Countercurrent type driving magnetic drum separator

The leading countercurrent type magnetic drum separator is not just a piece of equipment. This is the intersection of three requirements faced by concentrator engineers, recycling line operators and cement plant technologists: high levels of cleaning while maintaining productivity, stability in dusty, wet and abrasive environments, and minimal maintenance costs. We have been designing and implementing such separators since 1993. During this time, we have seen how the standard "counter flow" design solves problems where other types of magnetic drums lose up to 40% of efficiency.

Why exactly the countercurrent principle is not a fashion, but the physics of separation

The separator operates according to a simple but strict rule: material is fed from above along the axis of the drum, and a magnetic field is created inside a rotating cylinder. In a counterflow design, the flow of material moves towards the rotation of the drum. This slows down the relative speed of particles near the surface - and gives the magnetic field time to “capture” weakly magnetic inclusions: iron oxides, fragments of worn parts, rust, even small shavings from 30KhGSA steel. In a forward flow, particles slide faster, and the proportion of those going into the tail increases. In practice, the difference in the degree of purification reaches 22–28% for materials with an iron content below 0.8%. We tested this at three factories in the Krasnoyarsk Territory: with the same input parameters (humidity 6–8%, fraction 0–10 mm), the countercurrent separator retained 99.3% of ferromagnetic impurities, while a similar direct-acting drum retained only 77.1%.

What Makes Him a “Leader”—Beyond Marketing

The term “leading” here does not mean the sales leader, but the presence of three key technical solutions that other manufacturers either omit or partially implement:

Modular magnetization system: 16 individual segments with adjustable field intensity (from 150 to 650 mT). You can turn off the input zone by increasing the field in the reset zone - without stopping the line.
Housing made of wear-resistant steel 110G13L: surface hardness - 52–56 HRC. When working with granite crushed stone, the service life of the drum increases by 2.3 times compared to standard steel 09G2S.
Self-adjusting belt tension system: The load cell adjusts the tension every 47 seconds. Eliminates slippage during sudden changes in feed volume - a common cause of emergency stops in quarries.

These solutions do not add value “for the sake of numbers.” They reduce maintenance downtime by 68%, reduce spare parts consumption by 41% and allow operation without reconfiguration at humidity fluctuations of ±5% and ambient temperature from −25 °C to +45 °C.

Where he will fail - and why it is important to know

Some customers expect the Countercurrent Master Magnetic Drum Separator to remove everything down to paramagnetic particles. This is a misconception. It is not intended for cleaning quartz sand from hematite or kaolin from titanomagnetite. Its task is to reliably protect crushers, mills and conveyor belts from ferromagnetic wear. If your raw materials are dominated by weakly magnetic minerals, you need a combination: first a counterflow drum, then a high-intensity separator with an electromagnetic system. We always carry out trial separation of samples for free: send 5 kg of material - you will receive a report with a recommendation on the scheme and calculation of the expected degree of purification.

How to choose a specific model - three steps, not ten tables

The choice begins not with the catalog, but with three parameters:

Maximum mass flow (t/h), and not volumetric - because the density of the material affects the thickness of the layer on the drum. For 120 t/h at a density of 1.6 g/cm³, a drum with a diameter of 900 mm is needed, not 750 mm.
Largest fraction size. If there are pieces >120 mm, a reinforced frame and an increased gap between the drum and the receiving tray are required - otherwise jamming will occur.
Operating conditions: open area or indoors? Is there a risk of pressurized water entering? Is explosion protection required (Ex d IIB T4)? The design of the housing and the type of bearings depend on this.

On the LONGI Corporation website there is an interactive selection calculator: enter these three values and you will receive a list of suitable models indicating dimensions, weight, power consumption and required voltage. No registration, no calls, no obligations.

The counter-current master magnetic drum separator is a solution that works where other separators require constant adjustment. It does not replace the engineer. It frees him from shift-by-shift intervention to focus on optimizing the entire line. Tested on 4000 installations. Confirmed by operating data. Available for your production - today.