Radiographic Testing using X-ray / Iridium / Selenium : Radiography of weld joint, Profile shots for corrosion monitoring, ASME Code pressure vessels, Piping as per API 1104, ASME B31.3/31.1, Pipelines, Structural etc.,
- Radiography is one of the two main volumetric testing methods, along with ultrasonic. Some materials, either because of their thickness or grain structure, may be difficult to penetrate with ultrasonic, or a permanent visual record may be required and, therefore, radiography may be an alternative.
- Radiographic testing works by producing short-wave X- or gamma radiation and directing it at an object. Radiation penetrates matter to a certain extent and, if this penetration is enough for it to pass through the object, this radiation can be captured on a photographic film.
- If an object has a high density, ie a thicker object, it absorbs more radiation causing less radiation to hit the film, which produces a lighter image. If an object has a low density, ie when the through section is reduced or there is a lower-density material such as slag (compared to the surrounding material), it will absorb less radiation causing more radiation to hit the film, producing a darker image.
In industrial radiography, two sources of radiation are used: X-rays and gamma rays. Essentially they are the same, ie electromagnetic radiation, the difference being the way they are produced.