Frequently Asked Questions

Below are frequently asked questions about metal detection and rejection systems.

What Is A Metal Detector & How Does It Work?

A metal detector is an electronic device for detecting the presence of metal. It is made up of a transmitter and receiver antenna. The electronics look at signal changes and decide if the changes are caused by metal.

Where Should I Put the Metal Detector?

If you are trying to protect your industrial processing or manufacturing equipment, then it should be placed as close to the infeed section as possible while still allowing ample space to stop before metal can enter. If you want to protect your final product, then the metal detector should be located as close to the end of the production line as possible — after the product has been packed.

What Is Product Effect?

It is the product’s effect on the signals picked up by the metal detector. Moisture, fat, acidity, temperature, salinity, orientation and mass are all factors.

What Types of Metals Do Metal Detectors Look For?

Metal detection and rejection systems look for ferrous, non-ferrous, and stainless steel. Ferrous metals are magnetic metals like steel and iron. These are the easiest to detect. Non-ferrous metals are copper, aluminum, brass and bronze. And finally, stainless steel metals such as: 302, 304 and 316 are the hardest to detect. Generally, a piece of non-magnetic stainless steel must be 1.5 times larger, than a ferrous metal, in order to be detected by a metal detector.

How Do HACCP Rules Relate to Detection?

The main purpose of the HACCP initiative is to develop a procedure that identifies possible locations in your production line where product contamination can occur and to create a method of inspecting those locations on a regular basis to prevent contamination. Documentation of these inspections is a major feature of any HACCP plan. Modern metal detectors have a record keeping ability to provide a history of contamination incidents.

Why Do I Need A Metal Detector?

There are two reasons. The first is protection of your expensive processing equipment. The second is to protect the integrity of your product. One small piece of metal can be devastating to your company’s reputation and equipment if found in a product.

How Do I Choose A Metal Detector?

Make sure that the metal detector is appropriate for your unique application, the aperture size is appropriate for the various products that will be tested and that the detector is in the right location. Our experts can help you choose which metal detector is appropriate for your needs.

What Is Sensitivity?

The minimum diameter sphere that can be consistently detected at the center of the metal detector opening. There are two kinds of sensitivity: “maximum” or “in-product”. Maximum is the best sensitivity possible under ideal conditions. In-product is the sensitivity obtained when actually inspecting the product.

What Factors Influence Sensitivity?

Product effect, size, shape, type, orientation of metal contaminants, the size of the opening of the metal detector, as well as the environment of operation that the metal detector occupies can all affect the metal detection system’s sensitivity.

What Should I Do If Metal Is Found?

It should be collected and examined in order to trace the metal back to its source. If an automatic reject device (removes contaminated product automatically) is not feasible, then the product needs to be removed from the line and manually inspected.

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