An implantable blood pump includes a tube including an inner wall, and wherein during operation of the blood pump, the impeller rotates within the tube and a distance between the inner wall of the tube and the thrust bearing decreases as a speed of the impeller increases.

An implantable blood pump includes a tube including an inner wall, and wherein during operation of the blood pump, the impeller rotates within the tube and a distance between the inner wall of the tube and the thrust bearing decreases as a speed of the impeller increases.

A floating liquid intake for a liquid suction removal system, the liquid intake comprising housing defining an internal cavity. The housing has a hollow and buoyant annular body, an upper cover and a lower cover. The internal cavity is formed between the upper and lower covers. A substantially annular inlet is formed in the annular body for ingress of liquid into the cavity. The annular body has a buoyancy sufficient for the liquid intake to float in a liquid with the annular inlet submerged below the surface of the liquid in which the liquid intake is floating. A pipe extends into the cavity and the pipe includes an inlet that in use is open below the surface of the liquid within the cavity. The pipe extends outside of the cavity for connection to a liquid suction removal system.

A floating liquid intake for a liquid suction removal system, the liquid intake comprising housing defining an internal cavity. The housing has a hollow and buoyant annular body, an upper cover and a lower cover. The internal cavity is formed between the upper and lower covers. A substantially annular inlet is formed in the annular body for ingress of liquid into the cavity. The annular body has a buoyancy sufficient for the liquid intake to float in a liquid with the annular inlet submerged below the surface of the liquid in which the liquid intake is floating. A pipe extends into the cavity and the pipe includes an inlet that in use is open below the surface of the liquid within the cavity. The pipe extends outside of the cavity for connection to a liquid suction removal system.

A vertically-elongated member, which is preferably a support post used in a molten metal pump, includes a ceramic tube and tensioning structures to add a compressive load to the tube along its longitudinal axis. This makes the tube less prone to breakage. Another vertically-elongated member, such as a support post, includes one or more reinforcement members to help alleviate breakage. A device, such as a pump, used in a molten metal bath includes one or more of such vertical members.

A device for pumping molten metal includes a pump configured to pump molten metal, wherein the pump comprises (i) a motor, (ii) a shaft having a first end connected to the motor, and a second end connected to a rotor, wherein the rotor is configured to push molten metal upwards as it rotates. At least part of the shaft and the rotor are positioned in a conduit of a riser. The riser has an outer surface, a front, a bottom, a two-stage conduit, an inlet and an outlet above the inlet and below the motor. The two-stage conduit has a lower stage and a an upper stage, wherein the lower stage is generally cylindrical and the upper stage has a circular cross-sectional portion and one or more lobes extending from and in communication with the circular cross-sectional portion.

A device for pumping molten metal includes a pump configured to pump molten metal, wherein the pump comprises (i) a motor, (ii) a shaft having a first end connected to the motor, and a second end connected to a rotor, wherein the rotor is configured to push molten metal upwards as it rotates. At least part of the shaft and the rotor are positioned in a conduit of a riser. The riser has an outer surface, a front, a bottom, a two-stage conduit, an inlet and an outlet above the inlet and below the motor. The two-stage conduit has a lower stage and a an upper stage, wherein the lower stage is generally cylindrical and the upper stage has a circular cross-sectional portion and one or more lobes extending from and in communication with the circular cross-sectional portion.

A blood flow assist system can include an impeller assembly including an impeller shaft and an impeller on the impeller shaft, a primary flow pathway disposed along an exterior surface of the impeller. The system can include a rotor assembly at a proximal portion of the impeller shaft. A secondary flow pathway can be disposed along a lumen of the impeller shaft. During operation of the blood flow assist system, blood can be pumped proximally along the primary flow pathway and the secondary flow pathway. The system can include a sleeve bearing distal the impeller. The system can include a drive unit having a distal end disposed distal a proximal end of the second impeller. The drive unit comprising a drive magnet and a drive bearing between the drive magnet and the impeller assembly.

A blood flow assist system can include an impeller assembly including an impeller shaft and an impeller on the impeller shaft, a primary flow pathway disposed along an exterior surface of the impeller. The system can include a rotor assembly at a proximal portion of the impeller shaft. A secondary flow pathway can be disposed along a lumen of the impeller shaft. During operation of the blood flow assist system, blood can be pumped proximally along the primary flow pathway and the secondary flow pathway. The system can include a sleeve bearing distal the impeller. The system can include a drive unit having a distal end disposed distal a proximal end of the second impeller. The drive unit comprising a drive magnet and a drive bearing between the drive magnet and the impeller assembly.

A blood flow assist system can include an impeller assembly including an impeller shaft and an impeller on the impeller shaft, a primary flow pathway disposed along an exterior surface of the impeller. The system can include a rotor assembly at a proximal portion of the impeller shaft. A secondary flow pathway can be disposed along a lumen of the impeller shaft. During operation of the blood flow assist system, blood can be pumped proximally along the primary flow pathway and the secondary flow pathway. The system can include a sleeve bearing distal the impeller. The system can include a drive unit having a distal end disposed distal a proximal end of the second impeller. The drive unit comprising a drive magnet and a drive bearing between the drive magnet and the impeller assembly.