "Regulations about to complex system of grinding of rails in railway track"