| 摘要 |
PURPOSE:To prevent a casing from vibrating due to its thermal deformation, by making larger the radius to the inner surface of at least one of an upper and a lower packings for regions containing a vertical axis extending on the center of a rotary shaft, than that to the inner surfaces of other adjacent packings. CONSTITUTION:The radius R2 to the inner surface of at least one of an upper and a lower packings 121, 124 containing a vertical axis extending on the center 0 of a rotary shaft 11 is made larger than that R1 to the inner surfaces of other packings 122, 123, 125, 126 to make larger the vertical gap between the rotary shaft and the packing unit 12 than the horizontal gap between them to prevent a turbine casing from vibrating due to its forward or backward stoop deformation. Since the increase in the cross-sectional area of the sealed gap between the rotary shaft 11 and the packing unit 12 is minimized, the leak of a fluid through the sealed gap is reduced to suppress the loss of energy to prevent the efficiency of a turbine from falling. The packing unit 12 is easy to process and its production cost is low. |
