Donbasenergo reports that the reason why the vibration of the turbine of Power Unit 7 at Sloviansk TPP increased on January 17 this year was the breakage of a fragment of the blade lock packet of working blades No. 11 of the high pressure cylinder (HPC) caused by erosion and abrasive wear of the blades in the area where they intersect with the bandage flange, since this area has a voltage concentrator.
Within the period of repair works it is planned to replace the high pressure rotor with a backup one, to replace the nozzle apparatus and diaphragms No. 2-8, to repair the cylinder upon the fault finding results.
Now the high-pressure cylinder of the turbine of Power Unit 7 has been opened, and the rotor, inner casing and flow part (diaphragm shells) have been dismantled. Based on the fault finding done for this equipment, a final repair schedule will be developed.
The plant also continues to align the backup high-pressure turbine rotor of the power unit, clean up for the fault finding activities and metal inspection of HPC casings. Once the fault finding is complete, the horizontal connectors of the outer and inner housings will be ground and fitted and then the inner housing of the HPC will be factory-fitted for installation of a new nozzle apparatus.
As a socially conscious enterprise, after the emergency shutdown of Power Unit 7, Donbasenergo had to turn on Sloviansk TPP first-phase boilers that run on a coal-gas mixture. They allow to keep the dwellings of Mykolaivka, a town of power engineers, warm, which brings additional losses to the company.