Rectification and replacement works including re insulation of defective stator coils of R,Y,B phases including Supervision, erection, commissioning and to attain uniform or satisfactory IR value of 40 MW generator at Kodayar PH- II

Amount

Charges towards de-brazing the end connection jumpers (4Nos.) and bus bars (7 Nos.) with suitable thermal protection.

Charges towards removing connection end and non- connection end insulations and End cap

Charges towards De-soldering of non-connection side (Bottom side) end ferrules with suitable thermal protection

Charges towards De-soldering of connection side (Top side) end ferrules with suitable thermal protection

Charges towards removing of wedges from slot using suitable tools without damaging the coil conductor and core.

Charges towards removing 82 Nos. top bars and 43 bottom bars using special jigs and fixtures without damaging the coil conductor and core.

Charges towards cleaning the entire stator with dry ice blasting, drying out the winding with hot air blower, link the remaining bars with circuit for performing necessary tests to ascertain the healthiness.

HV test on remaining coils in the stator assembly after removing the faulty coils.The test Voltage shall be specified by TANGEDCO.

Rectification of damaged Surge Ring at Connection End side suitably with proper insulation including materials

Charges towards cleaning and polishing the stator core slot for ready to install re-insulated bars.

Charges towards complete re-insulation of top bars at slot portion and overhang portion by using VPI system of insulation and conducting the following tests to ascertain the healthiness. a). IR value measurement at 5KV before and after HV test. b). AC HV test at 23 KV.

Charges towards complete re-insulation of bottom bars at slot portion and overhang portion by using VPI system of insulation and conducting the following tests to ascertain the healthiness. a). IR value measurement at 5KV before and after HV test. b). AC HV test at 23 KV.

Charges towards procurement of the required quantity of glass epoxy class “F” liners, wedges and dying card, mouth block coil overhang support epoxy spacer tape end caps and resin etc., for completing the repair works in good manner.

Site team mobilization, de-mobilization, local conveyance and accommodation charges including To and fro transport charges for transporting the bars from contractor work to Power House using suitable fixtures and vice versa.

Charges towards installing 43 Nos. Bottom bars and 82 Nos. Top bars liners, wedges and end binding the overhang portion with fiber tapes and cards using the binding cement of epoxy resin.

Charges towards soldering both ends of 82 Nos. top bars with respective bottom bars, jumpers using Sn60 soldering material and insulating the brazed overhang portion with class “F” insulation and resin.

Charges towards drying out stator winding and checking the IR & PI values at two hours interval to ascertain the dryness of the stator.

Charges towards conducting the following tests after completion of stator winding. i) IR value at 5 KV before and after HVAC test. ii) AC High voltage test (The test Voltage shall be specified by TANGEDCO) iii) PI value iv) Winding resistance

Charges towards removing 73 nos. connection end and 73 nos. non- connection end insulations and End cap

Charges towards re-soldering of connection side (Top Side) end ferrules with suitable thermal protection including all materials required for re-end termination

Charges towards re- soldering of non-connection side (Bottom side) end ferrules with suitable thermal protection including all materials required for complete re- end termination.

optional If top bar failed during HV test Charges towards removing both side end caps, de-wedging, de-soldering on both sides, removing the bar, re-insulation of top bar slot portion and overhang portion by using VPI system of insulation and conducting the following tests to ascertain the healthiness. a). IR value measurement at 5KV before and after HV test. b). AC HV test at 23 KV. Installation of top bar, re-wedging with new wedges, banding, soldering on both sides including insulating the joints suitably.

optional : If bottom bar failed during HV test Charges towards removing both side end caps, de-wedging, de-soldering on both sides, removing the bar, re-insulation of bottom bar slot portion and overhang portion by using VPI system of insulation and conducting the following tests to ascertain the healthiness. a). IR value measurement at 5KV before and after HV test. b). AC HV test at 23 KV. Installation of top bar, re-wedging with new wedges, banding, soldering on both sides including insulating the joints suitably. Note: For removing the 1 No. bottom bar, pitch portion top bars to be removed for which the item no. 21 is applicable