| 摘要 |
PURPOSE:To prevent steam from flowing outside through a valve rod when said rod slides within a bush by providing a shaft seal packing on a bush which guides sliding of said rod. CONSTITUTION:A steam control valve is equipped with a main valve 22, a valve body 22a of which is slidably guided in a sleeve 24 housed in a valve casing 20, and also with an auxiliary valve 23 housed in the main valve 22. A valve rod 27 arranged in linkage with a valve body 23a of the auxiliary valve 23 is guided to slide by means of a bush 28 accommodated in a stand 25. A balance chamber 30 is formed through demarcation by a valve body 22a of the main valve 22, sleeve 24, valve rod 27, stand and the like. In this case, the second bush 31 is detachably screwed on the bottom of the bush 28. On the other hand, the bush 31 is provided with a labyrinth packing 32 as a shaft seal packing, and each fin 34 of said bush is placed in opposition to the outer peripheral face of the valve rod 27 through a gap G. |
