| 摘要 |
PROBLEM TO BE SOLVED: To suppress the occurrence of a thermal unbalance to a rotor through prevention of inflow of wet steam and to prevent the generation of rotor vibration. SOLUTION: A number of balance holes 75 are peripherally formed in the rotor disc 79 of the final stage moving blade 74 of a steam turbine. A flow guide 77 from an exhaust chamber from which steam flows out is supported at a support member 80, and a gland part 81 is mounted on the lower end of the support member 80. A cavity 78 consists of the support member 80, a blow guide end, and the disc 79. Wet steam penetrates through an opening part 82, a drain flows in a rotor 73 to locally cool the rotor, and temperature distribution of the rotor is rendered uneven. However, an L-shaped and semicircular steam inflow preventing plate 1 is mounted, penetration of steam and drain are prevented from occurring to the rotor part, a thermal unbalance of the rotor is prevented from occurring, and vibration due to the thermal unbalance is prevented from occurring. |
