How to enhance magnetism if permanent magnet size is the same?

Some customers might ask how to strengthen magnetism of permanent magnets in the same size. They prefer not to enlarge size. China Rare Earth Magnet Limited would like to talk about this.

For customer who has no specific requirement for size of magnet, we could just enlarge the size, thicken the magnet, which is the most effective way. However some might have strict demands of specification and do not want to change the size. In such case, we could try magnet in a higher grade to strengthen the magnetism and give customer what they want. Another solution is that add an iron sheet to one side of the magnet. Thus, its magnetism would be enhanced. That is also how single-side magnet works.

Before arranging mass production, customer could purchase samples to make sure if the requirement for magnetism is met. If not, customer should keep trying permanent magnet in a higher grade until customer is satisfied with the magnetism.

Above are some tips on magnetism strengthening for magnet in the same size. Feel free to contact us if there if any question about above content.

Tags: permanent magnet

How can permanent magnets be brought on board and meet air transport standards?

We often see the question in the major forums and Tieba how strong magnets can bring on the plane, what measures need to be done. What are the packaging requirements? Today, we strong permanent magnet manufacturer- China Rare Earth Magnet Limited would like to talk to you in detail.

The International Air Transport Association (IATA) lists magnetic cargo as a category 9 hazard, which must be restricted at the time of shipment, because a weak stray magnetic field has the interference of the aircraft's navigation system and control signals. So now some of the cargo with magnetic substances in the air needs to be magnetically tested in order to ensure the normal flight of the aircraft. Magnetic testing is carried out on magnetic materials, acoustic materials and other instruments containing magnetic accessories.

Magnet Air Transport Standard. According to the relevant provisions of IATA902, if the maximum magnetic field strength measured at 2.1m from the measured object does not exceed 0.159A/m (200nT, that is equal to 2mGs =0.002Gs), the item is not restricted as a magnetic substance and can be treated as a general cargo.
If the maximum magnetic field strength measured at 2.1m from the measured object exceeds 0.159A/m, but the strength of any magnetic field at 4.6m from the surface of the measured item is less than 0.418A/m, the goods can be transported as dangerous goods.If the strength of any magnetic field at 4.6m above the surface of the measured item is greater than 0.418A/m, the item is strictly prohibited for air transport.

How can the cargo meet the air transport standard?
In order to meet the above air transport requirements, degaussing treatment is needed. Although called demagnetization, it is not to demagnetize the magnet. Instead, it is through special shielding packaging, so that the external display of the magnetic package to meet the required aviation safety transport requirements. Shielded packaging will generally use high magnetic materials, such as cold-rolled plate, galvanized plate, if the size of permanent magnetic material is big, it will need multi-layers package. The conductivity of high magnetic conducting material is very high. According to the Faraday electric cage principle, magnetic field will circulate mainly in the box after package, so there is little magnetism leaking out. Cartons or wooden box packaging will be used after shielding package.

Packaging matters for magnets transported by air should be concerned.
1, Magnetron, illuminometer and other instruments, devices, the opposite magnetic pole must be relatively placed.
2, Permanent magnets must do the shielding package, in order to prevent the magnetic field from causing the deviation of the compass instrument.

3, Ensure that before the shipment, the field strength measured from the surface of the package 4.6 meters (15 feet) is not more than 0.418A/m (0. 00525 Gauss).
4, It is recommended a large cargo should use wooden box packaging.

Magnetic detection. Airlines or logistics companies that carry magnetic materials require customers to do magnetic testing to ensure the normal flight of the aircraft. On-site testing by qualified professional identification company professionals, and then issued a appraisal report. Magnetic testing needs customers to pack goods according to air transport requirements. Detection will not destroy the packaging of goods. In principle, the test is not open to the goods, but the six sides of each piece of goods for stray magnetic field detection. If the goods magnetic test is not qualified, they will be returned to repacking, and then re-do magnetic testing. Magnetic inspection fees also need to be re-charged.

If you have any other questions about magnets, please feel free to contact us.

Tags: permanent magnets

Permanent Magnet Used in Motor of Windscreen wiper 20191031

Windscreen wiper is mainly used to clean the rain or snow on windshield and make sure range of vision of driver is clear in rainy or snowy days.

Driven by electric motor, windscreen wiper is consisted of retarder, wiper switch, linkage and blade.
The left and right blades of the windscreen wiper are pressed on the windscreen by wiper’s arms. Electric motor turns the retarder and drives the linkage to reciprocate which would put the arms of wiper and blade in motion. Thus, the windshield is cleaned.

Electric motor (electric motor of wiper) can be classified according to their magnetic field. There are permanent magnet motor and electromagnetic motor.
Structure of permanent magnet motor used in windscreen wiper

Permanent magnet motor has long been in common usage as its magnetic pole is permanent magnet, normally is ferrite magnet. Small, light and simple and cheap, those are advantages of permanent magnet motor. So this kind of motor is widely used in cars.

