Эрозионный износ входных кромок рабочих лопаток ЦНД мощной паровой турбины ТЭС. Сопоставление способов упрочнения

The input and output edges of powerful steam turbines last stages working blades of thermal power plants in the process of operation are subjected to considerable erosive wear. Greater erosion experience blades of CHP turbines. The average lifespan of the blades with a length 940 mm (the last stage of turbine T-250/300-23.5 operated in Moscow energy system till replacement does not exceed 55-60 thousand hours at full prescribed life span of the turbine at least 40 years. PAO "Mosenergo" in 2003-2008 compared the effectiveness of three methods for applying functional coatings on the rotor 18 blades of the last stage of turbine T-250/300-23.5 in. The test results of the blades with different coatings were performed using ion implantation, ion-plasma spraying, spark alloying after 5 years of turbine operation testify that the coating could not stand half the turnaround time of the turbine is equal to 6 years, finding the most effective methods to protect the input edges of blades should continue. The introduction of powder laser cladding Stellite-6 on the front edge of the working blades of the last stages of the steam turbine K-200 thermal power plants in Australia had a positive effect and showed the possibility of the operation of welding without razrabatyvanie RND turbine in terms of the TPP. In the stage of practice is an experienced domestic technology laser cladding of Stellite powder brand В3К on the front edge of the blades of the last stage of the turbine K-300. Tests on samples showed an increase in the resistance welding in comparison with the resistance soldering of the plates.