THE EFFECT OF DAMAGE RATE OF TECHNOLOGICAL SUBSYSTEMS EQUIPMENT ON FUNCTIONAL FAILURES OF STEAM TURBINES

Abstract

The article presents the results of research on the eff ect of damage rate of steam turbine technological subsystems equipment on the operation of a power plant. It was revealed on the basis of analysis of reliability indicators of power units that malfunctions of steam turbine unit (STU) equipment accounted for 25 – 30 % of the total number of failures. The article presents the results of the malfunction analysis for the equipment of various STU technological subsystems operating in the power units and at cross-links power stations and leading to the turbine unit shutdown (failure). It is shown that critical equipment causing turbine unit shutdown in 70 or more percent of cases is represented by the equipment of three technological subsystems: condenser unit, oil supply subsystem and feed water subsystem. Based on the analysis results for operational documentation obtained at the Ural-Siberian region power plants for more than 300 power units with capacity of 200 to 800 MW, the article presents data on the eff ect of equipment failures at various technological subsystems on unplanned shutdowns of steam turbines. It also studies the basic malfunctions of the most critical equipment (that is of condenser, ejector, gland steam heaters, feedwater and condensate pumps, oil coolers, etc.) which can result both in its failure and in turbine unit functional shutdown. Statistical data is presented on the distribution of the causes of damage to condensers, ejectors, feedwater and condensate pumps and oil system equipment. Data presented in the article can be used to develop modules of technical condition monitoring and diagnostics as well as failure preventing measures for steam turbine technological subsystems equipment.