| 摘要 |
PURPOSE:To efficiently cool a turbine, by connecting a branch pipe between primary and secondary heaters to both interpose a flow regulting valve to said branch pipe and connect the other end of said branch pipe to a cooling steam pipe opened to a high pressure stage of the turbine. CONSTITUTION:A flow regulating valve 21 connected to a cooling steam pipe of a high pressure turbine 9 is interposed in a branch pipe 22, and the pipe 22 is branched from between a primary heater 13 and secondary heater 14. In this way, high pressure steam at low temperature taken off from the pipe 22 is guided as the cooling steam to a cooling steam pipe 25 while being controlled a flow by the valve 21 on a path of the pipe 22 through temperature of main steam flowig in a main steam pipe 12, then the cooling steam flows in through a nozzle box 26 to directly cool a turbine rotor 27. Further said cooling steam flows in a balance hole 29 formed in a moving blade embedded part 30 to cool said part 30. Accordingly, the cooling steam can be easily obtained without causing the decrease of temperature of steam once heated. |
