Exploring the path of magnetic levitation magnetic pump technology

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In 2022, a new wave of the pandemic struck suddenly, putting the economy under severe strain and forcing many companies to face enormous pressure. However, Richter managed to overcome these challenges and achieved significant year-on-year increases in production and sales. Key products such as magnetic pumps, shielded pumps, pneumatic diaphragm pumps, and chemical pumps led in terms of sales volume, earning high praise from customers everywhere. Results belong to the past; innovation wins the future. Reichert is well aware that only by continuously innovating and creating new solutions to meet the demands of the new era in the market can one keep up with the leaders in the industry. Therefore, in 2022, after thorough design evaluations, extensive market research, and production tests, Richt decided to embark on the design, development, and production of a new generation (fifth generation) of magnetic pump – magnetic levitation bearing magnetic pumps. By daring to be pioneers and taking the lead of the times, it actively explored the path for developing magnetic levitation magnetic pumps, achieving breakthroughs and success in this process. In recent years, China has made unprecedented progress in the research and development of maglev trains. Tests of these trains have been successful, with speeds reaching nearly 600 km/h. Maglev technology was successfully tested on the \"Zhonghua 6\" lightweight suspension maglev technology demonstration vehicle. The first permanent-magnet maglev line with a speed of up to 536 kilometers per hour is set to be built in Dalian, indicating that maglev technology has shifted from fields such as military and aerospace to industrial and civilian applications – the dream of maglev technology has now become a reality. / A brief introduction to magnetic levitation / Currently, there are three types of magnetic levitation in the world: the first is the conductive magnetic levitation type, represented by Germany ； The second is superconducting electromagnetic levitation, represented by Japan. Both types of magnetic levitation require electricity to generate the necessary levitation force ； The third type is China’s permanent magnet levitation system, which utilizes special permanent magnet materials and does not require any other form of power support. Since the vehicle body has no contact with the tracks at all, there is no friction, so there is no shaking or bouncing, and no noise is produced either. Only when the speed reaches a certain level will passengers hear some sounds resulting from air friction. Magnetic motors offer high traction, low noise, and excellent environmental benefits. Compared with the synchronous linear motor drive technology commonly used in foreign maglev systems, the magnetomotor drive technology can save around 50% in energy consumption, as well as reducing construction costs by 20 to 40 million yuan per kilometer. It is evident that our country has surpassed international advanced levels in the field of maglev trains, achieving a leading position globally. Profile: Professor Li Guokun has been engaged in the research and development of magnetohydrodynamics theory and high-tech technologies for over 40 years; in the past 20 years or so, he has focused on the development of rare earth magnetic circuits and rare earth magnetic devices. He has made outstanding and creative contributions to high-tech fields such as magnetic circuits, magnetic drive, magnetic sealing, magnetic levitation, magnetic pumps, magnetic mineral processing, magnetic iron removal, magnetic level gauges, and energy-saving large electromagnets. In 1979, the theory of \"push-pull magnetic circuit\" was invented, remaining at the international leading level and being known as \"Li’s push-pull theory\". Won the **Third Prize for Invention, and was awarded a First-Class Merit by the Ministry of Aeronautics. This invention has been widely used in various high-tech fields such as satellites and environmental protection, as well as in various industrial sectors for civilian use including the petrochemical industry, vacuum technology, and electromechanical systems. Magnetic levitation magnetic pump represents a new trend in the pump and valve industry, and of course it has encountered many technical challenges. Despite numerous difficulties, the continuous support of authorities and professionals provided the Reichites with endless motivation and confidence. We will make unremitting efforts to devote our energy to the research, development, and design of magnetic levitation magnetic pumps. Although the task is arduous and the path is long, it is imperative to carry it out... - Design principle - Utilize the force of a magnetic field to lift the rotating shaft in a contactless manner, thereby bringing about a technological revolution in the support systems of traditional magnetic pumps. As is well known, the sliding bearings on magnetic pumps that support the impeller and rotor, as well as the thrust rings that bear axial forces, rely on the medium being pumped for lubrication and cooling. If there is a failure in the circulation system, the pump will be damaged quickly, and in severe cases, serious accidents may occur. A magnetic levitation bearing is a new type of bearing that uses electromagnetic forces to keep the rotor suspended stably, with its axis position being controllable by a control system. In simple terms, it involves suspending the pump shaft so that there is no contact or frictional wear, and no lubrication is required. This allows for higher rotation speeds, which in turn greatly improves the efficiency of the pump, reduces energy consumption, and extends its service life. It offers advantages that other magnetic pumps do not possess, thereby significantly enhancing the customers’ production efficiency and output capacity. / Basic principle / A magnetic levitation bearing is a bearing that uses magnetic field forces to levitate the rotating shaft in a contactless manner. Contactless operation can avoid mechanical wear, reduce energy consumption, and lower noise; as a result, it offers advantages such