metal detection or x-ray inspection
Metal Detection or X-Ray Inspection?
July 24, 2021
Metal Contaminant Types
Metal Contaminant Types
October 1, 2021
X-ray Basics

Understanding X-ray Inspection

X-RAY BASICS

X-rays are simply a high energy light source. Its wave length is higher than visual light but follows the same basic principles.  The diagram below shows some of the x-ray basics with the range of light wavelengths visible and invisible.

 

 

 

 

 

 

There are two types of X-ray Systems: Automatic and Manual. Automatic systems utilize linear array technology and Manual systems use image intensifying technology. The base resolution of an automatic system is determined by the diode size and the speed of the product. A Manual Systems resolution is infinite and only limited by video techniques. In both cases, the physics associated with X-Rays are the same, but a manual system with human viewers may achieve a better detection result.

 

 

 

 

 

 

 

SENSITIVITY

Sensitivity is determined by the systems-based resolution and product density. The denser the product, the more difficult it becomes to detect a foreign material. When dealing with dense foreign, objects, the atomic number associated with such contaminants must be greater than that of the product. For example: a cherry pit is hard but less dense than the meat of the cherry, therefore it is not detectable by X-Rays.

Here is a list of come common contaminants meant to be found when utilizing X-Ray systems:

CONTAMINANT – DENSITY g/cc
  • Polyethylene……………0.857 g/cm3
  • Polyvinyl………………….0.892 g/cm3
  • UHMW…………………….0.931 g/cm3
  • Rubber…………………….1.2 g/cm3
  • PETG………………………..1.38 g/cm³
  • Acetal (Delrin)………….1.4 g/cm3
  • PTFE………………………..2.2 g/cm3
  • Borosilicate……………..2.23 g/cm3
  • Soda-Lime Glass………2.5 g/cm3
  • Aluminum……………….2.7 g/cm3
  • Ceramic (AL203)……..3.7 g/cm3
  • Ceramic (ZRO2)……….5.6 g/cm3
  • Stainless Steel 316…..7.82 g/cm3
  • Ferrous……………………7.85 g/cm3
  • Non-Ferrous…………..8.48 g/cm3

A rule of thumb is that if a contaminant floats in water then it will not be detected by X-Rays.

 

 

 

 

 

 

 

 

 

If you have any other questions regarding X-Ray or would like to further explore the ins and outs of the technology, Regal is here to help.  Feel free to call us at (630) 942-8461.  You can also email regalpack@regalpack.com

Or, for X-Ray inspection laminate OR thermoform test pieces call 866-691-8560, email testrods@testrods.com.  Keep in mind that while acetal (plastic) can be used for x-ray, we generally do not recommend it.  Depending on your application and x-ray settings, acetal can leave a “shadow” and cause a false positive.

Leave a Reply

Your email address will not be published. Required fields are marked *