Scope of application of canned motor pumps

Based on the temperature, pressure, viscosity, and presence or absence of particles of the liquid being transported, shielded pumps can be classified into the following types.

The basic type of conveying medium has a temperature not exceeding 120°C and a head not exceeding 150m. Other various types of canned pumps can be obtained by modifying and improving the basic type. In the reverse circulation type of canned pump, the flow direction of the liquid for bearing lubrication, cooling, and motor cooling is exactly opposite to that of the basic type. Its main characteristic is that it is less prone to cavitation, making it particularly suitable for conveying liquids that are prone to vaporization, such as liquefied petroleum gas and methyl chloride. The high-temperature type generally conveys media with a maximum temperature of 350°C, a maximum flow rate of 300m3/h, and a maximum head of 115m, suitable for high-temperature liquids such as thermal medium oil and hot water. The high-melting-point type pump and motor are jacketed, which greatly improves the heat resistance of the motor. It is suitable for high-melting-point liquids with a maximum temperature of 250°C. Steam or liquid at a certain temperature can be passed through the jacket to prevent crystallization of high-melting-point liquids. The high-pressure type canned pump has a high-pressure vessel as its shell, enabling the multistage pipeline pump to withstand high system pressure. To support the shielding sleeve under internal high pressure, the stator coil can be used to bear the pressure. The self-priming type pumps discharge liquid through automatic air extraction when the suction pipe is not fully filled with liquid, making it suitable for extracting liquid from underground containers. The multistage type is equipped with multiple impellers, suitable for high-head fluid conveyance, with a maximum head of up to 400m. The slurry type is suitable for conveying liquids mixed with a large amount of slurry.