Torque transfer system for centrifugal pumps

A centrifugal pump comprising:

• a module, comprising:
• a rotatable shaft;
• a series of impellers stacked on the rotatable shaft, each impeller comprising a hub secured to the rotatable shaft by a key, the series of impellers comprising an uppermost impeller and a lowermost impeller;
• a flange sleeve keyed to the rotatable shaft above the uppermost impeller;
• a standoff sleeve keyed to the rotatable shaft below the lowermost impeller;
• and
• each impeller of the series of impellers comprising a stepped edge on a top end of the hub and a stepped edge on a bottom end of the hub, wherein ends of opposing hubs are inversely stepped so as to interlock with a first clearance between longitudinal portions of the opposing stepped edges;
• the top end of the hub of the uppermost impeller interlocked with a stepped bottom edge of the flange sleeve with a second clearance between longitudinal portions of the opposing stepped edges;
• and
• the bottom end of the hub of the lowermost impeller interlocked with a stepped upper edge of the standoff sleeve with a third clearance between longitudinal portions of the opposing stepped edges.

A torque transfer system for a centrifugal pump comprising:

• a rotatable shaft extending longitudinally through a hub of an impeller;
• the hub coupled to the rotatable shaft by a key;
• a sleeve secured to the rotatable shaft by the key, the sleeve above the impeller and comprising:
• a bearing surface extending circumferentially around the rotatable shaft;
• a driving surface, the driving surface between the bearing surface and a top portion of the hub;
• and
• the driving surface extending partially around the rotatable shaft to form a stepped bottom edge of the sleeve;
• the top portion of the hub stepped inversely to the bottom edge of the sleeve with a clearance between longitudinally extending portions of the top portion of the hub and the bottom edge of the sleeve;
• wherein upon reduction of torque transference between the key and the sleeve, the clearance closes such that contact between the longitudinally extending portions maintains rotation of the sleeve with the rotatable shaft.

A centrifugal pump comprising:

• a rotatable shaft;
• a sleeve extending axially below a radially extending flange, the sleeve keyed to the rotatable shaft and comprising:
• a bearing surface extending circumferentially around the rotatable shaft a first axial length below the flange,
• a driving surface extending from and below the bearing surface partially around the rotatable shaft a second axial length below the bearing surface, the second axial length defined by a pair of longitudinally extending edges, and
• wherein a bottom edge of the bearing surface, a bottom edge of the driving surface and the pair of longitudinally extending edges together form a stepped sleeve edge;
• an impeller around the rotatable shaft below the sleeve, the impeller comprising a hub;
• a top end of the hub comprising a hub edge stepped inversely to the sleeve edge;
• and
• the hub edge and the stepped sleeve edge interlocked.