The high-temperature magnetic pump is a kind of non-contact torque transmission through a magnetic drive (magnetic coupling) to replace the dynamic seal with a static seal, so that the pump can be completely leak-free. The permanent magnets made of materials have a wide operating temperature range (-45-400 °C), high coercivity, good anisotropy in the direction of the magnetic field, and no demagnetization when the same poles are close to each other. A good source of magnetic fields.
When the high temperature magnetic pump is working, a small amount of liquid must be used to flush and cool the annular gap area between the inner magnetic rotor and the insulating sleeve and the friction pair of the sliding bearing. The flow rate of the coolant is generally 2%-3% of the planned flow rate of the pump, and the annular gap area between the inner magnetic rotor and the insulating sleeve generates high heat due to eddy currents. When the cooling lubricating fluid is not available or the flushing hole is not smooth or blocked, the temperature of the medium will be higher than the working temperature of the permanent magnet, the inner magnetic rotor will gradually lose its magnetism, and the magnetic drive will fail. When the medium is water or water-based liquid, the temperature rise in the annulus region can be maintained at 3-5°C; when the medium is hydrocarbon or oil, the temperature rise in the annulus region can be maintained at 5-8°C.
According to the use of the application, the high-temperature magnetic pump is selected for hot water, and the suction pump is selected for low-level water absorption. In addition, the flow rate and head of the pump should also meet the application requirements. Common disadvantages of high temperature magnetic pumps are:
1. The lift is missing. The reasons for this shortcoming are: there is air in the transport medium, the impeller is damaged, the rotation speed is not allowed, the specific gravity of the transported liquid is too large, and the flow rate is too large.
2. The shaft of the high temperature magnetic pump is broken. The material selected for the pump shaft of the CQB type high temperature magnetic pump is 99% alumina porcelain. The primary reason for the breakage of the pump shaft is that the shaft is twisted and broken due to the dry grinding of the bearing due to the empty operation of the pump. When the pump is disassembled for inspection, it can be seen that the bearing has been seriously worn and the first way to prevent the pump from breaking is to avoid the empty work of the pump.
3. Lack of traffic. The main reasons for the lack of flow are: the impeller is damaged, the rotation speed is not enough, the head is too high, and there is debris in the pipe blocked.
4. The high temperature magnetic pump cannot pump liquid. The fact that the high temperature magnetic pump cannot pump liquid is a disadvantage of the pump, and there are many reasons for it. First of all, check whether there is air leakage in the suction pipe of the pump, check whether the air in the suction pipe is discharged, whether the amount of liquid perfused in the high-temperature magnetic pump is sufficient, whether there is debris in the suction pipe, and also check whether the pump rotates (Especially after replacing the motor or after the power supply line is overhauled), you should also pay attention to whether the suction height of the pump is too high. If the above inspection still cannot be solved, the pump can be disassembled and checked to see if the pump shaft is broken. It should also be checked whether the dynamic and static rings of the pump are intact, and whether the entire rotor can move axially. If the axial movement is difficult, check whether the carbon bearing is too tightly combined with the pump shaft