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The food processing industry is a rigorous and high-quality field, and ensuring food safety and quality is very important. Neodymium rod magnets are widely used in food processing as a key tool to remove possible ferromagnetic impurities such as metal fragments, iron filings, and magnetic particles. The following are the applications and advantages of neodymium rod magnets in the food processing industry:   Food production line   Neodymium rod magnets are usually installed in food production lines, in the flow of raw materials, or finished products. These production lines include bakeries, confectionery factories, meat processing plants, beverage production, etc. Neodymium rod magnets are able to capture metal impurities such as nails, screws, iron filings, etc., ensuring that these impurities do not enter the final product.   Raw material handling   In the food manufacturing process, raw materials may include iron ore, grains, spices, etc. Neodymium rod magnets are used to remove ferromagnetic impurities from these raw materials to ensure the composition and quality of the food.     One of the most important advantages of using neodymium rod magnets is ensuring food safety. By removing metal impurities, neodymium rod magnets help prevent metal fragments from entering food products, reducing potential hazards in food.     In addition to protecting food quality, neodymium rod magnets also help protect production equipment. Preventing metal impurities from entering equipment can reduce maintenance and repair costs and extend the life of equipment.  

The biggest risk in the use of permanent magnet motors is demagnetization caused by high temperature. As we all know, the key component of permanent magnet motors is neodymium magnet, and neodymium magnet is most afraid of high temperature. It will gradually demagnetize under high temperature for a long time. The higher the temperature, the greater the risk of demagnetization.   Once a permanent magnet motor loses its magnetism, you basically have no choice but to replace the motor, and the cost of repair is huge. How do you determine whether a permanent magnet motor has lost its magnetism?   1. When the machine starts running, the current is normal. After a period of time, the current becomes larger. After a long time, the inverter will be reported to be overloaded.   First, you need to make sure that the inverter selected by the air compressor manufacturer is correct, and then confirm whether the parameters in the inverter have been changed. If there are no problems with both, you need to judge by back electromotive force, disconnect the head from the motor, perform no-load identification, and run no-load to the rated frequency. At this time, the output voltage is the back electromotive force. If it is lower than the back electromotive force on the motor nameplate by more than 50V, it can be determined that the motor is demagnetized.     2. After demagnetization, the running current of permanent magnet motor will generally exceed the rated value.   Those situations where overload is reported only at low or high speed or occasionally reported, are generally not caused by demagnetization.   3. It takes a certain amount of time for a permanent magnet motor to demagnetize, sometimes several months or even one or two years.   If the manufacturer selects the wrong model and causes current overload, it does not belong to motor demagnetization.   An important indicator of permanent magnet motor performance is the high temperature resistance level. If the temperature resistance level is exceeded, the magnetic flux density will drop sharply. The high temperature resistance level can be divided into: N series, resistant to more than 80℃; H series, resistant to 120℃; SH series, resistant to more than 150℃. The motor's cooling fan is abnormal, causing the motor to overheat. The motor is not equipped with a temperature protection device. Ambient temperature is too high. Improper motor design.

Demagnetization may be caused by a variety of factors, including: high temperature, physical shock or long-term time-induced natural decline in magnetism.   Specifically, when a permanent magnet is subjected to high temperatures, the magnetic dipoles inside it lose their ordered arrangement, causing the magnetism to weaken or disappear.   For example, the Curie temperature of permanent magnets is relatively low, and once their maximum operating temperature is exceeded, the magnets will gradually demagnetize.     In addition, physical shock may also cause demagnetization of permanent magnets because the shock may change the arrangement of magnetic dipoles, destroying the magnetic domain structure and thus affecting the magnetic properties.   Over time, even if a permanent magnet is not subjected to significant physical shock or high temperatures, its magnetism may naturally decay, because the arrangement of the magnetic dipoles may gradually become disordered, resulting in a weakening of the magnetism.   This depends on the external conditions the magnet encounters and the properties of the permanent magnet itself.  

The magnetic arc industry is set to thrive in the coming years, driven by advances in the design of permanent magnet motors and the growing demand for neodymium magnets from a wide range of industries.    Magnet Arcs in Motor Design   Permanent magnet motors rely on arc magnets to create consistent magnetic fields in rotors, enabling smoother and more efficient operation. With the increasing adoption of electric vehicles and industrial automation, the demand for high-quality arc magnets is growing. The shift toward renewable energy systems, including wind turbines, is also increasing this demand.   Wholesale Supply and Customization   Wholesale markets for neodymium magnets, including neodymium arc, are expanding rapidly. All manufacturers require magnets that meet high quality and dimensional standards for different uses. Companies like Huajin are equipped to provide customized solutions, addressing specific needs in motor production, medical equipment, and consumer electronics.     Key Applications Driving Growth   Electric Vehicles: Arc magnets are integral to the lightweight, high-performance motors that power modern EVs. Renewable Energy: Permanent magnet generators in wind turbines utilize arc magnets for consistent energy conversion. Industrial Tools: Precision tools and machinery benefit from the reliable strength of neodymium arc magnets.   For businesses seeking dependable supply and innovation, Nanjing Huajin Magnet Co., Ltd. offers unmatched expertise in the production of high-performance neodymium magnets. With a focus on customization, quality, and scalability, Huajin is poised to support the evolving demands of this dynamic industry.     For more details about our products and solutions, explore our offerings on neodymium magnets and their applications. Let's shape the future of magnetic technology together!          

