NCTPS I SE MI circle Turbine Maintenance Division Annual Overhaul work for the year 26 27 Specification No 114 26 27

Disassembly from its position & Reassembly in position of Pedestal cover no-2: This work involves - Checking and recording the TOC & SOC readings of oil guard ring clearance, Removal of the all top cover bolts, Lifting of Turbine bearing Pedestal Top covers to turbine floor, cleaning the Pedestal cover with diesel and air, reassembly of top cover to its position, tightening of the all top cover bolts, Checking and recording the TOC & SOC readings of oil guard ring clearance. Including the cost of consumables and hire charges for T&P’s.

Disassembly of Oil Guards Assembly in Bearing No-2 by removing all bolts, lifting the top and bottom portions of the assembly using lifting devices, transferring the components to the turbine floor, and thoroughly cleaning them with diesel and air. Charges include consumables and T&P’s.

Disassembly of Yoke Assembly in Bearing No-2 by checking and recording interference and clearance readings, loosening and removing parting plane bolts and cylindrical pins, releasing the adjusting rings, and lifting the top and bottom portion assemblies to the turbine floor for thorough cleaning with diesel and air. Charges include consumables and T&P’s.

Disassembly of Thrust Bearing Assembly in Bearing No-2 by measuring and recording shaft dimensions, dismantling the top and bottom assemblies using lifting devices, transferring components to the turbine floor, and dismantling & cleaning of active and non-active tilting pads, upper and lower levelling rings, and lube oil lines. Charges include consumables and T&P’s.

Inspection of Thrust bearing assembly Active Pad and Non active Pad- assembly of Upper part & Lower part and 28 nos of pads) in Bearing no-2 by Conducting Dye Penetrant Test. Including the cost of consumables and hire charges for T&P’s.

Inspection of Thrust bearing assembly Active Pad and Non active Pad - assembly of Upper part & Lower part and 28 nos of pads) in Bearing no-2 by Conducting Ultrasonic Test. Including the cost of consumables and hire charges for T&P’s.

Disassembly of Axial Key and Radial Key in Bearing No-2/by measuring pre-disassembly clearances, extracting the keys from the rotor and bearing positions, transferring the components to the turbine floor, and thoroughly cleaning and taking final dimensions of the keys. Charges include consumables and T&P’s.

Rectification, Correction, and Centering of Main Turbine Rotor Axial Float by fixing the fixture arrangement on the pedestal no-2 parting plane, mounting dial gauges, and using a special toolkit to shift the rotor between the generator and turbine sides. The work includes measuring and recording total axial float from the extreme ends of the active and non-active pads, comparing readings with specifications, and positioning the rotor precisely at mid-float. Charges include consumable and T&P’s.

Reassembly and Replacement of Axial and Radial Keys with Required Corrections as per Drawing by preparing and adding precision shims to the axial keys to restrict rotor movement, and installing the fitted keys to position and secure the Main Turbine Rotor precisely at mid-float. The scope includes verifying alignments against technical drawings and recording all final clearance measurements. Charges include consumables and T&P’s.

Reassembly of Thrust Bearing Assembly in Bearing No-2 by thoroughly cleaning all components with diesel, checking the blue contact matching of the 28 nos. of active and non-active tilting pads on a surface plate, performing necessary scraping and fine finishing for sufficient impression marks, and structurally servicing or replacing thrust pads as required (Thrust pads to be supplied by TNGCL). The scope includes cleaning the bearing housing and lube oil lines, reassembling the upper and lower halves, lifting the assembly into pedestal no-2, tightening all bolts, and recording final technical measurements. Charges include consumables and T&P’s.