Sayano-Shushenskaya Hydroelectric Power Station Accident
2.0 Root Factors
On August 17th, 2009, the Sayana-Shushenskaya powerplant suffered a massive accident that resulted in the flooding of the engine and turbine rooms and two electric generators to explode underwater due to short circuit. Due to fatigue caused by extensive vibrations, the pins holding turbine number 2 breaks apart. Water rushing down the penstocks forces the 1500 ton turbine through the powerhouse floor launching it 50 feet into the air. A fountain of water flowing at 67,600 gallons per second destroys the roof and floods the turbine hall causing power failures and short circuit to turbines 7 and 9[6].
4.1 Design & Process Factors
Shortly after its installation, turbine number 2 had been experiencing problems due to defects in seals and shaft vibrations. In March 2000, a complete overhaul on turbine 2 was performed where cavities of 12 mm in depth and cracks up to 130mm in length found and repaired. Despite these efforts, turbine number 2 continued to have problems resulting in further repairs in 2005 and 2009[7][5].
Prior to the accident, the turbine was undergoing scheduled maintenance from January through March 2009. During the maintenance period, the turbine blades were welded due to appearance of cracks and cavities caused by long period of operation. The turbine was also equipped with a new electro hydraulic speed regulator supplied by Promavtomatika company [7].It was resynchronized to the grid on March 16 although the vibrations remained high but did not exceed specifications. The vibrations increased between April and July exceeding the specifications causing the unit to be taken offline until August 16th when the Bratsk fire forced managers to push the turbine into service again. LMZ, the St. Petersburg metalworks that manufactured the turbines gave it a 30 year service lifespan. Turbine 2’s age on August 17th was 29 years 10 months [6].
Turbine 2 was started and switched to regulating mode due to the Bratsk fire. Data on
On August 17th, 2009, the Sayana-Shushenskaya powerplant suffered a massive accident that resulted in the flooding of the engine and turbine rooms and two electric generators to explode underwater due to short circuit. Due to fatigue caused by extensive vibrations, the pins holding turbine number 2 breaks apart. Water rushing down the penstocks forces the 1500 ton turbine through the powerhouse floor launching it 50 feet into the air. A fountain of water flowing at 67,600 gallons per second destroys the roof and floods the turbine hall causing power failures and short circuit to turbines 7 and 9[6].
4.1 Design & Process Factors
Shortly after its installation, turbine number 2 had been experiencing problems due to defects in seals and shaft vibrations. In March 2000, a complete overhaul on turbine 2 was performed where cavities of 12 mm in depth and cracks up to 130mm in length found and repaired. Despite these efforts, turbine number 2 continued to have problems resulting in further repairs in 2005 and 2009[7][5].
Prior to the accident, the turbine was undergoing scheduled maintenance from January through March 2009. During the maintenance period, the turbine blades were welded due to appearance of cracks and cavities caused by long period of operation. The turbine was also equipped with a new electro hydraulic speed regulator supplied by Promavtomatika company [7].It was resynchronized to the grid on March 16 although the vibrations remained high but did not exceed specifications. The vibrations increased between April and July exceeding the specifications causing the unit to be taken offline until August 16th when the Bratsk fire forced managers to push the turbine into service again. LMZ, the St. Petersburg metalworks that manufactured the turbines gave it a 30 year service lifespan. Turbine 2’s age on August 17th was 29 years 10 months [6].
Turbine 2 was started and switched to regulating mode due to the Bratsk fire. Data on