Abstract: A centrifugal pump includes plural pump stages, each comprising an impeller assembly, a stationary disc assembly and a diffuser assembly, all disposed about an impeller shaft. A floating impeller hub seal is supported by a diffuser assembly to minimize fluid recirculation. A thrust washer is disposed around the impeller shaft and is engageable with an impeller hub and the hub seal. A wear ring is secured to a disc assembly and engageable with a wear surface on the impeller.

Abstract: A progressive die for shaping a consecutive series of discs from a strip of relatively stiff material, comprising a series of adjacent die stations including a slot cutting station, a plurality of intermediate stations, and a cut off station, the slot cutting station including cutting means for forming at least one laterally extending slot between adjacent discs while leaving at least one narrow deformable bridge connecting the adjacent discs, the intermediate stations including cutting means for shaping the discs, and the cut off station including cutting means for severing the bridge. A strip of relatively stiff material includes a series of consecutive discs formed along the length thereof, at least two adjacent discs having at least one laterally extending slot therebetween and at least one narrow deformable bridge connecting the adjacent discs.