MULTISTAGE CENTRIFUGAL PUMP Russian patent published in 2006 - IPC F04D1/06 F04D29/41 F04D29/06 

FIELD: mechanical engineering; pumps.

SUBSTANCE: proposed pump has housing with guide vane assembly, working impellers fixed on shaft by stop placed before impeller of first stage, and radial supports of shaft. Pump is provided with shaft sealing unit arranged from side of suction channel and hydraulic balancing device in unloading space of housing including unloading disk installed on shaft and support member secured on housing. Space enclosed between unloading disk and support member communicates with pump pressure channel through clearance between impeller of last stage and housing. Shaft sealing unit secured on housing has cylindrical casing with stop bead, jacket hermetically enclosing the shaft, axially movable bushing sealed in casing, spring located between stop bead and axially movable bushing, pair of sealing rings secured respectively, on bushing and jacket and engaging through flat surfaces. Each radial support is provided with pair of holders with antifriction inserts placed one into the other. Through longitudinal channels are made between holders. Inner holder of one of radial supports is clamped between jacket of shaft sealing unit and stop member arranged on shaft. Inner holder of other support is clamped between unloading disk and last stage impeller, end face of shaft is located in unloading space, and hole in casing to which pipeline is connected communicating with unloading space.

EFFECT: simplified design, reduced overall dimensions of pump.

7 cl, 5 dwg