The magnetic pump manufacturer tells you the use, selection and maintenance points of the magnetic pump
First, the matters needing attention when using the magnetic pump:
(1) After installation, turn the coupling by hand to check the friction.
(2) In order to prevent debris from entering the pump, a filter should be installed at the pump inlet, and the filtration area is 3 to 4 times the cross-sectional area of the pipe.
(3) It is strictly forbidden to be lazy.
(4) The high lift magnetic pump should be equipped with a check valve on the outlet line to prevent the water hammer from suddenly closing.
(5) Opening procedure of the pump: open the inlet valve before starting, fill the pump with the liquid to be delivered, close the outlet valve, point to the motor, check whether the steering of the pump is correct, after the pump starts, after the pump reaches normal operation state, Adjust the outlet valve to the desired opening. Test run for 5 to 10 seconds, if no exceptions, can be put into use.
(6) Parking procedure: close the exhaust valve, cut off the power supply, close the inlet, and when not in use for a long time, clean the inner passage of the pump and cut off the power supply.
2. Key points and methods of maintenance:
(1) Magnetic pump shaft fracture: The material used for the CQB magnetic pump pipeline pump shaft is 99% alumina ceramic. The main reason for the breakage of the pump shaft is the shaft breakage caused by the pump running and the dry grinding of the bearing. When disassembling the pump, we can see that the main way to prevent the pump from breaking is to avoid the pump running dry.
(2) Bearing damage: The bearings of the CQB magnetic pump are made of high-density carbon. If the pump is out of water or there are impurities in the pump, the bearing will be damaged. If the coaxiality between the inner and outer magnetic rotors of the cylindrical coupling is not guaranteed, the life of the bearing will also be directly affected.
(3) The magnetic pump can't hit the liquid: the failure of the magnetic pump to hit the liquid is the most common fault of the pump, and the reasons are various. First, we should check the suction pipe of the pump for leaks, whether the air in the suction pipe is exhausted, whether the liquid in the pump is sufficient, and whether there is any debris in the suction pipe. You should also check if the pump is reversed (especially after changing the motor or after the power line has been overhauled), and also if the pump's suction height is too high. If the above checks cannot be solved, the pump can be disassembled to check the centrifugal pump to see if the pump shaft is broken. It can also check whether the pumping ring and the stationary ring are in good condition, and the whole rotor can perform a small amount of axial movement. If the axial movement is difficult, check if the carbon bearing is too close to the pump shaft.
It is worth noting that the pump has been repaired several times and no problems can be found. It should be noted that the magnetic coupling works normally. The bearings, the inner magnetic rotor and the spacers generate heat during operation, which will increase the operating temperature, on the one hand, the power delivered, and on the other hand, the pump that transports the easily vaporized liquid will cause great trouble.
The power transmitted by the magnetic steel is a continuous decreasing curve with the increase of temperature. Generally, below the working limit temperature of the magnetic steel, the drop of the transmission capacity is reversible, and above the limit temperature is irreversible, that is, the magnetic steel is cooled. Afterwards, the lost ability to transmit can no longer be restored. Under special circumstances, when the magnetic coupling slips, the eddy heat in the spacer will increase sharply, and the temperature will rise sharply. If not treated in time, the magnetic steel will demagnetize and the magnetic coupling will be invalid.
Therefore, the magnetic pump should be designed with a reliable cooling system. For mediums that are not easily vaporized by chemical pumps, the cooling circulation system generally draws out the liquid flow from the impeller outlet or the pump outlet, and returns to the suction population through the bearing and the magnetic transmission part. For the easily vaporized medium, the heat exchanger should be added or the liquid flow should be led to Storage tanks outside the pump to avoid heat return to the population. For media with solid impurities or ferromagnetic impurities, filtration should be considered. For high temperature media, cooling should be considered to ensure that the magnetic coupling does not exceed the working limit temperature. When considering whether the speed is enough, first check whether the speed of the motor itself is normal. You can use the tachometer to measure. If the motor speed is normal, you can consider whether the magnetic coupling slips.
(4) Insufficient head: The cause of this failure is: there is air in the conveying medium, the impeller is damaged, the rotation speed is not enough, the specific gravity of the conveying liquid is too large, and the flow rate is too large.
(5) Insufficient flow: The main causes of insufficient flow are: impeller damage, insufficient speed, too high lift, and blockage of debris in the pipe.
(1) Since the cooling and lubrication of the magnetic pump bearing is based on the medium to be transported, it is absolutely forbidden to operate in an empty manner, and at the same time avoid the time-and-load operation caused by the power failure after the start of the work.
(2) If the solid medium is contained in the medium to be transported, a filter should be added to the pump inlet: if it contains ferromagnetic particles, a magnetic filter is required.
(3) The ambient temperature of the pump should be less than 40 °C during use, and the temperature rise of the motor should not exceed 75 °C.
(4) For the medium which is easy to precipitate and crystallize the transport liquid, it should be cleaned in time after use, and the liquid in the pump should be drained.
(5) The medium to be transported and its temperature shall be within the allowable range of the pump. The working temperature of the engineering plastic pump is <60 °C, the use temperature of the metal pump is <100 °C, the suction pressure is not more than 0.2 MPa, the maximum working pressure is 1.6 MPa, the density is not more than 1600 Kg/m3, and the viscosity is not more than 30×10-6 m2/S. A liquid containing hard particles and fibers.
(6) After 1000 hours of normal operation of the magnetic pump, the wear of the bearing and the end moving ring should be disassembled and the wearing parts that should not be reused should be replaced.