MODULAR, MULTI-STAGE, INTEGRAL SEALED MOTOR PUMP WITH INTEGRALLY-COOLED MOTORS AND INDEPENDENTLY CONTROLLED ROTOR SPEEDS

摘要

An integral motor pump module directs at least 90% of its rotor discharge over at least 50% of its motor housing surface, thereby cooling the motor with little or no need for a separate flow path. The discharge can flow through an annulus formed between the motor and pump housings, and can extend over substantially all of the sides and rear of the motor housing. The rotor can be fixed to a rotating shaft, or rotate about a fixed shaft, which can be threaded into the motor and/or module housing. A plurality of the modules can be combined into a multi-stage pump, with rotor speeds independently controlled by corresponding variable frequency drives. The motor can be a radial or axial permanent magnet or induction motor. A separate cooling flow can provide additional cooling e.g. when pumping heated process fluids. Embodiments include guide vanes and/or diffusers.