| 摘要 |
PROBLEM TO BE SOLVED: To prevent radiant heat from a valve casing of a steam valve and a valve rod and heat of leaked steam from being transmitted to a valve driving device, and to provide the deformation of the valve rod.SOLUTION: In a steam valve 10, a steam prevention valve 11 and a steam control valve 12 are installed in the side of the inlet of a steam turbine, and a hydraulically-actuated valve driving device for driving a valve body 16 of the steam prevention valve 11 and the steam control valve 12 via a valve rod 23 is provided. The steam valve 10 is configured to have a heat shield structure in which a valve coupling 35 connecting the valve driving device 24 and the valve rod 23 having a heat shield plate 40 is provided so that the heat shield plate 40 prevents heat from being radiated from the valve casing 13 and the valve rod 23 to the driving device 24. |
