| 摘要 |
PROBLEM TO BE SOLVED: To facilitate painting and repairs inside a volute casing without reducing efficiency in a large hydraulic machine.SOLUTION: A volute pump 20 comprises: a rotating shaft 11; a centrifugal impeller 8 attached to an end of the rotating shaft; a diffuser 5 arranged on the outer diameter side of the centrifugal impeller and including a plurality of blades arranged at intervals in a circumferential direction; and a volute casing 1 arranged on the outer diameter side of the diffuser. The volute casing comprises: a volute part in which its cross-sectional area is gradually changed in a circumferential direction; and two ring members 3a and 3b formed at an opening part on the inner diameter side of the volute part and arranged in parallel. The diameter of inner diameter ends of the ring members is equal to or larger than the diameter of outer diameter ends of the blades of the diffuser. |
