The invention provides a cryogenic liquid pump system, having a first end with at least an insulating lid and motor; a second end, wherein the second end is a pump, said pump comprising an impeller; and a gas release plate upstream of the impeller; and a shaft disposed between the first end and the second end, wherein the motor imparts mechanical energy to the pump through the shaft. Also provided is a method for preventing cavitation of a cryogenic liquid in a cryogenic pump, the method having the steps of constantly maintaining pressure on the liquid in the pump and evacuating gas bubbles that form within the pump.

A pump for a fluid which can be blood has a stator housing and a rotor hub with leading and trailing portions and an intermediate portion disposed therebetween. At least one impeller blade at the leading portion drives circumferential and axial components of a flow into a pump annulus or intermediate pathway portion. At least one stator blade extends radially inward from the stator housing within the intermediate pathway portion and is configured to reduce a circumferential component of the flow.

A boost pump includes a boost cover and a main pump housing engaged opposite to the boost cover with an impeller rotatably engaged between the boost cover and main pump housing. The impeller includes an inducer section comprising a hub including a plurality of axial blades extended therefrom, each of the plurality of blades including a root, a tip, first and second surfaces, wherein the each of the first and second surfaces is defined in TABLE 1. The impeller includes an impeller section comprising a shroud extending from the hub including a plurality of radial blades extended therefrom. Each of the plurality of blades can include including a root, a tip, and opposed pressure and suction sides extending from the root to the tip, wherein the each of the pressure and suction sides is a surface defined in at least one of TABLES 2-4.

An inducer includes a hub and a blade which radially protrudes from the hub and is helically provided. The inducer has a thick portion in which a first distance and a second distance coincides with each other in a region outside a position at which a height ratio of the blade is 0.5 while the first distance is shorter than the second distance in a region inside the position at which the height ratio of the blade is 0.5, in which the height ratio is a ratio of a distance from a connection portion between the hub and a root portion of the blade with respect to a height of the blade which is a distance from the connection portion between the hub and the root portion of the blade to a tip portion of the blade in the radial direction of the blade.

An impeller includes: main vanes which are provided in a front stage section of a hub so as to connect an outer surface of the front stage section and an inner surface of a shroud, and are arranged at intervals in a circumferential direction of the hub, wherein the main vanes generate an oblique flow of crude oil; and splitter vanes which are provided in a rear stage section of the hub so as to be connected to an outer surface of the rear stage section, and are arranged at intervals in the circumferential direction, wherein the splitter vanes generate an axial flow of the crude oil.

An electrical submersible pump (ESP) assembly. The ESP assembly comprises an electric motor having a first drive shaft; a seal section having a second drive shaft that is coupled to the first drive shaft; a third drive shaft that is coupled to the second drive shaft; and an axial flow centrifugal pump stage, wherein the centrifugal pump stage comprises an impeller coupled to the third drive shaft and a diffuser, wherein the impeller defines a plurality of impeller vanes attached between an impeller hub and an impeller shroud, wherein the impeller shroud is a straight-walled cylindrical shape, wherein the diffuser defines a plurality of diffuser vanes attached between a diffuser hub and a diffuser shroud, and wherein the diffuser shroud is a straight-walled cylindrical shape.