Block-I in آ‘poor shapeآ’ and needs a آ‘major overhaulآ’

Vol 10, PW 2 (18 May 06) Midstream & Downstream

Ratnagiri Gas and Power also wants to revive Block-I.

As with Block-II and III, this work will be handled by state-owned BHEL, which is expected to start work on 15th June. Shahi was told that Block-I is due for a major overhaul.

Gas turbine spares required for this inspection shall be recommended by the owners engineer and may be procured by Ratnagiri Gas from original equipment manufacturer or supplier. Major items for the steam turbines as per General Electric assessment report shall be recommended by owners engineer.

Shahi heard that the initial inspection reports show that the heat recovery steam generators are in poor shape. However, quantification of spares required at this stage has not been possible.

Shahi was assured that BHEL and General Electric would finalise this quickly. Further, the balance of the plant has run for two years and needs normal overhaul unless we come across surprises.

Ratnagiri Gas said all the hot path components of gas turbine 1A and 1B should be replaced either for completion of the recommended life or for refurbishment as per General Electric technical document GER 3620J. Among the items that need to be refurbished are: moving blade of row 1 and row 3; stationary vane of rows 1, 2 and 3; combustion liners, transition pieces and fuel nozzles.

The items that need replacement are: moving blade row 2. The heat recovery steam generator tube bank needs replacement as well as modification.

All these replacement items are long delivery period items. The old rotor has to be replaced with a modified rotor, as only one modified rotor is available at site.