Why Metal Detectors And X-Ray Inspection Systems Should Be Used Together

By Erik Brainard , President

Detecting contaminated products
With high concern about food safety among consumers, food manufactures have implemented various quality control measures. Although the number of contaminant accidents has been decreased, there still are significant numbers of food contamination cases reported every year, with some developing into critical issues. There are various contamination: metal, stone, rubber, glass, plastic, etc. Therefore, it is important to understand the characteristics of contaminants and select correct inspection systems.

What is the difference between metal detectors and X-ray inspection systems?
Although metal detectors and X-ray inspection systems are major tools used for contaminant inspection having different detection methods, they are common for monitoring product effects. Products containing contaminants show not only product effect but also the contaminant effect. Therefore, you can identify passed products and faulty products. Let’s call these effects “effect values”. Now we compare the effects values of metallic and non-metallic contaminants using the metal detector and the X-ray system.

Metal detectors can catch the changes in magnetic fields caused by products passing through the detection head. Metallic contaminants can be detected because they generate large effects in the magnetic fields. Whereas non-metallic contaminants, such as rubber and glass, are not detectable since they don’t affect the magnetic fields.