magnetic separator iron separator

It is often thought that a magnetic separator and an iron separator are the same thing. In fact, if you dig deeper, there is a difference, and it is fundamental in specific conditions. For example, on a conveyor line for bulk materials there is one thing, but for the purification of liquid media or in a crushing complex there are different requirements for the design and magnetic system. Many customers, especially at the start, do not take this into account, and then face a shortage of product purity or frequent stops for cleaning. I went through this myself.

From theory to the workshop: where real problems begin

Here, for example, is a classic drum magnetic separator. In theory, everything is clear: the material moves along the tape, the magnetic field pulls out ferromagnetic impurities. But in practice, the key is not just the strength of the field, but its configuration and stability. If the field gradient is not designed for a specific fraction of the material, small particles simply will not “feel” it. it is enough to separate from the main flow. I have seen cases where a seemingly powerful magnet was installed, but the efficiency was low precisely because of this.

Or another point - automatic cleaning. Many self-cleaning systems are good on paper, but in conditions of high dust or humidity, the same scraper mechanism can become clogged, magnetized chips begin to stick, and instead of automation, we end up with manual work every shift. This is not a question about the quality of the hardware, but about the engineering development of components for a real environment. This is where the experience of the manufacturer, who has encountered different scenarios, is important.

By the way, about the manufacturers. When you are looking for reliable equipment, you often come across the name LONGI Corporation. They are not the first year on the market, and what is important is that their profile is mining equipment. The website https://www.ljmagnet.ru makes it clear the scale: the enterprise has been established since 1993, its own large site, more than a thousand employees. For me, this is always an indirect but important sign: a company that produces itself, and does not just resell, usually understands these very nuances of application more deeply. Their range of magnetic separators appears to be born from real-life applications, not just catalogues.

Hanging iron separator: when to ?just hang? not enough

Let's move on to iron separators. Hanging - it would seem the simplest thing. But its installation is a whole science. The height above the belt, the angle of inclination, the speed of the conveyor - everything affects it. I once observed a situation at a processing plant: the separator was hanging too high, and large pieces of metal were simply “pushing through” without having time to be attracted. And the fine fraction, on the contrary, was captured. As a result, the most dangerous pieces for the crusher slipped through.

Another subtle point is nutrition. There are no questions for permanent magnets, but electromagnetic iron separators require a stable voltage. In conditions of remote quarries or old workshops with drawdowns in the network, the efficiency of the electromagnet can “float”. You have to either install stabilizers, which makes the system more expensive, or initially look towards modern permanent magnets based on rare-earth alloys. In the same LONGI, for example, in the descriptions they emphasize different types of magnetic systems, which hints at the possibility of choosing according to the conditions.

We must not forget about the design of the case. In abrasive environments, regular steel wears out quickly. You need either wear-resistant inserts or special coatings. This is a detail that is often missed in specifications, and in operation it results in a reduction in service life. A good manufacturer will usually offer options because they know where the equipment will work.

Case study: crushing complex and “invisible” problem

I would like to give an example that clearly shows the importance of making the right choice. There was a project at a crushing and screening complex for processing construction waste. After the initial crushing there was a powerful magnetic separator, everything was fine. But on the secondary crushing line, after the crash, the bearings on the impact crusher constantly failed. It seems that all the metal should have been removed.

It took a long time to figure it out. It turned out that the problem was in the so-called “non-magnetic” metal - mainly in pieces of hardened steel (such as balls from bearings) and in aluminum.Magnetic separatorNaturally, I didn’t take them. But when struck in the crusher, these pieces broke off microparticles that were already ferromagnetic, and it was they that killed the bearings. The solution was not to replace the separator, but to install an additional, more sensitiveiron separatorat a stage after the rumble, which would catch this secondary metal fines. Sometimes the problem is solved not by strengthening the main node, but by adding another, more accurate one.

This is about an integrated approach. You can’t just buy one inlet separator and call it done. The technological chain must be analyzed as a whole, at each processing stage. Manufacturers who are engaged not just in sales, but in engineering, like LONGI, with their experience in mining equipment, are usually able to offer such an equipment arrangement. Their factory area of ​​140,000 m2 and the production of 4,000 units of equipment per year indicate the possibility of making them not individually, but in series, but for different tasks.

Evolution of materials: from ferrites to rare earth magnets

The element base has changed greatly over the past 15-20 years. Previously, mainly ferrite magnets or electromagnets were used. Reliable, but bulky and not always strong enough for fine cleaning. With the advent and cheaper cost of neodymium-iron-boron (NdFeB) alloys, a lot has changed. Modernmagnetic separatoron rare-earth magnets, with the same dimensions, it can produce a field many times stronger.

But there are pitfalls here too. These magnets are temperature sensitive. When constantly working in a hot shop (say, next to dryers), they can irreversibly lose their strength. Therefore, in the passport you should always look at the maximum operating temperature of the magnet class. Good manufacturers take this into account at the design stage, offering either cooling or choosing a magnet with a higher temperature class, which, of course, is more expensive.

Interestingly, advances in materials have made it possible to create magnetic gratings and rods of very small diameter but with high strength. This is critical for the food or chemical industry, where it is necessary to capture the smallest metal inclusions from liquids or highly dispersed powders. Such tasks are already far from rough mining, but the principle is the same - to create a maximum field gradient in the area where the product passes.

Final thoughts: Not the hardware, but the solution

In the end, what I want to say. Choice betweenmagnetic separatorandiron separator, and choosing a specific model is not about the catalog and prices. This is about the analysis of raw materials, technological map, conditions in the workshop, and even about the qualifications of service personnel. Sometimes it is better to put two simpler devices at different stages than one super powerful one, but not there.

Experience, including negative ones, suggests that it is worth working with suppliers who are themselves manufacturers and have decades of experience behind them, like Shenyang Scientific Electromagnetic Company LONGJI LLC. When more than 60% of the workforce is college-educated and a business produces thousands of units per year, that usually means having in-house engineering departments that can tailor a solution rather than simply shipping a box from a warehouse.

Therefore, my advice is to always ask not just technical specifications, but cases for conditions similar to yours. And look at the details: how cleaning is implemented, what the case is made of, what class of magnets is used and how it is protected. These seemingly little things ultimately determine whether the equipment will work for years without problems or will become a headache for the technologist. It all comes down to understanding the process, and not to the magnets themselves.