What are the startup procedures and precautions for magnetic pump operation?

The procedure is the same as that for centrifugal pumps. The things to note are that, according to the requirements of the pump, it is necessary to ensure proper evacuation and to keep the temperature from rising too high, as this can easily lead to demagnetization.

The inlet pipeline should be equipped with a filter, or a magnetic filter; it is absolutely not allowed to operate in a dry condition or with the outlet valve closed. The power of the motor selected must match the shaft power of the pump. Magnetic bearings should be replaced promptly when they wear out, to prevent the isolation sleeve from being worn through. Magnetic pumps should be fitted with safety monitoring devices such as those for temperature, differential pressure, and vibration. During operation, attention should be paid to the liquid level in the inlet tank to avoid cavitation or vacuum formation.

1. Idle operation is prohibited. 2. If the medium contains solid particles, a filter should be installed before the pump. 3. The operating temperature of the pump must not exceed 40 degrees, and the temperature rise of the motor must not exceed 75 degrees. 4. After approximately 500 hours of operation, the wear of the bearings and the axial moving rings should be checked; if necessary, the bearings and axial moving rings should be replaced promptly

As a supplementary note, during maintenance, the replacement criteria are: the clearance between the bearing and the shaft sleeve should be greater than 0.5–1 mm, and the axial movement of the impeller should be 1.5–2 mm

Filling and venting: To ensure the magnetic pump operates properly, it is necessary to fill it thoroughly and vent it as well. Fully open the valves in the pump inlet and return pipelines, as well as the outlet pipeline, to allow the magnetic pump to exhaust air automatically. When transporting liquefied gas or volatile liquids, exhaust the air several times until it is ensured that the pump is filled with liquid. When transporting low-temperature liquids, it is necessary to wait until the flow-through components of the pump have cooled down to the temperature of the liquid before starting the pump, so as to ensure that the fluid reaches all parts of the pump ； Starting procedure: The model of the magnetic coupling is selected based on the drive motor in order to ensure proper operation. However, if it is started under inappropriate conditions (for example, if the motor power is too high or the outlet valve is opened too wide), the maximum torque of the magnetic coupling will be exceeded, preventing the pump from functioning properly. Therefore, it is important to ensure that it is started correctly. a. Fully open the valve of the inlet pipeline ； b. Close the valve on the outlet pipeline (if there is a throttling bypass, the bypass must be fully open) ； c. Start the motor ； d. Slowly open the valve in the outlet pipeline ； e. Adjust the outlet valve until the normal operating pressure is reached ； f. To ensure the pump operates properly, it should be operated within its allowable range. g. Magnetic pumps must under no circumstances operate under dry friction conditions or with the valves in the outlet pipeline closed, as this will cause damage to the sliding bearings. h. It must operate in synchronization with the motor; if the pump fails (with very low head), it indicates that the maximum torque of the magnetic coupling has been exceeded, and long-term operation under unsuitable conditions should be avoided. i. Under normal operating conditions, if vibration, excessive noise, and increased power consumption occur, it indicates that the bearings are worn out (due to insufficient lubrication) and should be inspected immediately. j. The failure of a magnetic coupling does not mean that the permanent magnets are damaged. However, operating for a long time in a failed state, due to its low speed and poor lubrication of the sliding bearings, will lead to damage to those bearings. k. When left unused for an extended period, crystallization may occur in the liquid being transported; therefore, hot water at the pump inlet should be used to flush the pump.

Magnetic pump – running idle or dry. It is recommended to install an anti-idle protection device for the pump, which will shut it down automatically within 2 seconds when idling, thus protecting the pump from damage. Electronic sample available at: http://www.dnpump.com/PicUp/200910162202501.pdf If you want less maintenance, opt for a built-in anti-idle protection device – it saves trouble!