| 摘要 |
PURPOSE:To improve reliability, by determining a relation between spill over reference secondary pressure and casing pressure through an electric adjusting meter so as to open or close a spill over valve when actual reheat pressure accords with preset reheat pressure. CONSTITUTION:A signal for obtaining determined spill over reference secondary oil pressure P5 is input from an electric adjusting meter 25 in the form of voltage to an electric oil-pressure converter 26, and the voltage is converted into the pressure P5 and transmitted to one of the bellows chambers of a comparator pressure controller 20. Because casing pressure P6 is low in a low loaded range of turbine output, preset secondary oil pressure P1 becomes higher than the pressure P5, only the pressure P1 is transmitted to the controller 20. If the pressure P6 increases, the pressure P5 becomes higher than the pressure P1, and only the pressure P5 is transmitted to the controller 20. When reheat pressure by the pressure P5 is larger than the actual reheat pressure P3 of the bellows chamber, a spill over valve 17 is closed while opened in a reverse case. |
