Centrifugal pump

Abstract

A centrifugal pump which is used to convey a liquefied gaseous fluid has a housing with an inlet which extends axially and an outlet which extends radially of the pump shaft. The shaft drives the impellers of several coaxial stages including a first stage which is a full-admission standard-impeller-type stage, a last stage which is a partial-admission self-priming regenerative stage, and a compressor stage upstream of the first stage. The pump can convey liquefied gases from a vessel which is located at a level well below the housing. If the liquefied fluid is converted back into a gaseous fluid as a result of prolonged idleness of the pump, the compressor stage reconverts the gas into a liquid and such liquid is then conveyed to the regenerative stage by the first stage so that the regenerative stage is ready to immediately proceed with the self-priming operation.

Dependencies are inferred from the claim text.