Lead Dry Drum Magnetic Separator

A dry drum magnetic separator is more than just equipment. This is a filter that solves three problems at the same time: protects crushing stations from breakdowns, increases the purity of the final product, and reduces downtime for maintenance. But not every device copes with this reliably. We saw how, at one quarry in the Kemerovo region, three different separators in a row failed when processing granite crushed stone with a high content of ferrous inclusions. Cause? Insufficient magnetic field depth and weak drum design. That's why we recommendleading dry drum magnetic separator- a proven system that operates without failure even at a load of 320 t/h and ambient temperatures up to +45°C.

Why “dry” is not a compromise, but a technology requirement

Wet separation seems familiar: water removes dust, cools, and helps separate particles. But in real conditions it creates new problems. Water sludge requires a closed cycle, pumps, settling tanks and regular filter cleaning. At one mining and processing plant in the Sverdlovsk region, the volume of sludge reached 18 m³/hour - and all of this had to be disposed of. The dry method eliminates these costs completely. It works in air, without water, without chemicals, without secondary waste. The main condition is the right choiceleading dry drum magnetic separator: it must provide a holding force of at least 12 kG on the surface of the drum and have an inclination angle of 12–15° for reliable discharge of magnetized impurities.

Three critical parameters that determine the result

Customers often ask: “Why does one separator give 98% purification, and another only 87% with the same input data?” The answer lies in three points:

• Magnetic field gradient. Not the induction itself, but its change along the radius. With high-quality equipment, the gradient exceeds 1500 Gas/cm - this allows you to capture particles as small as 0.1 mm, including dusty ferromagnetic debris;
• Drum coating thickness and type. A 16 mm thick anti-slip rubber coating is a prerequisite for working with abrasive materials. Thinner - wears off quickly. Thicker - reduces grip efficiency;
• Rotation speed and gap adjustment. The optimal rotation speed is from 22 to 36 rpm. The gap between the drum and the belt must be set with an accuracy of ±0.5 mm. We conducted the test ourselves: with an increase in the gap by 1.2 mm, the proportion of residual impurities increased by 42%.

These parameters cannot be “adjusted” on the spot. They are set at the design stage. That is why it is important to choose equipment designed taking into account Russian operating conditions - temperature changes, high humidity and significant dust.

How to avoid common mistakes during implementation

Some people think: “Let’s install a separator and the problem is solved.” But practice shows otherwise. The three most common errors are:

1. Installation without preliminary analysis of the fractional composition. If more than 30% of the material is a fraction below 5 mm, additional vibration feed or tilt angle correction is required;
2. Ignoring nutritional requirements. Magnetic systems with permanent neodymium magnets do not require power supply, but electromagnetic modifications require a stable voltage of ±2%. Changes cause fluctuations in field strength and the passage of impurities;
3. Lack of backup channel for service. On a production line, stopping for 40 minutes means 22 tons of backlog. Therefore, we always provide a bypass branch or parallel installation.

The solution is not in power, but in thoughtfulness. Each project begins with sample material sampling and laboratory magnetic susceptibility analysis. This is the only way to accurately select the type, dimensions and operating mode.

Practice tested by time and thousands of tons

Shenyang Longji Scientific Electromagnetic Co., Ltd. has been producing industrial magnetic separators since 1993. Over 30 years, the company has produced more than 120,000 units of equipment. The Fushun plant occupies 140,000 m² and employs 1,200 people, of which more than 720 are engineers and designers with higher education. Every year the company produces over 4,000 separators, includingleading dry drum magnetic separator, adapted to Russian standards: GOST R ISO 9001, requirements of TR TS 010/020, climatic version UHL1.

Technical catalogs, connection diagrams, installation recommendations and videos with real commissioning tests are available on the website https://www.ljmagnet.ru. But the main thing is not the documents, but the result. At one reinforced concrete plant in the Belgorod region, after replacing an outdated separator with a model from LONGI, the number of crusher failures decreased by 76%, and the service life of conveyor belts increased by 2.3 times. This is not a figure from a presentation. This is the SCADA system data for 18 months of operation.