GB1132751A - Rotary pump - Google Patents

Abstract

1,132,751. Centrifugal pumps; turbines. WORTHINGTON CORP. Oct. 26, 1965 [Feb. 24, 1965], No.45226/65. Headings F1C and F1T. A submersible centrifugal pump for pumping ballast water from a compartment of a ship comprises an impeller 28 which draws the water through an inlet passage 12 and delivers it via a diffuser passage 50 to an outlet 55 connected to a rising main. The pump is driven by a turbine comprising rotor blading 30 formed on the impeller 28 or otherwise connected to it. An auxilary pump located above the compartment delivers water via a downpipe and an inlet passage 16 to nozzle vanes 33 and thence through the turbine rotor blading 30 to drive the turbine. On leaving the blading 30, the water enters the diffuser passage 50 to join the water discharged by the impeller 28 and to exert an ejector effect which assists the pumping action. The diffuser vanes 54 have projections adjacent the rotor blading 30 to form ejector vanes. Alternatively, separate ejector vanes may be used. The diffuser passage 50 reduces the fluid velocity to minimize the losses incurred in passing around the obstacles 16, 24. Thereafter, the velocity is increased towards the outlet 55. The turbine may be driven by a liquid different from that being pumped. The two liquids thereby mixed together may subsequently be separated in a settling tank or a centrifuge. Alternatively, the turbine may be driven by steam which condenses and mixes with the pumped water. The turbine nozzle may be of partial admission type. The impeller 28 may be carried by a shaft journalled in a bearing. Alternatively, it is carried by a bush 66 which is journalled on a stationary shaft 27, either directly as shown or through the intermediary of ball bearings. Lubricant, which may be the fluid being pumped and may be cleaned by passing it through a cyclone separator, is supplied through passages 81, 82, 83, 84 into chambers 85, 85' formed by flats 61, 62 on the shaft 27, and returns to the pump inlet via the clearance between the bush 66 and a thrust collar 69 and also via passages 90. In an alternative arrangement, Figs. 18-20 (not shown), the pump discharges through a volute (201), while the turbine driving fluid is admitted through a centrally disposed inlet (200) at the top of the casing.