Fault analysis and solutions for acid-alkali resistant magnetic circulation pumps! ~

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The acid and alkali resistant magnetic circulation pump, also known as a magnetically driven pump, is often used for transporting acidic and alkaline chemical substances due to its ability to convey chemical liquids without leakage; hence it is also referred to as an acid-resistant magnetic pump. It has excellent corrosion resistance and can be used to transport various acidic and alkaline liquids such as sulfuric acid, hydrochloric acid, nitric acid, chromic acid, hydrofluoric acid, phosphoric acid, and sodium hypochlorite. (1) Damage to the bearings of the acid- and alkali-resistant magnetic circulation pump. The bearings in such pumps are made of high-density carbon; damage to these bearings can occur if the pump runs out of fluid or if there are impurities inside the pump. If the coaxiality between the inner and outer magnetic rotors of the cylindrical coupling is not maintained, it will also have a negative impact on the lifespan of the bearings.
(2) Insufficient head output of the acid- and alkali-resistant magnetic circulation pump. The reasons for this issue include air present in the fluid being pumped, damaged impellers, insufficient rotation speed, too high specific gravity of the liquid being pumped, or excessive flow rate.
(3) Insufficient flow rate of the acid- and alkali-resistant magnetic circulation pump. The main causes of low flow rate include damaged impellers, insufficient rotation speed, excessively high head pressure, and blockages in the pipes.
(4) The pump fails to discharge liquid. This is a common problem with magnetic pumps, and there are several possible reasons for it. First, check whether there are any leaks in the suction pipeline, ensure that any air in the suction line is removed, verify that enough liquid is present in the pump, and check for any blockages in the suction line. It’s also important to check whether the pump is running in reverse (especially after replacing the motor or repairing the power supply circuit). Additionally, consider whether the suction height of the pump is too high.
(5) Breakage of the pump shaft. The pump shafts in acid- and alkali-resistant magnetic circulation pumps are made of 99% alumina ceramic. The main reason for shaft breakage is dry friction caused by the pump running without fluid, which leads to the shaft breaking. Upon disassembling the pump, it can be seen that the bearings are severely worn. The best way to prevent shaft breakage is to avoid running the pump without fluid.
If these checks do not resolve the problem, the magnetic pump should be disassembled to check whether the shaft is broken. It’s also necessary to check whether the rotating and stationary rings are intact, as well as whether the entire rotor can move slightly axially. If axial movement is difficult, check whether the carbon bearings are too tightly attached to the pump shaft.