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The use of high-temperature magnetic pumps in the market is no longer a new topic; recently, there has been intense discussion regarding whether such pumps can retain their magnetic properties even at extreme high temperatures. High-temperature magnetic pumps are widely used in petroleum refining, the petrochemical and chemical industries, as well as in other fields, for transporting special petroleum products, dyeing and printing raw materials, and other high-temperature media. The temperature of such media should not exceed 350 degrees Celsius, as exceeding this limit will affect the pump’s operating efficiency. Experts point out that at extreme high temperatures, the magnetism of magnetic pumps disappears; therefore, companies are advised to pay attention to the operating conditions of the medium when using high-temperature magnetic pumps. High-temperature magnetic pumps should operate under specified temperature conditions; it is strictly prohibited for the temperature of the medium to exceed the limits. A platinum resistance temperature sensor can be installed on the outer surface of the magnetic pump’s isolation sleeve to monitor the temperature rise in the gap area, so as to trigger an alarm or shut down the pump when the temperature exceeds a set limit. When in use, the ambient temperature for high-temperature magnetic pumps should be below 40°C, and the motor temperature rise must not exceed 75°C. When a high-temperature magnetic pump is in operation, a small amount of liquid must be used to flush and cool the annular gap between the internal magnetic rotor and the isolation sleeve, as well as the friction pairs of the sliding bearings. The flow rate of the coolant is usually 2%-3% of the pump’s designed flow rate, and the annular gap between the internal magnetic rotor and the isolation sleeve generates high heat due to eddy currents. When there is insufficient cooling lubricant or when the flushing holes are clogged, it will cause the temperature of the medium to rise above the operating temperature of the permanent magnets. This, in turn, leads to the gradual loss of magnetism in the internal magnetic rotor. Constant-pressure water supply and boiler softening systems can also result in the failure of the magnetic drive. When the medium is water or a water-based fluid, the temperature rise in the annular gap area can be maintained at 3–5°C; when the medium is hydrocarbons or oil, it can be maintained at 5–8°C.