Tags: permanent magnet, motor magnet

What kinds of rotor permanent magnets are inside servo motors?

What are the internal rotors of servo motors?
The internal rotors of servo motors are permanent magnets. The so called permanent magnets refer to those magnets that have unchanged magnetic poles and magnetic field strength. Servo motors mainly used arc magnets, just as below pictures:

Here is some information of servo motors magnets.
1、Do the rotor magnets of servo motors need adhesive?
The rotor magnets must need adhesive. There are many types of adhesive, such as KR series of high temperature resistant adhesive, AB adhesive and so on.
2、Why can't we use electromagnets to replace permanent magnets as the rotors?
Some netizens might reply that the electricity needs money, and in a finite electricity and space, the magnetic fields that can be generated are not necessarily stronger than the permanent magnets.
3、What magnets are the hard disc head servo motors use?
The hard disc head servo motors are voice coli motors, which are the same as general permanent magnet synchronous motors; the magnetic material is rare earth permanent magnets NdFeB.

The servo driver controls the U/V/W three-phase electricity forming an electromagnetic field, and the rotor rotates under the action of this magnetic field. At the same time, motor built-in encoder feedback signal to the driver, the driver will compare the target value according to the feedback value, so as to adjust the angle of the rotor rotation. The precision of servo motor depends on the precision of encoder (line number).
PS: When the servo motor is working, it should avoid the entering of oil and water. Because the servo motor is not the fully waterproof equipment, it is not suitable to put it in the water or oil environment. While connecting to the reduction gear, users should pay attention to prevent the oil of reduction gear from entering the motor, as well as preventing cables from oil and water.

Professionalism makes the future, success accompanies you and us. Our company is specialized in manufacturing hall sensor magnets, motor permanent magnets, irregularity magnets, multi-poles injection magnet rings, etc. If you have any demand for magnets, welcome to contact our company—China Rare Earth Magnet Limited.

Tags: permanent magnet, motor magnets

what are one-side permanent magnets?

Are you wondering what one-side magnet is? Here to introduce the one-side magnets.

The Introduction of One-side Magnets
Permanent Magnets have two poles, but in some specific working positions a single-pole magnet is needed. So we need to encase one side of magnet by metal plates, in order to shield the magnetism of that side. And strengthen the magnetism of the other side through the refraction of metal plates. These magnets are collectively known as one-sided magnets. But actually, the real one-sided magnets don’t exist.

The Material of One-side Magnets
The material used for one-side magnets is neodymium rare earth magnets. Most of the one side magnets are disc shapes.

The Application of One-side Permanent Magnet
1、One-side magnets are widely used in presswork industry. There exist one-side magnets in gift boxes, phone boxes, tobacco and wine boxes, MP3 boxes and moon cake boxes, etc.
2、They are also widely used in leather industry, such as bags, suitcases, briefcases, traveling bags, cell-phone cases, wallets and so on.
3、In Stationery industries, one side magnets are used in notebooks, white boards, folders, and magnetic name badges.

The Purchasing Considerations of One-side Magnets.
The manufacture of one-side magnets is to artificially put the neodymium magnets into the metal plates. So it will take a pretty long time to produce. Customers who want to purchase should place the order in advance.

There are many specifications of one-side magnets. China Rare Earth Magnet limited can customize the magnets according to your requirements. Please send e-mail to us if you have any demand for magnets.

Tags: permanent magnet

What kind of permanent magnet needs a mould in production?

Someone might wonder what magnet needs a mould while others do not. China Rare Earth Magnet Limited would like to discuss about this.

Permanent magnets that our company mainly manufacture: NdFeB magnet, ferrite magnet, SmCo magnet, bonded NdFeB magnet and injection molding magnet.

Sintered NdFeB magnet, also called strong magnet, has the strongest magnetism which is also one of its advantage. NdFeB magnet can be customized as per customer’s requirement without molding.

Apart from sintered NdFeB magnet, bonded NdFeB magnet is also a kind of neodymium. Its advantage is that it can be shaped in one shot without further processing. Bonded NdFeB magnet can be made into various complex shapes while sintered NdFeB magnet can not. The application of bonded NdFeB magnet can significantly decrease the volume and weight of motor. A mould of bonded NdFeB magnet ranges in price from $450 to $900.

Ferrite permanent magnet, also called normal magnet. Its magnetism is weaker than NdFeB magnet’s and thereof its price is lower than NdFeB’s. So ferrite magnet is wildly used. Ferrite magnet is divided into two classes: molding ferrite magnet and cutting ferrite magnet. Obviously the former needs a mould during production while the later do not.


SmCo magnet is mainly used in product which works at a temperature higher than 300℃. SmCo magnet is seldom applied as its high price. Mould is not a necessary for the production of SmCo magnet.

