PROBLEM TO BE SOLVED: To reduce damage of a connecting pipe by respectively providing an inlet and an outlet of a primary reheater with connecting pipes and interposing a steam flow control valve in the connecting pipes in a reheat steam system wherein reheat steam is made to flow into two flow reheat steam lines and heated by a first and second reheaters in the respective reheat steam lines before being fed to a turbine again. ;SOLUTION: When a control valve 10 in a left reheat steam line is opened, steam flow in the left line increases by an amount corresponding to a capacity of the connecting pipe 9, reducing loss of pressure so that steam flow through the left reheat steam line becomes greater than that through a right reheat steam line in a reheat steam flow piping 5. On the other hand, since the overall amount of the reheat steam through a connecting pipe inlet 1 of a steam reheater is constant, steam flow through the right reheat steam line is reduced. If amounts of heat absorbed by a primary reheater 2 and a secondary reheater 4 are constant, temperature of the reheat steam in the left reheat steam line is lowered by an amount corresponding to the increase of the reheat steam flow and temperature of the reheat steam in the right reheat steam line is raised by an amount corresponding to the reduction of the reheat steam flow. Thus, cooling water through a steam reheater desuperheater control valve 8 is not used, or even if the cooling water is used, the amount of the cooling water can be reduced. Damages of the connecting pipes, therefor, can be reduced.;COPYRIGHT: (C)1997,JPO
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