US Patent 11326607 Balancing axial thrust in submersible well pumps

A first fluid rotor that has a first fluid intake end and a first fluid discharge end. The first fluid rotor includes a shaft and an impeller. A second fluid rotor that has a second fluid intake end and a second fluid discharge end. The second fluid rotor is rotatably coupled to the first fluid rotor to rotate in unison with the first fluid rotor along a shared rotational axis. The first fluid intake end and the second fluid intake end are facing opposite directions. The second fluid rotor includes a second shaft and a second impeller. A first fluid stator surrounds the first fluid rotor. The first fluid stator is aligned along the rotational axis. The first fluid rotor and the first fluid stator form a first fluid stage. A second fluid stator surrounds the second fluid rotor. The second fluid stator is aligned along the rotational axis. The second fluid stator and the second fluid rotor form a second fluid stage. A flow crossover sub is positioned between the first fluid stage and the second fluid stage. The flow crossover sub defines flow passages that fluidically connect the first fluid stage and the second fluid stage. An outer housing surrounds the first fluid stator, the second fluid stator, and the flow crossover sub.