Radiographic Testing (RT)

Radiographic Testing (RT), or industrial radiography, is a nondestructive testing (NDT) method of inspecting materials for hidden flaws by using the ability of short wavelength electromagnetic radiation (high energy photons) to penetrate various materials. Either an X-ray machine or a radioactive source (Ir-192, Co-60, or in rarer cases Cs-137) can be used as a source of photons.

We are equipped with several different types of cameras including crank and crawler cameras.Conventional Radiography is a nondestructive examination method that uses X-ray and Gamma ray for detecting internal imperfections, for measuring wall thickness and for detection of corrosion. With RT, the material is exposed to a homogenous ray from a radioactive isotope or an X-ray tube while a negative film is positioned behind the material to be examined. The test part will stop some of the radiation while thicker and denser areas will stop more of the radiation. After development of the film, thickness and density differences (material imperfections) will show as blackness differences. Acceptance criteria define whether or not the indication is non-acceptable (a defect) or not.

There are many advantages to radiography including: inspection of a wide variety of material types with varying density, ability to inspect assembled components, minimum surface preparation required, sensitivity to changes in thickness corrosion, voids, cracks and material density changes, the ability to detect both surface and subsurface defects and the ability to provide a permanent record of the inspection. The disadvantages of radiography are: safety precautions are required for the safe use of radiation, access to both sides of the specimen are required, orientation of the sample is critical, and determining flaw depth is impossible without additional angled exposures.