(1) magnetic pump shaft breakage. CQB-type magnetic pump shaft material used is 99% of alumina ceramic, the main reason for the shaft is broken, because the pump runs dry, the shaft bearing dry wear and tear. Open the pump inspection can be seen when the bearing has been seriously damaged to prevent the pump broken off the main method is to avoid the air pump running. (2) magnetic pump bearing damage. CQB magnetic pump bearings are made of high-density carbon material, in case of pump water or pump impurities, it will cause the bearing damage. Cylindrical shaft coupling inside and outside the rotor between the coaxial requirements if not guaranteed, will also directly affect the bearing life. (3) magnetic pump can not play the liquid. Magnetic pump can not play the liquid pump is the most prone to failure , its reasons are more. First of all, check whether the pump suction pipe leaks, check the suction pipe air is exhausted, the amount of liquid filled in the magnetic pump is sufficient, inhalation tube whether there is debris clogging, check whether the pump is reversed (Especially after changing the motor or overhauling the power supply line), you should also pay attention to whether the suction height of the pump is too high. If the above inspection still can not be solved, the pump can be disassembled to check whether the pump shaft is broken or not. Check whether the moving ring and the static ring of the pump are intact, and whether the entire rotor can move in a small amount of axial direction. If the axial movement difficulties, can check whether the carbon bearing with the pump shaft is too close. It is noteworthy that the magnetic pump repair several times to check the problem, should pay attention to the work of the magnetic coupling is normal. Bearings, inner magnetic rotors and spacers generate heat during operation, which increases the operating temperature and on the one hand reduces the power delivered and on the other hand gives rise to a great deal of hassle for the magnetic pumps that convey easily vaporized liquids. Magnetically transmitted power with temperature increases is a continuous decline in the curve, usually below the working temperature limit of the magnet, the decline of its transmission capacity is reversible, but above the limit temperature is irreversible, that is, the magnet cooling After losing the ability to pass the transfer can no longer be restored. Under special circumstances, when the magnetic coupling slips (out of step), the eddy current heat in the spacer increases rapidly and the temperature rises sharply. If it is not processed in time, the magnet will demagnetize and make the magnetic coupling fail. Therefore, the magnetic pump should design a reliable cooling system. The medium is not easy to vaporize, the cooling system is generally circulated by the impeller outlet or pump outlet leads to the liquid flow through the bearing and magnetic drive back to the suction port, the vaporization of the medium, the heat exchanger should be added or the liquid flow to the pump Of the tank, to avoid heat back to the suction port, for solid impurities or ferromagnetic impurities in the media, should consider filtering, high temperature medium, you should consider cooling to ensure that the magnetic coupling does not exceed the working temperature limit. In considering whether the speed is enough, we must first check the motor speed is normal, tachometer available for measurement, the motor speed is normal, you can consider whether there will be magnetic coupling slippage. (4) lack of lift. The reasons for this failure are: transmission medium air, impeller damage, speed is not enough, the proportion of liquid transport is too large, the flow is too large. (5) lack of traffic. The main reasons for the lack of flow are: impeller damage, speed is not enough, the lift is too high, the tube is clogged with debris and so on.