Traditional radiographic testing (RT) Technique used for searching internal defects in materials

The technique is the same used in the medical field. A beam of radioactive waves is flashed through the object to be examined, and it’s absorbed in a different manner depending on the thickness and density of the material traversed.

Behind the object is placed a photographic plate that, after development, will take different shades of gray in proportion to the dose of radiation received. In this way we highlight possible defects such as cavities, cracks, different density of the material.

Checkable products:

The checkable products can be: welds, rolleds, forgeds, drawns, castings, machined.


The advantages are the high degree of reliability and the ability to also highlight internal defects. Moreover, radiographic testing can be documentable in time.


The limits are the impossibility of use on materials that are opaque to radiation or with a particularly complex geometry, and the thickness of the object to be examined. Even the most powerful X-ray does not exceed thicknesses greater than 80 mm of steel (180 mm for gamma rays). In addition there are inevitable problems related to radioprotection security.

Available equipment:

  • GILARDONI 350 Kv/6
  • GILARDONI 300 Kv/6 P
  • GILARDONI 300 Kv/5
  • GILARDONI 200 Kv/5
  • GILARDONI 200 Kv MHF 200 POC

For materials with an higher thickness, such as forgeds and welded sheets for the nuclear industry, we use a linear accelerator of 2 Mev power. Centrotest Srl has got 2 bunkers for carrying out radiographic checks and for the storage of radiographic X-ray equipment, and 2 laboratories (including a mobile one) for films development.

Main reference standards:

  • EN462, EN 1435, EN 12517, EN 17636
  • ASME V Art. 2
  • ASTM E 1742, ASTM E 747