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Common faults and troubleshooting methods of magnetic drive pumps: Common faults that occur during the use of magnetic drive pumps include damaged bearings, broken shafts, insufficient flow rate, inadequate head pressure, and the pump’s inability to deliver liquid. I. Damage to the bearings of magnetic drive pumps: The bearings in magnetic drive pumps are made of high-density carbon; damage to these bearings can occur if the pump runs out of water or if there are impurities inside the pump. If the coaxiality between the inner and outer magnetic rotors of a cylindrical coupling is not ensured, it will also directly affect the lifespan of the bearings. II. Breakage of the shaft in magnetically driven pumps: The shafts of magnetically driven pumps are made of 99% alumina ceramic, and the main reason for their breakage is twisting of the shaft due to the pump running without liquid, which causes dry friction between the bearings. Upon disassembling the pump for inspection, it was found that the bearings were severely worn. The main method to prevent pump breakage is to avoid running the pump without load. III. Lack of flow: The main reasons for a lack of flow include damaged impellers, insufficient rotational speed, excessive head, and blockages caused by debris inside the pipes. IV. Lack of head. The reasons for a lack of head include: air in the fluid being pumped, damaged impellers, insufficient rotational speed, too high specific gravity of the liquid being pumped, and excessive flow rate. V. The magnetic drive pump fails to deliver liquid. This is the most common problem with magnetic drive pumps, and there are various reasons for it. First, check whether there are any air leaks in the pump’s suction line, verify that the air in the suction line can be expelled, ensure that the amount of liquid filled in the magnetically driven pump is sufficient, and check for any obstructions in the suction line. It is also necessary to verify whether the pump is running in reverse (especially after replacing the motor or after repairing the power supply circuit), as well as to ensure that the pump’s suction height is not too high. If the problem cannot be resolved after the above checks, the pump can be disassembled to check whether the pump shaft is broken; it is also necessary to verify that the rotating and stationary rings of the pump are in good condition, as well as whether the entire rotor can move slightly axially. If axial movement is difficult, check whether the carbon bearing is too tightly attached to the pump shaft. If the magnetically driven pump has been repaired several times with no problems found, attention should be paid to whether the magnetic coupling is working properly. Bearings, internal magnetic rotors, and spacers all generate heat during operation, which raises the working temperature. This not only reduces the power transmitted but also poses significant challenges for magnetic pumps used to transport liquids that are prone to vaporization. The power transmitted by the magnetoid follows a continuously decreasing curve as the temperature rises. Generally, below the operating limit temperature of the magnetoid, this decrease in transmission capacity is reversible; however, above that limit temperature it becomes irreversible – that is, once the magnetoid cools down, the lost transmission capacity cannot be restored. Under special conditions, when slippage (loss of synchronization) occurs in the magnetic coupling, the eddy current heat generated within the spacer increases sharply, leading to a rapid rise in temperature. If this is not addressed promptly, it can cause the magnets to lose their magnetism, resulting in the failure of the magnetic coupling. Therefore, magnetic drive pumps should be equipped with a reliable cooling system. For media that are difficult to vaporize, the cooling circulation system typically draws the fluid flow from the outlet of the impeller or pump, and it returns to the inlet through the bearings and magnetic drive. For media that are easy to vaporize, heat exchangers should be added or the fluid flow should be directed to a storage tank outside the pump, in order to prevent heat from returning to the inlet. For media containing solid impurities or ferromagnetic contaminants, filtration should be considered. In the case of high-temperature media, cooling measures should be taken to ensure that the magnetic coupling does not exceed its operating temperature limits. When considering whether the speed is sufficient, it is first necessary to check whether the motor’s own speed is normal; this can be done using a tachometer. Once the motor’s speed is normal, it is possible to check whether there is any slippage in the magnetic coupling.