DUSHANBE, June 16, 2014, Asia-Plus -- Specialists from Ukraine’s Open Joint-Stock Company (OJSK) Turboatom have changed hydraulic lock of Unit 3 at the Norak hydroelectric power plant (HPP).

According to information posted on Turboatom’s website, on operation on changing the ball hydraulic lock was finished last month.

Turboatom’s chief designer for hydraulic locks, Alexander Linnik, noted that it had been a unique operation because it had been carried out at the hydropower plant.  Simultaneously, the rotor wheel was also changed.  Repair operations reportedly lasted for six month.

Turboatom specializes in the production of turbines for thermoelectric and nuclear power stations, hydraulic turbines for hydroelectric power stations and hydro-accumulator stations, gas turbines for thermoelectric power stations, and steam-and-gas equipment as well as other energy equipment.  A 75.22% stake in the enterprise belongs to the state and is managed by the State Property Fund.

The Norak Dam is an earth fill embankment dam on the Vakhsh River.  At 300 meters it is currently the tallest dam in the world.  Construction of the dam began in 1961 and was completed in 1979, when Tajikistan was still a republic within the Soviet Union.  The Norak Dam is uniquely constructed, with a central core of cement forming an impermeable barrier within a 300 meter-high rock and earth fill construction.  The volume of the mound is 54 million m³.  The dam includes nine hydroelectric generating units, the first commissioned in 1972 and the last in 1979.

A total of nine hydroelectric turbines are installed in the Norak Dam.  Originally having a generating capacity of 300 megawatts each (2,700 megawatts total), they have since been redesigned and retrofitted such that they now combine to produce 3,000 megawatts.  Units 1,2,3,4,6,7,8, and 9 now have capacity of 335 megawatts each and Unit 5 now has capacity of 320 megawatts.