A canned motor pump is a combination of a centrifugal pump and a squirrel cage induction motor built together into a single hermetically sealed unit. The pump impeller is normally of the closed type and is mounted on one end of the rotor shaft that extends from the motor section into the pump casing. The rotor is submerged in the fluid being pumped and is therefore "canned" to isolate the motor parts from contact with the fluid. The stator(C) is also "canned" to isolate it from the fluid being pumped. Bearings(D) are submerged in system fluid and are, therefore, continually lubricated.
The canned motor pump has only one moving part, a combined rotor-impeller assembly that is driven by the magnetic field of an induction motor. A portion of the pumped fluid is allowed to recirculate through the rotor cavity to cool the motor and lubricate the bearings. The stator windings and rotor armature are protected from contact with the recirculating fluid by a corrosion resistant, non-magnetic, alloy liner that completely seals or "cans" the stator winding.
Modifications to the recirculation flow system are available to allow canned motor pumps to be used in any application including fluids up to 842°F (450°C), volatile liquids, and liquids with solids.
For more information on canned motor pumps, please download materials of canned motor pumps in Customer Manu.