FOERSTER
Application notes
Ferromagnetic Contamination in Non-Ferrous Metal Scrap

Reliable Detection of Ferromagnetic Contamination in Non-Ferrous Metal Scrap

Ferromagnetic foreign objects in copper, aluminum and other non-ferrous metal scrap can affect material quality. MAGNETOMAT detects and localizes hidden contamination, enabling automated evaluation and sorting.

The challenge

When recycling copper, aluminum and other non-ferrous metals, ferromagnetic contamination must be reliably detected. Particularly in compacted scrap, steel parts or wires can be hidden inside the material and remain invisible from the outside.

For automated quality control, such foreign objects must be reliably detected and localized even at high material throughput. At the same time, magnetic interference in industrial environments can affect the measurement and must be taken into account when designing the inspection system.

The solution

For inspection, the non-ferrous metal scrap is transported on a conveyor belt through a magnetized inspection zone. A magnetizing yoke installed ahead of the inspection zone generates the required magnetic field. Ferromagnetic foreign objects are magnetized and can subsequently be detected using field and gradient probes.

Depending on the inspection task, multiple probe pairs can be arranged around the material to reliably detect and localize contamination. An appropriate probe configuration and magnetic shielding help minimize the influence of interfering magnetic fields from the production environment.

The MAGNETOMAT 1.790 acquires and processes the measurement signals. Defined thresholds allow different levels of contamination to be evaluated and corresponding control signals to be provided for downstream marking or sorting processes.

The result

Magnetic inspection enables automated quality control of non-ferrous metal scrap directly within the recycling process. Ferromagnetic foreign objects can be reliably detected and localized even when hidden inside compacted scrap bales.

Contaminated material can be evaluated according to defined criteria and selectively marked or sorted out. At the same time, the acquired measurement data is available for quality assurance and further analysis. In this way, MAGNETOMAT supports consistent material quality and efficient sorting processes.