As a high-performance magnetic material in modern industry, NdFeB permanent magnets promote the progress of contemporary technology and society and are widely used in various fields. How to judge the advantages of permanent magnet products: 1. Magnetic properties; 2. The size of the magnet; 3. Surface coating.   1. Magnetic properties：First, the key to the decision is to control the magnetic properties of the raw materials during the production process.   Raw material manufacturers can choose mid-range or low-grade sintered NdFeB according to business needs. In accordance with the national standards for purchasing raw materials, our company only sells high-grade NdFeB.   The quality of the production process also determines the performance of the magnet.   Quality control during production is important.     2. Magnet shape, size and tolerance: Utilize various shapes of NdFeB magnets, such as round, special-shaped, square, arc-shaped, trapezoidal. Different sizes of materials are processed by different machine tools to cut rough materials, the technology and machine operator determine the accuracy of the product.   3. Surface coating treatment: The coating quality of the surface coating, zinc, nickel, nickel-copper-nickel electroplating copper and gold and other electroplating processes. The product can be electroplated according to customer requirements.   The quality of NdFeB products can be summarized as a good grasp of performance, dimensional tolerance control, and appearance inspection and evaluation of the coating. Tests such as the Gaussian surface of the magnetic flux of the magnet; dimensional tolerance, which can be measured with a vernier caliper; coating, coating color and brightness and coating bonding strength, and the appearance of the magnet surface can be observed to be smooth, with or without spots, and with or without edges and corners, to evaluate the quality of the product.  

When we want to clearly state the purchase demand for a neodymium magnet, there are several key points that need to be clarified: performance requirements, shape and size, magnetization direction, and surface treatment requirements. The purchaser is advised to provide drawings of the magnet. Below we take NdFeB permanent magnets as an example to explain in detail.   1. Performance requirements:   That is, the requirements for the grade of magnets. There are many suppliers in the magnetic material industry, and each neodymium magnet factory has different definitions and performance ranges for the same grade. When communicating the brand, it is recommended that both the supply and demand parties clarify the remanence Br and intrinsic coercivity Hcj of the corresponding brand, so that it is not easy to cause deviations. (If the purchaser is not clear about the product brand, then some auxiliary judgment indicators such as surface magnetism, tension, magnetic flux/magnetic moment, etc.) We usually offer a neodymium magnet grades chart in our catalog.   In addition, according to factors such as the working environment of the magnet, indicators such as remanence and coercivity temperature coefficient can be further clarified. If there are clear requirements for indicators such as magnetic flux, the detection equipment and detection method should be agreed as the judgment standard.     2. Shape, size and magnetization direction:   When describing the purchasing requirements, the neodymium magnets shapes and size requirements of the magnet must be clear, such as 6.0mm (+0.05/-0.05). For simple products, provide basic length, width and height dimensions and tolerances; for magnets with complex shapes, the contour and other angle requirements need to be provided more clearly. It is recommended to provide suppliers with clear drawings.   In addition, the magnet also needs to mark the product's orientation direction (NS pole) and magnetization method (single pole or multi-pole charging), as well as the magnetization angle, etc.   3. Surface treatment requirements:   The purchaser needs to specify the surface treatment method of the magnet, including coating method (electroplating, chemical plating, electrophoresis, vapor deposition, etc.), coating material (zinc, nickel, copper, aluminum, epoxy resin, etc.), and coating thickness.   If there are requirements for salt spray or other tests, the setting of the test conditions, the placement time, and the judgment criteria after the test need to be agreed upon.   4. Other requirements:   Such as: appearance requirements, other testing requirements (such as aging tests, etc.), packaging requirements, transportation requirements, etc.

