Improvements to pumps and components therefor

摘要

A pump side part for use with a shrouded pump impeller, comprising a side wall section rear face including an outer region with an outer edge in a plane which is substantially at right angles to the rotation axis, an inner region with an inner edge and an intermediate region between the outer and inner regions which is inclined inwardly from the said plane in a direction towards the inlet section, the inner region extending from the intermediate region in a direction away from the front face of the side wall section, wherein the outer face of the impeller front shroud and the side part rear face are arranged to be facing one another with a gap therebetween, the rear face being configured so that the cross-sectional dimension of the gap increases in a direction toward the impeller rotation axis in the intermediate region.