Radiographic Examination is a form of non-destructive testing (NDT) that involves the use of penetrating X (generated x-ray) or Gamma (Iridium 192) radiation to examine parts and products (welds) for flaws that could be detrimental to their intended use.
At Africana NDT we specialize in using the latest technologies and techniques for radiographic testing projects. Our highly experienced radiographers are extremely capable in employing many specialty techniques involving geometrically-challenging parts and pieces, often-times where other companies cannot offer working solutions. Africana NDT provides radiographic services in both our shooting bays and in the field right at the customer’s location.
Gamma rays are produced by a radioisotope.
A radioisotope has unstable nuclei that does not have enough binding energy to hold the nucleus together. The spontaneous breakdown of an atomic nucleus resulting in the release of energy and matter is known as radioactive decay. Most of the radioactive material used in industrial radiography is artificially produced.
This is done by subjecting stable material to a source of neutrons in a special nuclear reactor.
This process is called activation.
X-rays are allowed to pass through the test material. A cassette containing film is placed behind the test material (part to be inspected). A penetrameters (or Image Quality Indicator IQI) is placed on the side of the source adjacent to the weld.
After the prescribed time of exposure, the source is turned off and the film is send for development in the dark room (A dark room is a place where the film is developed). After development the film is inspected with the help of a viewer.