When choosing a magnetic filter to fit the different shapes of injection molding machines and extruder hoppers, there are several key factors to consider:   1. Hopper shape and size: First, the shape and size of the magnetic filter should match the hopper of the injection molding machine or extruder. For hoppers of different shapes, such as round, square, or other special shapes, the design of the magnetic filter also needs to be adjusted accordingly to ensure that it can fit tightly on the hopper and effectively capture iron impurities.   2. Magnetic strength: The magnetic strength of the magnetic filter is an important consideration when choosing. The magnetic strength should be strong enough to adsorb and capture iron impurities in the hopper, but not too strong to avoid damage to the hopper or the magnetic frame itself. Therefore, when choosing a magnetic filter, it is necessary to determine the appropriate magnetic strength based on the type and amount of iron impurities that may be present in the hopper. All the magnetic filters produced by our factory are made of neodymium magnet material, with magnetic field strength ranging from 8000-14000GS, which can be applied to different needs.   3. Use environment: The working environment of the injection molding machine and extruder may be different, such as temperature, humidity, and dust. Therefore, when choosing a magnetic filter, it is necessary to consider whether it can work properly in this environment. For example, for high temperature or high humidity environments, you should choose a magnetic stand that is resistant to high temperatures and waterproof and moisture-proof!   4. Maintenance and cleaning: The magnetic filter may require regular maintenance and cleaning during use. Therefore, when choosing a magnetic filter, the convenience of its maintenance and cleaning should be considered. For example, some magnetic filters may be designed to be easy to disassemble and clean, which will help reduce maintenance time and costs.   In summary, when choosing a magnetic filter with different hopper shapes for injection molding machines and extruders, it is necessary to consider multiple factors such as hopper shape and size, magnetic strength, use environment, and convenience of maintenance and cleaning.    Communicating with a permanent magnet supplier when choosing a magnetic rack is recommended to ensure that the selected magnetic filter can meet the actual production needs.  

Multi-pole magnetic ring is a kind of ring magnet widely used in the field of motors. The characteristic of multi-pole magnetic ring is that there are many magnetic poles on one magnet, which is usually achieved by using professional magnetizing equipment. Through technological innovation, the stability and assembly problems of the user end are solved. It has become the first choice for servo motors such as power tools and EPS power steering motors.   Multi-pole magnetic rings can be divided into neodymium iron boron multi-pole magnet rings, ferrite multi-pole magnetic rings, rubber magnetic multi-pole magnet rings, and samarium cobalt multi-pole magnet rings according to different materials. Among them, the first three are more common on the market.     Among the above multi-pole magnetic ring materials, the one with the strongest magnetic force is the multi-pole magnetic ring made of NdFeB magnet material. NdFeB magnet is known as the "king of magnets" among magnets. It has a very high remanence and is mainly used in high-performance permanent magnet motors and sensors. In addition, according to different processes, NdFeB multi-pole magnetic rings are divided into sintered NdFeB multi-pole rings and bonded NdFeB multi-pole magnetic rings. The cost of rubber magnetic multi-pole rings and ferrite multi-pole magnetic rings is relatively low, but the magnetic force will be relatively weak.     The most widely used products at present are circular magnetic grids, water pump motors, sweepers, etc. The multi-pole magnetic ring made of samarium cobalt material is the most temperature-resistant multi-pole magnetic ring. The maximum temperature of this material can reach 350 degrees. It is the best magnet used in high-temperature environments. As for the number of poles of the multi-pole magnetic ring, it is also customized according to customer requirements. The highest number of magnetization levels can reach hundreds of poles or even more.   The application of multi-pole magnetic rings is not limited to high-performance permanent magnet motors and sensors, but also includes automobiles, CNC machine tools, household appliances, computers, robots and other fields, showing its important role in the development of automation, precision and permanent magnet motor design, manufacturing technology and control technology.    

Air transportation has certain particularities. To ensure safety, both people and goods need to undergo security checks before boarding. If you carry magnetic materials, such as NdFeB magnets, or if customers are in a hurry to get the goods and hope that the manufacturer will ship them by air, can we bring the magnets on board?   Since weak stray magnetic fields can interfere with the aircraft's navigation system and control signals, the International Air Transport Association (IATA) has classified magnetic cargo as Class 9 dangerous goods, which must be restricted during transportation. Therefore, some air cargo with magnetic materials now needs to undergo magnetic testing to ensure the normal flight of the aircraft. Magnetic materials, audio materials, and other instruments with magnetic accessories must undergo magnetic testing.     Airlines or logistics companies that transport magnetic materials will force customers to undergo magnetic testing and issue an "Air Transport Conditions Identification Report" to ensure the normal flight of the aircraft. Air transport identification can generally only be issued by a qualified professional identification company recognized by the country's civil aviation administration, and it is generally necessary to send samples to the identification company for professional testing before issuing an identification report. If it is inconvenient to send samples, the identification company's professionals will conduct on-site testing and then issue an identification report. The validity period of the identification report is generally for the current year, and it is generally necessary to re-do it after the New Year.   During magnetic testing, customers are required to pack the goods according to air transport requirements. The testing will not damage the packaging of the goods. In principle, the goods will not be unpacked for testing, but only the stray magnetic field of the six sides of each piece of goods will be tested. If the goods fail the magnetic test, special attention should be paid. First, with the consent of the customer, the magnetic inspection staff will unpack the goods for inspection, and then make relevant reasonable suggestions based on the specific situation. If the shielding can meet the requirements of air transportation, the goods will be shielded according to the customer's entrustment, and relevant fees will be charged.  

