Abstract: In accordance with the present invention, an impeller for use in a centrifugal pump has at least one vane the radially outer terminal end of which is configured to produce a flow velocity profile that controls and reduces the wear caused by slurry fluid being expelled from the impeller on the inner surface of the pump casing. The impeller vanes of the present invention are generally configured with a radially outwardly extending portion, as compared with the conventional straight or concave edge of an impeller vane. The outwardly extending portion may vary in shape, but is selected to produce a flow velocity profile that reduces wear in the pump casing.

Abstract: A pump casing for a centrifugal pump of the type that is used to process abrasive slurries is disclosed having at least one side or side liner that has a radially extending portion oriented toward the cutwater of the pump casing to localize the abrasive wear caused by the abrasive slurries to the side of the pump casing. The side liner of the pump is configured with a perimeter edge that is non-circular. The pump casing may preferably be configured with an open cutwater configuration or other suitable configuration for localizing wear to the sides of the casing.

Abstract: Centrifugal pumps suffer from wear of the annular seal (1) between the impeller (2) and the casing or side liner (3), due to the returning flow of the rejoining fluid (9). The present invention ameliorates this problem by having the clearance of the annular seal (10, 11) at least adjacent the inlet (6) of the impeller (2) sloping, in the direction of the main fluid flow (7) into the impeller inlet (6), at an angle of between 0.degree. and 60.degree. to the axis of rotation of the impeller (2).

Abstract: A rotary mechanical seal for a rotating shaft passing into a pressure vessel, the seal having stationary and rotating seal rings (12) with at least one of the rings (12) supported in an axially biased holder (9), characterized by an elastomeric annular seal (11) held in a groove, which groove is so designed as to obviate clogging or crystallizing in the gap between the seal face holder (9) and the housing (10). the groove has a protrusion located on its outer edge which has sloped inner and outer faces to cooperate with the annular elastomeric seal (11) so that the seal protrudes past or is flush with the edge.

Abstract: A centrifical slurry pump impeller comprises auxilliary vanes located on at least one side surface thereof, an annular projection joining the auxilliary vanes at or adjacent the periphery of the impeller, and at least one further projection extending between adjacent auxilliary vanes and spaced substantially from both ends of the adjacent auxilliary vanes to form pockets intermediate the adjacent auxilliary vanes with the annular projection, thereby to limit recirculation of the working fluid of the pump along the face of the impeller containing the auxilliary vanes.