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It has been confirmed for almost all elements of the condensate-feed channel of pipe setups in nuclear and heat and power plants are subjected to erosion-corrosion wear. Other forms of wear of a metal in most cases occur simultaneously with this process. Erosion-corrosion wear of a metal is observed to a large degree in pipes operating at 160-200~ i.e., high-pressure heaters, steam pipes from a high-pressure heater, bypass pipes in high-and low-pressure heaters, and pipes for transporting the condensate of the warming steam [1].In [1, 2] it is pointed out that analysis of the experimental results and observational data for zones subjected to the greatest damage to metal in the power equipment suggests that with time erosion-corrosion weak should be expected in high-power saturated-steam pipe lines (I000 MW), primarily at locations where the temperature and moisture content of the steam correspond to the greatest intensity of wear (160-200~ > 6%). This makes it important to study the laws of erosion-corrosion wear of a metal. However, many questions are far from a solution. In the USA alone the annual losses as a result of erosion and corrosion amount to several billions of dollars [I]. On the one hand, this situation is explained by the fact that the intensity of wear depends on many factors (chemical composition of the metal and the working medium, hydrodynamics of the flow, constructional features of the heat-exchange equipment, and others), and for many cases no systems analysis of the combined effect of these factors has been performed. On the other hand, the development of studies of the wear and the development of measures for reducing wear are strongly impeded by the lack of a data bank on the damage vulnerability of the metal of elements in the power-generating units [1, 2].Our objective in the present paper is to analyze the character of the erosion-corrosion wear of the entrance sections of the coils of the high-pressure heaters with a carbon steel pipe panel in the power-generating units of nuclear power plants with K-1000-60/1500-2 turbines. The history of the problem is as follows. The use of an apparatus with a highpressure heater and a pipe panel made of carbon steel started abroad at the beginning of the 1960s. This concerned powergenerating units operating at supercritical pressure, where the use of copper alloys led to the formation of copper oxide deposits in the turbines. For power-generating units operating at subcritical pressure the choice of carbon steel for the coils was dictated by economic considerations [3]. Operating experience showed that in the case of power-generating units operating at super-and subcritical pressures the high-pressure heaters with carbon steel pipe panel are the source of the high content of iron oxide in the feedwater and are subjected to intense erosion-corrosion wear. A complex of investigations performed in the 1960s solved the problem of intense wear of the entrance sections of the pipes for the foreign-made chamber high-pressure heaters by combined applic...

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