A casing liner used for a sewage pump includes a surface to face an edge of a blade of an impeller when the casing liner is assembled with the impeller into the sewage pump. At least one groove with given width is formed in at least a part of the surface. The groove includes a first section with given depth, which is located on the side close to a rotational center of the impeller, a second section smaller in depth than the first section, which is located on the side far from the rotational center of the impeller, and a third section that is an inclined face connecting the first and second sections, the first to third sections being arranged in a width direction of the groove.

An electric centrifugal pump having a motor housing, a pump head, a containment shell, and a rotor assembly consisting of a pump impeller and a permanent magnet rotor, wherein the pump head with the containment shell defines a wet chamber, in which the rotor assembly is arranged rotationally around a longitudinal motor axis, the containment shell with the motor housing defines a dry chamber, in which a wound stator is arranged, and the permanent magnet rotor is arranged within the stator and a hollow-cylindrical region of the containment shell. Particle accumulations in the region between the containment shell and the permanent magnet rotor cannot occur or can only occur to a very minor extent and that the consequences of impurities in the wet chamber are reduced in order to prevent premature wear or a blockage of the centrifugal pump.

A housing element for a pump or of a pump has a housing inner wall defining a flow channel for a fluid medium extending along a central axis. The cross section of the flow channel is greater in a main flow direction and the housing inner wall has a surface structure configured such that it counteracts a return flow counter to the main flow direction along the housing inner wall of the fluid medium. The housing element can act as a pump housing and be combined with a pump.

A centrifugal pump (1) including: a pump housing (3) enclosing a pump chamber (13), the pump chamber (13) including a suction inlet (15) and a pressure outlet (17); an impeller (19) rotatably arranged within the pump chamber (13) for being driven to rotate about a rotor axis (R), the suction inlet (15) being located coaxial with the rotor axis (R); and at least one stationary scraper (39). The impeller (19) includes an impeller base (31) and at least one or more impeller vanes (33) extending from the impeller base (31) towards the suction inlet (15). Each of the impeller vanes (33) includes a radially innermost vane path (45) describing during impeller rotation a central volume (41) that is wider towards the suction inlet (15) than towards the impeller base (31) and configured to receive the at least one scraper (39) projecting from the suction inlet (15) into the central volume (41).

A pump comprising an impeller having a hub base and an impeller body. The impeller body comprises a base which is concentric relative to a rotational axis of the impeller, and at least one eccentric apex.

Embodiments of the invention provide a cutting assembly for a chopper pump. The cutting assembly includes a cutting insert having a cutting blade extending radially therefrom, and an impeller having a central hub, a plurality of vanes, and an insert surface. The insert surface defines an axial recess that is dimensioned to receive the cutting insert therein. The cutting assembly further includes a cutting plate having a plate hub with a cutting extension protruding radially inward therefrom. Rotation of the impeller rotates the cutting blade past the cutting extension.

A cutter assembly configured for a grinder pump and including a cutter wheel and a cutter disc that interact with each other. The cutter wheel includes a shaft portion that is configured to interact with a central hole of the cutter disc, a hub portion that is connected to the shaft portion and at least two main cutting edges that in the radial direction extend outwards from the hub portion and that are configured to interact with a set of cutting holes of the cutter disc. The shaft portion includes an axially extending cutting recess. The hub portion includes only one radially extending cutting recess. The cutter disc includes a suction side, a central hole that is configured to interact with the shaft portion of the cutter wheel and a set of cutting holes that open in the suction side radially outside the central hole.

A well fluid centrifugal pump has a number of stages, each of the stages having an impeller and a diffuser. The impeller has vanes curving outward from a central intake area to a periphery of the impeller. Each of the vanes has a convex side and a concave side. An upstream slot and a downstream slot extend through the vane from the convex side to the concave side. Each of the slots has an entrance on the convex side and an exit on the concave side, with the entrance being located upstream from the exit. The entrance has a greater cross-sectional area than the exit to divert well fluid flowing along the convex side to the concave side to remove accumulated gas.

An impeller for a centrifugal pump for pumping fluid containing solid particles includes: a rear side wall; a front side wall; a plurality of vanes located between the rear side wall and the front side wall, each vane having an outer edge and a vane width in an axial direction of the impeller. At least one of a periphery of the rear side wall or a periphery of the front side wall projects by a radial distance beyond the outer edges of the vanes, the radial distance being at least 0.5 times the vane width.

A centrifugal pump for pumping fluid includes a volute having an upstream inlet that receives the fluid and a downstream outlet that discharges the fluid. An impeller is disposed in the volute and comprises a plurality of impeller vanes. The impeller is configured to rotate about an axis of rotation so that the plurality of impeller vanes accelerates the fluid radially outwardly from the upstream inlet to the downstream outlet. The impeller is further configured to discourage air-lock of the centrifugal pump by expelling air away from the upstream inlet as the impeller rotates about the axis of rotation.