1. Working principle and structural characteristics of filter lift pump
The drive of an ordinary centrifugal pump is to connect the impeller shaft of the pump with the electric shaft through a coupling, so that the impeller and the electric motor rotate together and work. The filter lift pump is an unsealed pump, and both the pump and the driving motor are sealed in a pressure vessel filled with the pumped medium. This pressure vessel is only statically sealed, and is provided with a rotating magnetic field by a wire group to drive the rotor. This structure eliminates the rotary shaft sealing device that traditional centrifugal pumps have, so it can achieve no leakage.
The filter lift pump connects the pump and motor together, and the rotor of the motor and the impeller of the pump are fixed on the same shaft. A shielding sleeve is used to separate the rotor and stator of the motor. The rotor operates in the medium being transported, and its power is transmitted to the rotor through the stator magnetic field.
In addition, the manufacturing of the filtration lift pump is not complicated, and its hydraulic end can be designed and manufactured according to the structural type and relevant standards and specifications commonly used in centrifugal pumps.
2. Advantages and disadvantages of filtration lift pumps
2.1 Advantages of Filter Lift Pump
(1) Fully enclosed. There is no dynamic seal in the structure, only a static seal at the pump casing, which can achieve no leakage, especially suitable for transporting flammable, explosive, precious liquids, toxic, corrosive, and radioactive liquids.
(2) High security. The rotor and stator each have a shielding sleeve to prevent the motor rotor and stator from coming into contact with materials. Even if the shielding sleeve ruptures, there is no risk of external leakage.
(3) Compact structure with minimal footprint. The pump and motor are integrated, and disassembly does not require aligning the center. Low requirements for the base and foundation, with minimal daily maintenance workload and low maintenance costs.
(4) Smooth operation, low noise, no need to add lubricating oil. Due to the absence of rolling bearings and motor fans, there is no need to add lubricating oil and the noise is low.
(5) Widely used. It can meet the requirements for various working conditions such as high temperature, high pressure, low temperature, and high melting point.