Device for preventing or essentially reducing partial-load cavitation damage in a centrifugal pump unit

摘要

Such a device can be created at minimum expense and avoiding cross-sectional constrictions in the liquid-carrying main line in that the intake line of the single centrifugal pump or the intake line of the fore pump is interrupted at at least one place forming an axial gap in each case, that the peripheral surface in the axial gap on a level with the intake line outside diameter is the annular aperture area of a convergent ring nozzle, the inlet aperture of which opens in a hydraulic water chamber enclosing the intake line, to which chamber pressurised water can be fed in by way of a line connected to the pressure line carrying the so-called minimum quantity, and that the part of the intake line adjoining the axial gap and facing the centrifugal pump has a constant cross-section over its length.