SINGLE-STAGE CENTRIFUGAL PUMPING UNIT

The invention relates to mechanical engineering, namely to pumping installations designed for pumping water, water solutions, as well as oil, oil products and the like through the main, process and auxiliary pipelines, and is directed toward providing a single-stage centrifugal pumping unit which demonstrates peak efficiency in non-nominal modes while having a simplified design and being universal in nature. To this end, a single-stage centrifugal pumping unit comprises a centrifugal single-stage double entry pump, an electric drive motor, a coupling, connecting their shafts, a support frame for mounting the pump housing and the electric motor thereon, a housing, which consists of a base and a cover, inlet and outlet manifolds, a rotor with an impeller mounted thereon, the rotor being installed in support bearings, and a volute configured according to the invention in the form of a separate, independent component, and parts of the outside surface thereof, which are intended to be accommodated in cradles provided for this purpose in the cover and the housing, correspond to the shape of the surfaces of said cradles. The impeller and the volute are replaceable as a pair, the parameters of the impeller and the volute in each pair are calculated to provide maximum efficiency while ensuring the requisite feed and pressure. The replaceable volutes are made as an integrated cast component and comprise a baffle separating the fluid flow during the movement.