The internal structure of the neodymium magnetic bar is not just composed of a whole magnet. In fact, the neodymium magnetic bar consists of an internal magnetic core and an external cladding. The magnetic core is the core part of the magnetic bar, usually composed of a cylindrical magnetic block and a conductive magnetic sheet. These magnetic blocks and conductive magnetic sheets work together to generate a strong magnetic field, thereby achieving the adsorption of ferromagnetic materials.   The external cladding plays a role in protecting the magnetic core and enhancing the stability of the magnetic bar structure. At the same time, a good magnetic bar equipment should have a uniform spatial distribution of magnetic induction lines, and the distribution of magnetic induction points should fill the entire magnetic bar as much as possible to ensure that it can provide stable adsorption at all positions.     Therefore, although the magnetic bar contains magnetic components inside, its structure is far more complex than a single magnet, and is the result of the coordinated work of multiple components. This design enables the magnetic bar to efficiently and accurately remove ferromagnetic impurities and improve product quality in the fields of chemical, food, and waste recycling.   As a professional neodymium magnets manufacturer, Huajin provides bulk magnetic rods with high gauss magnet strength that can be customized according to customer requirements.  

Neodymium ndfeb materials have poor thermal stability, and their high temperature coefficient can easily cause irreversible demagnetization (also known as demagnetization) when permanent magnet motors are running.   On the one hand, the eddy current of permanent magnet motors generates heat on the surface of permanent magnets, and the heat dissipation conditions inside the motor are poor, which exceeds the working temperature of permanent magnets, causing permanent magnet demagnetization. Therefore, the temperature stability of permanent magnets is crucial to motor applications.   On the other hand, the unreasonable design of the working point of the permanent magnet motor magnetic circuit is also prone to irreversible demagnetization. When the motor encounters a large demagnetization during starting, reversing and stalling, the working point of NdFeB may drop below the inflection point of the demagnetization curve, causing irreversible demagnetization. Therefore, the working point of the permanent magnet motor magnetic circuit should be designed to be higher than the inflection point of the NdFeB material. When the motor stops running, the residual magnetic induction intensity Br of the permanent magnet material remains basically unchanged.   The design of permanent magnet motors must also understand the actual operating environment of the motor and take necessary measures in assembly to ensure that it is in a stable state without demagnetization at high temperatures. The SH grade NdFeB magnets used in motors that meet the standard requirements cannot guarantee that the motor will not lose magnetism during operation. Only by increasing the intrinsic coercive force and Curie temperature of the NdFeB magnets can the irreversible magnetic loss of the NdFeB magnets be reduced and the temperature stability of the permanent magnets be improved, thereby extending the service life of the permanent magnet motor.   

In daily life, magnets are a very common thing. From various special electronic devices to daily teaching aids and toys, magnets can often be seen.   We know that the main component of magnets is ferroferric oxide. An ordinary small magnet is made of black ferroferric oxide. However, due to the nature of ferroferric oxide itself, its attraction to iron objects is not too strong, and its magnetism will gradually weaken over time. In this case, how can we make a magnet with stronger attraction and less prone to decay? Under this premise, neodymium iron boron magnets came into being.     This kind of magnet with a shiny surface after anti-corrosion treatment is a neodymium boron magnets, and its chemical formula is Nd2Fe14B. The most commonly used neodymium iron boron magnet is made of neodymium, iron, and boron at high temperature sintering, and is the strongest artificial magnet to date. If the core element of traditional ferroferric oxide is iron, then the reason why neodymium iron boron magnets have such strong magnetism is the role of neodymium. The pieces of metal in the picture below are neodymium:     Neodymium is the fourth element of the lanthanide family of rare earth elements. Like iron, cobalt, nickel and the aforementioned gadolinium, it can also be attracted by magnets. In addition, neodymium is the most active of the lanthanide elements, so it is easily oxidized like iron, which is why there is a coating on the surface of the NdFeB magnet. If neodymium is used to enhance magnetism, then the role of boron should not be underestimated.    In the periodic table, boron is located to the left of carbon, so boron chemistry similar to carbon-centered organic chemistry has recently emerged. In NdFeB magnets, boron is the mediator between neodymium and iron. Boron greatly expands the maximum magnetism that a substance can produce while ensuring the stability of its molecular structure, making the neodymium magnetic properties of the entire magnet extremely high, and even allowing it to attract objects equivalent to 640 times its own weight.