as maintenance-free operation, high rotational speeds, high precision, and good dynamic performance. Its power consumption is approximately 1/10 to 1/100 of that of conventional sliding bearings. The position of the shaft can be controlled through an electronic control system, and the damping and stiffness of the bearings can be adjusted, thereby ensuring good dynamic stability for the shaft sleeve. Based on the suspension method, magnetic levitation bearings can be divided into passive magnetic levitation bearings (also known as passive magnetic suspension bearings) and active magnetic levitation bearings (also known as active magnetic suspension bearings). Bearings that use permanent magnets or superconductors alone for suspension are called passive magnetic levitation bearings ； Bearings that are suspended by electromagnetic forces generated by a power source are called active magnetic bearings. Permanent magnet magnetic suspension bearings have a simple structure, low cost, and reliable performance, but they have low stiffness, are unable to provide stability in both axial and radial directions, and result in one coordinate being unstable ； Schematic diagram of the operation and structure of passive magnetic bearings.jpg Active magnetic bearings have advantages such as high stiffness and stable operation; however, they must be equipped with a control system. Therefore, the combined use of permanent magnet magnetic bearings and active magnetic bearing pumps is a valuable design solution for magnetic levitation magnetic pumps*. / Structural design / In the design of conventional magnetic pumps, sliding bearings and shaft sleeves are used to support the weight of the shaft sleeve, impeller, and pump shaft. Thrust rings are employed to bear the axial thrust exerted by the impeller. Therefore, sliding bearings, shaft sleeves, and thrust rings are considered replaceable components and are key elements determining the service life of magnetic pumps. For a long time, although designers have continuously researched, improved, and optimized the materials used for these friction pair combinations, mechanical friction that occurs during high-speed operation remains an inevitable issue regardless of the materials chosen, thereby limiting the service life of the pump. Therefore, only when such friction is absent can the service life of magnetic pump be greatly extended. A magnetic levitation magnetic pump is a new type of magnetic pump that utilizes contactless support based on the principles of magnetic levitation. With the advent of this type of pump, the aforementioned technical problems are resolved. Magnetic levitation bearing magnetic pump mechanism diagram.jpg / Electromagnetic bearing / The electromagnetic bearing uses a repulsive-type design; its body is composed of ring-shaped ferromagnetic laminations, and an electromagnetic force is generated when coils wound around its circumference are energized. Displacement sensors are installed on its inner circular side wall to detect the deviation signal of the shaft sleeve ； An interface is provided on the outer circular surface; the detected deviation signals of the shaft sleeve are sent to an external control device via this interface. The power amplifier then controls the current in the magnets, thereby causing changes in the electromagnetic force that keeps the shaft sleeve suspended at a specified position. . Considering the corrosiveness of the conveyed medium, after assembly, the electromagnetic bearing is encased in a stainless steel sheath. The outer surface of this sheath features a wedge-shaped groove that secures the electromagnetic bearing to the bearing housing of the magnetic drive pump. / Permanent magnet sleeve / The permanent magnet sleeve is made of neodymium-iron-boron, a strong magnetic permanent material, and is radially magnetized. It is mounted on a stainless steel permanent magnet sleeve base, and after assembly its outer surface is enclosed using a cover. This component is mounted on the pump shaft and transmits power through a key located on the pump shaft, enabling it to rotate synchronously with the pump shaft. The assembled electromagnetic bearing and permanent magnet sleeve have a radial clearance of 1–1.5 mm. Based on the principle of like-charge repulsion, the repulsive force generated by their surface magnetic fields is used to suspend the high-speed rotating pump shaft in a predetermined position, with monitoring being carried out via an external controller. The circulation system inside the pump is used solely to remove the eddy current heat from the metal isolation sleeve. Magnetic levitation bushing, bearing assembly diagram.jpg / Permanent magnet thrust ring / In magnetic pump systems, thrust rings are used in traditional designs to counteract the axial force generated by the rotating impeller. The thrust ring on the magnetic levitation magnetic pump is of a permanent magnet thrust ring design; it consists of neodymium-iron-boron, a strong permanent magnetic material, which is radially magnetized and then mounted on a stainless steel base. After assembly, its surface is further enclosed as a whole by an annular stainless steel sleeve. There is a gap of 1.5 mm between the permanent magnet thrust ring and the electromagnetic bearing. Therefore, the combination of permanent magnet magnetic levitation bearings and active magnetic levitation bearings with pumps, along with the scientific and rational assembly of high-end permanent magnet materials, represents the ideal approach for the development of magnetic levitation magnetic pump systems. - Looking forward to the future – it will surely lead the way in developing new trends for magnetic pump technology and open up new horizons. Adhering to conventions only results in staying in place, while innovation enables progress in keeping pace with the times. The Richters understood this principle deeply, so they committed themselves wholeheartedly to the research, development, and production of magnetic levitation magnetic pumps, striving to be pioneers of the times. It is believed that the introduction of the Reichert magnetic levitation magnetic pump will surely set a new trend for magnetic pumps and open up new possibilities.