Methods for troubleshooting and repairing stainless steel magnetic pump failures

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Methods for troubleshooting stainless steel magnetic pump failures: 1. Insufficient flow rate in the stainless steel magnetic pump: The main reasons for insufficient flow rate include damaged impellers, insufficient rotational speed, excessive head pressure, and blockages caused by debris inside the pipes. 2. Insufficient head of the stainless steel magnetic pump: The reasons for this fault include air present in the medium being transported, damaged impellers, insufficient rotational speed, too high specific gravity of the liquid being transported, and excessive flow rate. 3. Damage to the bearings of stainless steel magnetic pumps: If the pump runs out of water or if there are impurities inside the pump, this can lead to damage to the bearings. If the coaxiality requirement between the inner and outer magnetic rotors of a cylindrical coupling is not ensured, it will also directly affect the lifespan of the bearings. 4. Pump shaft fracture: The main reason for the pump shaft to break is that the shaft is twisted apart due to the pump running idle, causing the bearings to grind dryly. Upon disassembling the pump for inspection, it can be seen that the bearings are severely worn. The main way to prevent the pump from breaking is to avoid running it without any load. 5. Stainless steel magnetic pump fails to deliver liquid: The inability to pump liquid is one of the most common faults that occur in pumps, and there are various reasons for this. First, check whether there are any air leaks in the pump’s suction line, ensure that any air in the suction line has been removed, verify that the amount of liquid filled in the pump is sufficient, and check for any obstructions in the suction line. It is also necessary to check whether the pump is running in reverse (especially after replacing the motor or after repairing the power supply circuit), as well as to consider whether the pump’s suction height is too high. If the problem remains unresolved 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 fitted to the pump shaft. It is worth noting that the pump has been repaired several times with no problems found; attention should be paid to whether the coupling is working properly. Bearings, inner rotors, and spacers all generate heat during operation, which raises the working temperature. This not only reduces the power transmitted but also causes significant problems for pumps that are used to transport volatile liquids. The power transmitted by the magnet follows a continuously decreasing curve as the temperature rises. Generally, below the operating limit temperature of the magnet, the decline in its transmission capacity is reversible, whereas above this limit temperature it becomes irreversible; that is, once the magnet is cooled, the lost transmission capacity cannot be restored. Under special circumstances, when slippage (loss of synchronization) occurs in the magnetic coupling, the eddy current heat generated within the spacer increases sharply, causing a rapid rise in temperature. If this is not addressed promptly, it can lead to demagnetization of the magnets, resulting in the failure of the magnetic coupling. Therefore, magnetic pump should be equipped with a reliable cooling system. For media that are difficult to vaporize, the cooling circulation system generally draws the fluid flow from the outlet of the impeller or pump, sends it through the bearings and magnetic drive components, and returns it to the inlet. 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. For high-temperature media, cooling measures must be taken to ensure that the magnetic coupling does not exceed its operating temperature limit.