MAJOR OVERHAUL OF TURBINE AND GENERATOR FOR UNIT A3
Steam Turbine specifications:
Output – power 200 MW
Manufacturer LMZ-Russia
Type K-200-130-1 Condensate
With three Cylinders HP, IP, and LP Cylinders
With fresh and reheated steam
Commissioning year 1970
Works included on Turbine:
Dismantling of outer cover of HP and IP Cylinders, thermal insulation according to instructions of manufacturer, cross over pipes, all bearing housings and perform all necessary associated measurement, upper part of journal bearings, rotors couplings and perform all necessary measurement, turbine HP, IP and LP cylinders, main oil pump including turbine governing system, stop valves, protection valves and governing valves of HP and IP Cylinders.
Cleaning of integral oil piping system of lube oil control, generator oil system, adjustments and sealing system of generator tank including oil turbo-coolers 1, 2, 3 as well as sealing oil tank of the Generator, sumps and definitive close-up of bearings of turbine and generator.
Measurement of positions and air clearances, rotor-stator displacement and comparison with the values of 2012/2013 overhaul, steam flow part (including eccentricity measurement of rotors) after dismantling, deformations of turbine diaphragms, thermal clearances of diaphragm between rings, diaphragms and turbine casing, self vibrations of rotor blades of stage 27 and 31 of the LP rotor, lower parts of turbine after dismantling of upper parts, balance weight of HP, IP turbine supports after dismantling of upper part, vertical and horizontal dilatation components of turbine (thermal ventilation), journal bearings prepared preliminary with new white metal TEGO 738 as well as achieving the final dimensions, radial and axial rotor positions after definitive alignment of rotors line, vibrations during the start-up with different regimes (with and without load) taking into account also the measurement of phases, amplitudes and frequencies.
Non-Destructive Testing of Cylinders/Casing inside and outside, seizing pipe from steam turbine number 2,3,4,5,6 and 7, including return dumpers up to damper valve of the receivers, rotors, nozzles of HP and IP Casings, diaphragms, rings of diaphragms, bolts, stop valves, protection valves, governing valves U-pipes from protection valves of IP casings up to governing valves, U-pipes from protection valves (repair bearings) of HP, IP and LP Cylinders.
Repair of cylinders and rotors of HP, IP and LP, main oil pump including turbine governing system, stop valves, protection valves and governing valves of HP and IP Cylinders, balance weight of HP, IP turbine supports after dismantling of upper part, vertical and horizontal dilatation components of turbine (thermal ventilation), cracks in turbine casings based on NDT results, turning gear, explosion dampers of LP Cylinder, journal bearings prepared preliminary with new white metal TEGO 738 as well as achieving the final dimensions, heating system of flanges and bolts in HP Casing and IP Casing (valves, safety valves, pipes, collectors and measurements instruments, according to the control results should be replaced, lubrication pumps, start-up pump of the turbine.
Assembling of thermal insulation according to instructions of manufacturer, oil sealing, integral oil piping system of lube oil control, generator oil system, adjustments and sealing system of generator tank including oil turbo-coolers 1, 2, 3 as well as sealing oil tank of the Generator, three new oil coolers, start-up pump of the turbine.
Commissioning of integral oil piping system of lube oil control, generator oil system, adjustments and sealing system of generator tank including oil turbo-coolers 1, 2, 3 as well as sealing oil tank of the Generator, lubrication pumps, the start-up pump of the turbine.
Generator:
Manufacturer ELEKTROTYAZMAS Harkov – Ukraina
Output 200 MW
Type TGV-200, 15750V, 3000rpm, 50Hz, 3 phase
Year of start-up: 1971
Works included on Stator:
Visual control of all electrical and mechanical elements, and their reparation
Electrical examination of the Stator (before and after Overhaul)
Investigation and detailed mechanical and electrical repair of zero and phase insulators of Generator
Painting of stator winding’s
Dismantling, control, repair of bearings, sealing in the side of bearing no. 6 and no. 7 as needed for filling with white material
Works included on Rotor:
Visual inspection of all electrical and mechanical components of the rotor after dismantling.
Measurement of rotor eccentricity before and after processing-ratification taking into account also hats re-tightening rings.
Ratification of damaged rotor surfaces and Non-Destructive Testing
Ratification of collector rings.
Controlling a rotor cooling channels
Control and repair wrap connections (flexible slopes) with the brush collector rings.
Checking the connection of the contact bolts seal (current conduction).
Replacement of brushes and damaged brush holders and their calibration
Delivery and replacement of the clutch tubes of the brush holder
Repair the seal of lodge – brush holder and coloring
Dynamic balancing after rotor repair.
Delivery, installation of new metering circuits in the generator for the measurement of the temperature (iron, copper) and the sending of all these measurements in the command with the new instrument.
Detail seal of the generator including all metering exits and all exits of insulators and mechanical parts.