Mould is a must for the production of injection molding permanent magnet. We have available moulds in various size and we welcome your inquiry with detailed information.


To sum up, magnets need moulds during production include injection molding magnet, bonded NdFeB magnet, irregular ferrite magnet, multi-pole magnetized ferrite magnet and large-sized NdFeB magnet.

Do you know magnets that need mould during production better after reading above content? Feel free to contact us if there is any question.

Tags: permanent magnet

What are the advantages of electromagnets? What are their main applications?

Electromagnets are not our products of permanent magnets. There are many differences between them. We have encountered with customers that need electromagnets many times.  Unfortunately, China Rare Earth Magnet Limited does not produce this kind of electromagnet. Today we are talking about the advantages and applications of electromagnets.

What are the advantages of electromagnets? 
Electromagnets have many advantages: such as its magnetism can be controlled by electricity and power outage; its magnetic strength can be controlled by the strength of the current; its north and south poles can be controlled by the direction of the transformation current.

What are the main uses of electromagnets?
Electromagnetic switch, traction electromagnet, electromagnetic crane, grinder suction cup, solenoid valve, electromagnetic brake, water level automatic alarm, automatic electrical electromagnetic system and so on.

To give you a few examples, such as the electromagnetic crane has a large electromagnet. Through the current, a few tons of heavy steel material can be sucked up to move to a designated location. There is no fixture on the Grinder Workbench in the machinery factory, but the machined work piece is sucked on top for processing. Workbench is also a large electromagnet. It can attract steel or work pieces with power. When there is no power, it can release steel or work pieces. Electromagnetic dressing machine by the role of electromagnets can separate iron and non-ferrous matter.

If there is any other question about permanent magnet, please feel free to contact us.

Tags: permanent magnet, electromagnets

How to measure the surface gauss of cylindrical permennt magnet?

Cylindrical magnet, one of the commonest permanent magnets, is normally of NdFeB or ferrite material. But somebody knows little about the magnetization and how to test the surface gauss of magnet some how. So below is information about that in more detail.

What are magnetization orientations of cylindrical permanent magnet?

There are two traditional magnetization directions, diametrically magnetized and axially magnetized. Usually, disc magnet is magnetized through axle while cylindrical magnet is diametrically magnetized. And of course the actual orientation is subject to customer’s requirement.

How do we test cylindrical magnet’s surface gauss value?

There are two favorable places for testing, both ends and flank of cylindrical magnet. And please kindly note that the testing point must be smooth. Where to measure is actually depend on the permanent magnetic material and cutting direction chosen during the production.

For most cylindrical magnets, the best testing point are the ends. Sliding the gauss meter on the magnet, you could collect data and find the max gauss value. As for diametrically magnetized magnet, please move the gauss meter along the flank of the magnet. Thus the gauss range of magnet is obtained.

Do you have a general understanding of How to measure the surface gauss of cylindrical permanent magnets now?

Tags: permanent magnet, cylindrical magnet

Do you Know How the Permanent Magnets are Used for Beneficiation?

Everybody knows that lots of mineral resources are symbiotic, that is, there are varieties of minerals mixed together inside the mined material. These substances have different magnetic properties. According to this feature, people developed professional mineral processing equipment—magnetic separators that are equipped with permanent magnets.

By taking the advantages of the differences in magnetism and magnetic strength of minerals that have different components. These components will be attracted by permanent magnets, and because of the different attraction force, we can separate the minerals with different magnetic property that are mixed together, and achieve the beneficiation by magnetism.

Beneficiation magnets are mainly ferrite magnets and neodymium magnets. One machine uses a lot of them.

What kinds of magnetic separators will use permanent magnets?

There are mainly magnetic pulleys, conveyor magnetic pulleys, strong magnetic pulleys, supper strong magnetic rollers, magnetic bars, conveyor belt permanent magnets, the salvage magnetic plates, remote iron suction plates, etc.

So that’s how the permanent magnets are used for beneficiation. If you have any demand for magnets (neodymium, ferrite) that are used for magnetic separators, please contact us—China Rare Earth Magnet Limited.

Tags: permanent magnet, magnetic separators

What are the differences between the different sizes of magnets produced by a batch of permanent magnet materials?

When we produce strong magnets, we often encounter some customer questions, that is, customers found the magnetic force of different sizes of magnets is different, even though they are produced by a batch of material. In this case, we magnet manufacturers will explain to customers, magnets, its magnetic force is mainly depended on Gauss value. This Gauss value is the one our permanent magnet manufacturers often say the magnetic unit. Usually the larger value of this Gauss value, the stronger the magnetic force, then why the different dimensions produced, its Gaussian value is not the same? Let me talk about this question today.

