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A chemical shielded pump is a leak-free pump consisting of a shielded motor and a pump. It is mainly composed of a pump body, impeller, stator, rotor, front and rear bearings, and thrust plates. The stator and rotor are separated by a non-magnetic, corrosion-resistant thin-walled sleeve; the rotor is supported by front and rear bearings and is immersed in the conveying medium, hence no type of dynamic seal is required to prevent the leaking of the conveying medium. Generally, chemical shielded pumps are sealless centrifugal pumps. Chemical shielded motor pumps are leak-free; under negative pressure in the pump, external gases cannot be drawn in, making them particularly suitable for operation in vacuum systems. It is also suitable for high-pressure, high-melting-point, and high/low-temperature media. Shielded pumps are compact in structure, small in size, and light in weight. No cooling fan, low noise, wide range of applications, reliable operation, and provides a good working environment. After chemical process shield pumps have been in use for a long time, the temperature of key components such as the bearings rises, which prevents the pump from functioning properly. In such cases, it is necessary to employ certain cooling methods to reduce the pump’s temperature. There are two cooling methods for chemical process shielded pumps: one involves using the circulation of the working medium itself to absorb the heat generated during operation. In other words, the liquid to be filtered is guided from the pump outlet, enters the rear bearing through the motor shaft, and then is sent back to the impeller via the gaps between the rotor and stator as well as channels such as the front bearing, thus forming a circulating cooling system to achieve cooling purposes. Shielded pumps used for transporting ordinary liquids typically employ this method for cooling. Another method is internal cooling of the rotor, that is, using circulating oil to cool the rotor. In the oil holes at both ends of the pump shaft, the oil passes through the shaft ends and into the rotor wall before exiting from the other end; this cooling method can be employed when the pump operates under high pressure differences. The two main cooling methods used for chemical process shielded pumps are the ones mentioned above. In practice, we can choose which cooling method to use based on the temperature and boiling point of the materials involved; however, the former is usually given priority in design.