Three units of Bhakra power project shut down

05 March, 2013

Bhakra Beas Management Board (BBMB) has been forced to close third unit of Bhakra left bank powerhouse due to turbine faults. The unit is under forced shut down following breakage of inner head cover liner of the turbine. Officially, the unit has been taken out for 90 days to carry out annual maintenance. Units two and five of left bank are already under shutdown due to delayed renovation and modernization works.

According to sources, inner head cover liner of turbine was found detached from its original position following shearing of all the fixing bolts on February 19 this year. The vibrations are only checked manually. There is no record of vibrations at the time of shearing of bolts as it is based on manual experience of staff. It may be mentioned that there is no way to record on line vibration as no such monitoring system has been installed.

A senior BBMB official said that to carry out the repair works it will take more than three months. The dismantlement and reassembly of unit for repair of the turbine inner head cover liner is a huge work.

Last year in May, 10 bolts were found sheared and were replaced by new ones. Again, during annual maintenance in November last year six bolts, which were replaced in previous maintenance, were found sheared and again replaced.

According to sources, bolts made of normal mild steel were manufactured at Nangal workshop and used last year which have again led to shearing of bolts. The original bolts were made of carbon steel. This time suitable quality of bolts of carbon steel as were recommended by Hitachi shall be manufactured and used to avoid future breakdowns, said a senior official.

The commissioning schedules of Bhakra Left Bank Power House Units 2 and 5 have repeatedly slipped .The units are under shutdown for Renovation, Modernization(R&M) and Upgrading and the works were supposed to be completed in 12 months from date of start of work.

The R&M of Bhakra left bank units has been delayed by more than two years and units may not be commissioned within three years against stipulated period of one year. These units are also likely to be commissioned in next three months.

R&M works of unit 4, 3 and 1 will be taken in a phased manner after the completion of ongoing work of unit 2 and 5.