The composition of the powerful magnet is made of NdFeB permanent magnetic material, in the theoretical data, if we use the same material under the same condition, while the magnet thickness decreases, the Gauss value of the magnet will also decrease, and then the magnetic force becomes weaker. The magnetism will increase with the increase of the area.

Here is one key point I would like to mention. The higher the surface Gauss value of magnets indicates the greater the magnetic force per unit area! Magnetic force = unit area of surface Gauss value* per unit area. However, it can’t jump to the conclusion that the magnetic force must be large with high surface Gauss value.

Therefore, permanent magnets in the same batch of materials produced by different sizes of magnets will have a Gauss value difference, which is actually a normal phenomenon. If you still have the other relevant questions of magnets, please feel free to contact us.

Tags: permanent magnet, magnet manufacturer

Permanent Magnets Might be Used in Microsoft’s Product 20190702

The Microsoft Surface computer is one of the most remarkable products of the Windows camp and is a best seller. Microsoft has rarely found a flaw regarding the hardware side in the business. However when it comes to their Surface lineup, it seems that something is different. Because a number of people swear by the Microsoft Surface Notebooks and their experience. But a new patent recently leaked from Microsoft’s stables which indicate some differences on their future plans!

However, the iFixit disintegration experts and the countless users who have to repair the Microsoft Surface have had something to complain about. The Surface is also renowned for it’s difficult to disassemble and repair design. With the latest Microsoft Surface Pro 6, iFixit experts gave then 1 point of repairability (out of 10 points). And for Surface Laptop 2 was got 0 of repairability, which means that it is almost impossible to repair this laptop. As for the Microsoft Surface Book 2, it received a 1 point score by iFixit as only the SSD can be exchanged.

The difficulty of repair resulted from nothing but a sum of two points. One is that Microsoft’s structural design is too complicated, and the other is that Microsoft uses too much glue.

Fortunately, Microsoft may have realized this problem and might attempt to fix it. A recently leaked patent from Microsoft shows that a new assembly technology was introduced. Guess what!!
From a patent perspective, Microsoft has tried to replace glue with permanent magnet to connect and secure electronic components to the housing through one or more magnetic attachment points.

The positive influence of this patent is that it can speed up the manufacturing process. Besides, foreign publications also have an opinion that this improvement can make the repair and recycling of computer much easier.

This technology seems like a creative solution. Secure the design points of a computer by using permanent magnets might make the overall disintegration easier to process. What’s more, people don’t need complex tools or familiar with the repair of their machines.

Tags: permanent magnet

The Operation on China Rare Earth Permanent Magnet Material Industry in 2018

The Operation on China Rare Earth Permanent Magnet Material Industry in 2018

According to the statistics of China Magnetic Materials Branch of Rare Earth Industry Association, in 2018, many industries such as new energy vehicles, energy-efficient appliances, electric tools, industrial robots have been a crucial support for the development of rare earth permanent magnet material industry. The development quality of the industry is constantly improving; the output of products is steadily increasing; the key enterprises have kept a great posture. The grain boundary mobility and other advanced technology have promoted further, and expand the new application fields such as the transaction motor for high speed railway. Output of sintered neodymium magnets blank is about one hundred and fifty-five thousand tons, has increased 5% than last year. The output of bonded neodymium magnets is 7 thousand tons, has increased 5%. The output of SmCo magnet is two thousand and five hundred tons, is same as last year.

Tags: permanent magnet, China magnet

Permanent Lifting Magnets 20190109

China Rare Earth Magnet Limited is specialized in producing permanent lifting magnets which are applied in all different types of related industry, such as steel supply, machine and etc. If you work on a business that often needs to move one big object from one place to another, using lifting magnets will be a good choice. Our lifting magnets can successfully transport objects that are very heavy.

Features and Benefits:
Integrated with the neodymium material with the strongest magnetic force
High lifting capacity
Easy for operation
Low weight-easy to move
No power consuming

We are top neodymium magnets manufacturer in China, welcome to send your inquiry about permanent magnets by email; we will reply you within one working day.

Tags: permanent magnets, lifting magnets

Ring Countersink Hole Neodymium Permanent Magnets 20190107

China Rare Earth Magnet Limited manufactures ring countersink hole neodymium magnets.
These neodymium magnets with countersink hole are ideal for any carpentry, home improvements or DIY purposes.

Specification:
Material: Neodymium Permanent Magnet
Grade: N35
Size: D20xd*xd4x3x5mm

Coating: NiCuNi
These three layers of coating, Nickel+Copper+Nickel, are very well in protecting magnets from corrosion and provide a smooth and glossy surface, thereby greatly increasing the longevity of magnets.
Magnetization direction: Across the thickness

We are top neodymium magnets manufacturer in China, welcome to send your inquiry about permanent magnets by email; we will reply you within one working day.

Tags: custom neodymium magnets, permanent magnet