How to Equip Magnetic Separator for Raymond Mill？

Function of Magnetic Separators in Raymond Mill Systems

During industrial grinding, once iron impurities mix into raw materials, they will not only damage grinding rollers and rings and increase the operation and maintenance cost of Raymond Mills, but also block mills, classifiers, conveying pipelines, cyclone collectors and other equipment, reducing classification accuracy and production efficiency. If iron impurities enter finished products such as ceramic glazes, coatings and papermaking raw materials, powder quality including color, purity and uniformity will be directly affected. Meanwhile, collisions of iron parts inside the equipment may trigger sparks and abnormal vibration, bringing potential safety hazards. Therefore, equipping high-efficiency magnetic separators is critical to guarantee safe and stable production and product quality of Raymond Mills.

In actual grinding production lines, iron removal is rarely completed by a single unit. Multi-stage iron removal processes are adopted to handle impurities in different forms at various stages:

Common Types of Magnetic Separators for Raymond Mills

Common magnetic separators used with Raymond Mill systems include suspended self-discharging magnetic separators, pipeline magnetic separators and permanent magnetic pulleys (magnetic head pulleys).

Suspended Self-discharging Magnetic Separator (Left), Pipeline Magnetic Separator (Middle), Permanent Magnetic Pulley (Right)

Selection Recommendations for Magnetic Separators Matched with Raymond Mills

Conveying Method

For coarse-grained materials with fast flow rate via belt conveying, suspended self-discharging magnetic separators or permanent magnetic pulleys are recommended, featuring robust structure and impact resistance. Suspended magnetic separators perform continuous iron removal during transportation, while permanent magnetic pulleys are generally installed at the head of belt conveyors to separate ferromagnetic substances. For powder materials delivered by pneumatic conveying or vertical gravity fall, pipeline magnetic separators are the choice. Their magnetic rods fully cover the cross-section of flow channels to capture iron impurities efficiently.

Material Moisture and Viscosity

For materials with high moisture or viscosity, suspended magnetic separators with stronger magnetic force are preferred to effectively prevent material adhesion and blockage. Permanent magnetic pulleys are also applicable provided materials can be thrown off smoothly without adhesion reducing separation efficiency.

Characteristics of Iron Impurities

For large or sporadic iron pieces, select suspended self-discharging magnetic separators. They have large processing capacity and wide magnetic coverage for efficient iron removal. For fine or powdery iron scraps, pipeline magnetic separators are ideal. Closely arranged magnetic rods deliver excellent adsorption for micro iron scraps, especially for high-precision iron removal. For materials with low content and fine iron impurities, permanent magnetic pulleys can complete separation during material transfer with simple structure and efficient operation.

Process Budget

Process budget and other factors should be considered during magnetic separator selection. Suspended self-discharging magnetic separators suit continuous operation with sufficient space. Automatic iron discharge greatly cuts labor cost. Pipeline magnetic separators feature compact structure and fit confined spaces such as pipeline joints. Automatic types adapt to continuous production processes while non-automatic versions cost less and satisfy basic intermittent production needs. Permanent magnetic pulleys integrate iron removal and transmission, delivering high overall cost performance for new or upgraded conveying lines.

Pitfall Avoidance Guide for Magnetic Separators Supporting Raymond Mills

Install Only One Magnetic Separator Before Feeding into Mill

Metal contaminants mainly come from raw ore, and also from worn crusher components. A single magnetic separator before milling cannot protect upstream equipment. Besides, iron scraps ground into fine powder become harder to eliminate and lower powder whiteness.

The correct practice is to install magnetic separators after crushing and before milling respectively for multi-stage iron removal protection.

Improper Installation Position of Magnetic Separator

Magnetic separators have strict limits on material layer thickness (usually ≤100mm). Over-thick material layers prevent the absorption of iron impurities at the bottom and result in low iron removal efficiency.

The correct installation is on horizontal sections with thin and uniform material flow, such as conveyor head or vibrating screen outlet.

Neglect the Impact of Material Properties on Iron Removal Performance

High-moisture materials passing directly through magnetic separators will wrap iron impurities and hinder adsorption. Wet materials may also stick to magnetic poles and weaken magnetic strength, lowering iron removal efficiency.

The proper approach is to dry high-moisture materials before iron removal, or equip vibrating screens to separate wet and dry materials.

Ignore Cleaning and Maintenance of Magnetic Separators

Permanent magnets gradually demagnetize after years of service, and electromagnetic coils age with reduced attraction. Without inspection and replacement, iron removal capacity will be lost. Meanwhile, accumulated iron impurities without regular cleaning cause magnetic short circuits. Dust buildup on coils leads to poor heat dissipation and weaker magnetic force, which may damage equipment or contaminate finished products in severe cases.

The correct practice is regular cleaning, standardized operation, demagnetization prevention, safety inspection and proper maintenance of magnetic separators.

Neodymium Iron Boron Permanent Magnet (Picture)