How do metal detection systems work?

How do metal detection systems work

When detecting metal contaminants in food, most metal detection systems operate using a balanced coil system, with three coils wound onto a non-metallic frame. 

As food applications pass through the aperture, the transmitter coil generates a magnetic field to make metal contaminants identifiable. The second and third receiver coils can then detect the presence of these metal contaminants.

When a metal contaminant is detected, our systems have a range of rejection devices to efficiently remove the contaminant. This includes a reject arm or photogated air blast, for example.

As well as these, the systems have alerts in place to notify you of any contaminants found, so you are always aware of when and where they are identified.

What types of food does a metal detection system inspect?

Metal detection systems can detect metal contamination in various types of food applications. This includes packaged, unpackaged, raw, processed, dry, wet, and frozen foods.

Some examples include:

... as well as ready-meals, sauces and pastes, snacks and sweets, and pet food.


What is spherical sensitivity in metal detection?

Spherical sensitivity is a measurement of how a metal detector can detect different types and sizes of metal contaminants. The higher the sensitivity of your system, the smaller and more irregular shapes of metal that can be detected.

There are various factors that can affect the sensitivity of a metal detection system. This includes the type and size of the metal contaminant, the object orientation, the aperture size, and product characteristics.

Metal Detection Sensitivity Explained

Learn about the importance of spherical sensitivity in metal detection including what sensitivity is and how it is measured.

What type of metal detection system do I need?

Smart Metal Detection Solutions

Metal detection systems are available for a range of food, non-food and pharmaceutical applications. Our portfolio includes tunnel and throat metal detectors, and gravity fall, pipeline, pharmaceutical and conveyorized metal detection systems.

There are a range of things you need to consider when considering between the different types of metal detection in food processing to choose for detecting metal contamination in food production. These considerations can include the type of food you’re inspecting, such as wet, dry, packaged, or unpackaged.

You can also consider the nature of your production line and the specific critical control point you place the system. For example, are your products moving along in a conveyor belt, being pumped along, or free-falling?

You can also explore a range of different inspection technologies, from tuned frequency technology to Dual-Simultaneous and Multi-Simultaneous frequency, to help you achieve the right system for product inspection of your food manufacturing processes.

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