500MW Generator

500MW GeneratorInitial IsolationGenerator Circuit Breaker outUAT A n B Breaker Racked outField Excitaion fuses to be removed by Testing LabTurbine on BarringIsolation

Blower IsolationEmergency actuatorExciter Flap Gates ActuatorTube LightsStroboscopeEarth fault BrushesStroboscope LightsConnections RemovalPMG Rotor Outgoing cableD.C Supply of Main exciterD.C Earth fault Connections removalQuardature axis Connections

Important PointsGenerator will move by 27mm when it runsCRO Coupled run out to be taken.It is measured by setting dial guage at 50 and will see the deviation at each bolt if the minimum is 48mm then it is less by 0.02mmAfter decoupling with the help of Loose coupling bolts alignment readings of generator rotor coupling and LP coupling to be checked.Radial readings will be taken with the help of clamp tighten on master coupling of LP coupling and checked on Turbine couplingAxial clearance here is checked by Slip guage by setting at 0 and noting the difference of which side generator is

Swing checkThe top half of Bearing no 7 is removed Now shaft of bearing no 7 is taken on load by sling by keeping copper plate and by rotating the shaft readings will be taken on Exciter side coupling

Exciter Coupling and Generator Coupling Run outWith decoupled LP coupling by rotating the shaft run out is takenRemoval of Exciter RotorBy removing bearing no 7 bottom half and taking load on sling and resting the exciter load on resting device and with the help of jacking bolts we will separate the generator and exciter rotor and with the help of guiding pins after jacking by removing CC bolts in between exciter n Generator coupling Exciter rotor will be removedSeal body removalAfter removing top half bearing Seal body is loosened by taking the load on lifting device the exciter side bottom half is removed then seal body is moved to front and after giving rest on the bottom half the top half is dismantled and removed with the help of jugad.Then the top seal ring is removed by dismantling the half portion after that the top half is moved up and removed and then seal ring bottom half is removed and then again bearing is placed and the lifting device load is removed.While lifting lift it by max 0.2mmSeal body Lifting DevicesExciter side lifting device is having large OD than Turbine side lifting device because the lifting device will be placed on coupling in exciter side and on shaft towards turbineTwo stoppers will be used they are used for both locking the rotor and also for moving axiallyInner oil catcherThe bolts will be fixed from outer sidei.e seal body End shield and inner oil catcher.there will be oil deflectors also.Bottom End shield Downing First load will be taken on sling and then bearing is removed then Teflon piece is placed on the rotor bottom and sling is removed then sling will be taken on hooks and bottom end shield is removedThen again load is taken on sling and piece is removed and sliding plate on top of it and again piece is placed and load is taken off. Repeat the procedure on turbine side also.

Exciter side top endshield

Exciter side end shield Bolting system

Exciter side CC bolt Housing retaining rings and bottom end shield

Exciter side Bottom End Shield

Coolers Holes

Jacking Bolts and seal body Removal Hooks

Turbine side Top End Shield Lifting Device

Exciter side H2 Coolers and bottom End Shield

Compressor Baffle Rings

Compressor Movinf Blades

Compressor Blades

Axial Clearances

Seal body Lifting Device

Lp and Generator alignment Clamp

Lifitng Device of Bearing and Compressor Moving Blades(B and C marking done on holes)

Lifitng of Compressor moving Blades

Lifitnf Device arrangement

Rotating of Top Right Moving Blades to centre for Removal

Rotating of Moving Blades

Jugad for Rotating Bottom Half of Compressor Moving Blades

Lifting Device Arrangement and its placement towards turbine side

Rotating Jugad with the help of loose bolt because while shifting bottom half to top it will rotate fastly and cannot be stopped at top

Rotating of Rotor very much Precisely with the help of Loose bolts

Compressor Gaskets1mm gaskets is placed at first and last moving blades to move top Left o,right or bottom blades.while moving with the help of thread it will scratch the rotor so we will place the gaskets.If we place at first n last automically other three will rise.For shifting bottom to top gasket is needed for placing near the bottom of Jugad.they kept 3mm water sheet16mm bolts are needed for lifting the moving blades segmentFor Axially moving of the blades there are check nuts we can adjust them by tightening it will hit the end shield and come backThese moving bolts are tightened to end shield with bolts passing through these check nuts and argon welding will be done latterFor checking radial clearance of Fixed plates a thickness piece plate is given by keeping instrument we can check it.These plates are given by leaving one moving plate set i.e top left ,right and bottom it will be availableExciter rotor pressure test with N2 done at 5.8kscMain rotor pressure test done with n2 at 6Ksc for 6 hoursWater Winding Connection

Generator Schedule

Exciter Side Box Connection

Turbine Side Box Connection

Winding Connection

Water Hose Pipe Connection

Generator rotor shoe Blocks

Gen rotor Racking out Device

When rotor is threaded out it is kept on wooden block for adjusting its height it is used

Compressor blades hub covering.While racking out it must not touch the stator

Skit Plate for racking out the rotor

Downing the exciter side bottom end shield

Tying rope for Skit plate

For removing seal body bottom

Compressor moving blades removal Jugad

Placing the skit shoe

Skit shoe

Pressurisation Jugad for Exciter n main rotor

Small and Large blocks used for Raising device

Pedestal of rotor placed in between both beams

For keeping on rotor while lifting with sling

For Drawing out rotor

Jugad placed on exciter side main rotor

Downing turbine side Bottom End shield

Jugad on turbine side rotor for skitting

Shoe placed at the bottom of rotor

Taking one side of rotor on wooden Blocks

Taking load on slings

Air gap measurement Device

Bearing no 6 Stoppers

Bottom Pedestal

Wedge Tightness Test