Two Magnetic Circuit Arrangements of Magnetic Bars

Magnetic bars are magnetic devices composed of stainless-steel housings, neodymium-iron-boron magnetic materials, and magnetic conductive materials. They are also known by various names such as "magnetic rods," "magnet bars," "high-intensity magnetic bars," or "demagnetizing bars." Their primary function is magnetic separation and iron removal. Depending on the application scenario, magnetic bars feature two magnetic circuit arrangements: longitudinal arrangement and transverse arrangement.

Longitudinal arrangement is typically used for magnetic separation in slurries and powdered materials.

Transverse arrangement is specifically suitable for removing magnetic impurities from strip-shaped materials like electrode sheets and foils, especially in industries such as new energy lithium batteries, where it is widely applied in battery electrode sheets and separators.

How to distinguish between longitudinal and transverse magnetic circuit arrangements? We will illustrate this with relevant practical visual materials.

From visual materials, it can be seen that the magnetic poles of longitudinally arranged magnetic bars are distributed in a segmented pattern, creating alternating peaks and valleys in magnetic strength between adjacent poles. This design allows the slurry to cut across the magnetic lines of force perpendicularly during fluid processing, achieving efficient magnetic separation and iron removal. According to magnetic bar selection tables, longitudinally arranged magnetic bars can be cylindrical, square, or rectangular in shape. Drawing on years of production and application experience, Dongpu Magnetoelectric has developed magnetic bar configurations with varying magnetic pole spacings. By minimizing pole spacing while maintaining magnetic field intensity, the company optimizes the efficiency of magnetic separation.

For strip-shaped materials such as lithium battery electrode sheets and separator foils, longitudinally arranged magnetic bars prove ineffective. The non-magnetic gaps between consecutive poles often lead to incomplete separation, leaving residual magnetic impurities. To address this challenge, Dongguan Dongpu Magnetic Technology Co., Ltd. has developed a specialized transverse magnetic bar arrangement for battery electrode sheets and separator foils.

For detailed structural diagrams and magnetic bar specifications, refer to the accompanying visual materials:

Due to the unique properties of strip-shaped materials such as battery electrode sheets and separator foils, the direction of magnetic field lines must be perpendicular to the material’s movement to ensure comprehensive magnetic field coverage with no dead zones, thereby achieving efficient magnetic separation. This technology has been extensively adopted across the lithium battery industry, from original equipment manufacturers to end-user power battery factories, and transverse magnetic bar arrangements have gained widespread recognition for their effectiveness.