Abstract: A steam turbine plant comprising: (a) first, second and third turbines which are coaxially combined with each other; (b) a boiler for supplying high pressure steam to the first turbine; (c) first, second and third bypass means for selectively bypassing steam around the first, second and third turbines, respectively, wherein each of the bypass means comprises means for cooling the steam; (d) a condenser for condensing steam discharged from the third turbine; (e) means for forming a vacuum in the condenser; (f) a first reheater for reheating steam discharged from the first turbine and out of the first bypass means and supplying the steam to the second turbine; (g) a second reheater for reheating steam discharged from the second turbine and from the second bypass means and for supplying the steam to the third turbine; (h) first, second and third control valves for controlling steam flow rates flowing into the first, second and third turbines, respectively; (i) first, second and third bypass valves for controllin

Abstract: A steam turbine comprises a casing; turbine vanes rotatably set in the casing; a plurality of partition walls which extend along radial directions from the rotation center of the turbine vanes to define a plurality of steam valve chambers in the casing; steam supply pipes respectively connected to the corresponding steam valve chambers; and regulating valves which are fitted to the respective steam supply pipes to regulate respectively the flow rate of steam streams supplied to the respective steam valve chambers. At least one partition wall for dividing the interior space of the steam turbine into adjacent steam valve chambers is provided with at least one penetrating hole for causing the steam valve chambers to communicate with each other.