| 摘要 |
PCT No. PCT/NO97/00036 Sec. 371 Date Aug. 6, 1998 Sec. 102(e) Date Aug. 6, 1998 PCT Filed Feb. 6, 1997 PCT Pub. No. WO97/29286 PCT Pub. Date Aug. 14, 1997The invention relates to a centrifugal pump device, comprising a pump casing (1) having an inlet (2) and an outlet (3), an impeller device inside the casing (1) having one or more pump stages (5-7) with a common rotary shaft (4), and a non-return valve (8) between inlet (2) and outlet (3). The device is characterized in that the non-return valve (8) is provided on the discharge side of at least a first pump stage (5). |
