Vertical rotatable centrifugal pump

Claim 2

A vertical rotatable centrifugal pump for pumping fluid metals, more particularly sodium, comprising a rotor journalled in a hydrostatic bearing in which the pumped fluid is utilized as a bearing fluid characterized in that the rotor is provided with an auxiliary impeller whose suction side communicates directly with the pressure space of the pump and whose pressure side communicates with the hydrostatic bearing feed and in that the delivery side of the bearing communicates with a low pressure space which communicates through aperatures in the blades of the diffuser with the suction space of the pump.

Claim 3

A pump as claimed in claim 1, characterized in that the outer sleeve of the hydrostatic bearing is fastened to the rotor and the inner sleeve of said bearing is secured in the housing of the pump.

Claim 4

A pump as claimed in claim 1 characterized in that the inner sleeve of the hydrostatic bearing is secured to the rotor and the outer sleeve is fastened in the housing of the pump.

Claim 5

A vertical rotatable centrigufal pump for pumping fluid metals such as sodium, comprising in combination: a vertical drive shaft having a centrifugal impeller fixed to the lower end of said shaft; a housing surrounding said impeller and presenting an inlet opening around said shaft; a diffusor assembly cooperating with said housing to enclose said impeller, said diffusor assembly including a hollow discharge stub disposed centrally below said impeller and a diffusor section leading from the periphery of said impeller to said discharge stub, said diffusor section having spaced inner and outer walls defining a diffusor channel therebetween and said inner wall dEfining an enclosed space with the underside of said impeller, said inner wall having an opening aligned and communicating with said discharge stub so as to provide a source of fluid metal whose pressure is that present in said discharge stub; a hydrostatic bearing supporting the lower end of said shaft, said bearing comprising an inner sleeve and an outer sleeve coaxial with said shaft and defining a gap therebetween, one of said sleeves being connected with said shaft and impeller for rotation therewith and the other of said sleeves being fixed to the inner wall of said diffusor assembly; and an auxiliary pump for inducting fluid metal from said source thereof and discharging it into said gap to flow into said enclosed space, said enclosed space communicating with the inlet side of the first mentioned impeller through passage means extending through said inner and outer walls of the diffusor section, said auxiliary pump comprising an auxiliary impeller having an inlet eye communicating directly with said opening and a periphery communicating directly with said gap at one end of the sleeves, the opposite end of the sleeves discharging directly into said enclosed space.

Claim 6

A vertical rotatable centrigufal pump for pumping fluid metals such as sodium, comprising in combination: a vertical drive shaft having a centrifugal impeller fixed to the lower end of said shaft; a housing surrounding said impeller and presenting an inlet opening around said shaft; a diffusor assembly cooperating with said housing to enclose said impeller, said diffusor assembly including a hollow discharge stub disposed centrally below said impeller and a diffusor section leading from the periphery of said impeller to said discharge stub, said diffusor section having spaced inner and outer walls defining a diffusor channel therebetween and said inner wall dEfining an enclosed space with the underside of said impeller, said inner wall having an opening aligned and communicating with said discharge stub so as to provide a source of fluid metal whose pressure is that present in said discharge stub; a hydrostatic bearing supporting the lower end of said shaft, said bearing comprising an inner sleeve and an outer sleeve coaxial with said shaft and defining a gap therebetween, one of said sleeves being connected with said shaft and impeller for rotation therewith and the other of said sleeves being fixed to the inner wall of said diffusor assembly; and an auxiliary pump for inducting fluid metal from said source thereof and discharging it into said gap to flow into said enclosed space, said enclosed space communicating with the inlet side of the first mentioned impeller through passage means extending through said inner and outer walls of the diffusor section, said auxiliary pump comprising an auxiliary impeller having an inlet eye communicating directly with said opening and a periphery communicating directly with said gap at one end of the sleeves, the opposite end of the sleeves discharging directly into said enclosed space.

Claim 7

A pump as defined in claim 4 wherein said inner wall of the diffusor section is provided with an upstanding stub extending upwardly to a point closely adjacent the underside of the first mentioned impeller and defining said opening, said auxiliary impeller being formed on said underside of the first mentioned impeller and said inner sleeve being on said upstanding stub.

Claim 8

A pump as defined in claim 4 wherein said inner sleeve is secured to said shaft and extends downwardly to a point closely adjacent said opening, and said auxiliary impeller being formed at the lower end of said inner sleeve.