| 摘要 |
The proposed centrifugal pump for pumping fluids containing solid materials consists of a pump housing (1) and an impeller (2) arranged on a rotationally driven shaft. The pump housing (1) comprises a flow chamber with a suction area (4) and a pressure area (5) surrounding the periphery of the impeller (2), as well as an impeller back chamber (6). According to the invention, the gap (3) to the impeller back chamber (6) is completely sealed off from the flow chamber in relation to the pumped fluid with the solid materials contained therein, but a connection of the impeller back chamber (6) to the pressure area (5) is provided in order to enable air supply to and extraction from said impeller back chamber. Essential elements of an arrangement for sealing the gap (3) include a sliding face (10) formed on the impeller (2), an at least partially flexible sealing element (9) sliding at one end (11) on the slide face (10), and the means (15, 15', 16, 16', 17, 17', 18, 18') for air supply to and extraction from the impeller back chamber (6), wherein the sealing element (9) is fixed to a pressure cover closing off the pump housing (1) on the side facing away from the suction area (4). |
