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A magnetic pump is composed of three components: a centrifugal pump, a magnetic drive unit, and a motor; it is also known as a magnetically driven pump. The working principle involves arranging n pairs of magnets (where n is an even number) in a systematic manner on the inner and outer magnetic rotors of the magnetic drive, so that the magnet groups form a complete and interconnected magnetic system. When the inner and outer poles are opposite to each other, that is, when the displacement angle Φ between the two poles is 0°, the magnetic energy of the magnetic system is at its lowest; when the poles align with each other, that is, when the displacement angle Φ between the two poles is 2π/n, the magnetic energy of the magnetic system is at its highest. Once the external force is removed, due to the mutual repulsion between the poles of the magnetic system, the magnetic force causes the magnet to return to a state with lower magnetic energy; as a result, the magnet moves and drives the magnetic rotor to rotate. The magnetic field can penetrate air gaps and non-magnetic materials, driving the internal magnetic rotor connected to the impeller to rotate synchronously, thereby achieving contactless power transmission and completely solving the leakage problem of pumps. (1) Slip magnetism phenomenon: When an overload occurs or the rotor gets stuck during the operation of a magnetic drive pump, the driving and driven components of the magnetic drive will automatically slip apart. At this point, the driven component does not rotate in sync with the driving component, resulting in demagnetization. Its characteristics are: ① A drop in pump outlet pressure. ②The motor current of the pump decreases. ③The temperature at the magnetic actuator rises rapidly. Prolonged operation causes the permanent magnets in the magnetic drive to experience eddy current losses and magnetic losses under the alternating magnetic field of the driving rotor, resulting in an increase in the temperature of these magnets. This leads to a loss of magnetic strength in the magnetic drive, and it also causes damage to the pump’s sliding bearings. (2) Reasons for slip magnetism in magnetic drive pumps: ① Originally, a tubular belt pump was used, with the pump’s outlet pipeline being DN100. After replacing the pump, the outlet pipeline is required to be DN65. However, due to the high difficulty of construction, the original DN100 pipeline is still used. When operating the pump in this way, it is difficult to control the opening degree of the valve at the pump outlet, which can easily cause the pump to operate under overload and result in slip magnetism. ②Since the density of liquefied gas changes significantly with temperature and pressure, when using magnetic pumps to transport liquefied gas, the operating conditions of the pump change greatly, increasing the likelihood of gas erosion within the pump and thus leading to magnetic slippage. ③The operators lack the necessary sense of responsibility; they are unable to monitor the liquid level in the storage tank in a timely manner during the operation of the magnetic pump, which leads to the pump running dry and causing magnetic slippage. ④The magnetic torque is designed to be too small. ⑤The magnetic sleeve of the pump’s magnetic coupling was not cleaned in a timely manner; there was a lot of debris attached to it, which reduced the magnetic strength and led to magnetic slippage during operation. Richter (Zhejiang) Technology