| 摘要 |
PURPOSE:To prevent generation of thermal stress and thermal deformation during cooling by connecting the exhaust pipes of a high and an intermediate pressure turbines to the respective exit ports of a main steam stop valve and a combined reheating valve and connecting these exhaust pipes to a vacuum pump, thus installing an exhaust system of cooling air onto the turbine system. CONSTITUTION:When the preparation for cooling is completed, and interlock is released, and a vacuum pump 12 is started, a controlling unit 55 operates and the stop valves 22-24 in an exhaust system opens the outside air is absorbed by a vacuum breaker 17. A portion of the outside air absorbed into a condenser 11 flows into from the exhaust side of a low-pressure turbine 10 and cools metallic part, and is discharged into an exhaust pipe 19. While, the outside air which flows into a ventilator valve 13 side flows into the exhaust side of a high- pressure turbine 4 and cools it, and is discharged into an exhaust pipe 18. The outside air exhausted into these exhaust pipes 18 and 19 is introduced into a cooler 21 for cooling through an exhaust pipe 20, and discharged into the atmosphere by a vacuum pump 12. |
