NDT Methods
RADIOGRAPHY TESTING (RT)
This method is based on the same principle as medical radiography in a hospital. A piece of radiographic film is placed on the remote side of the material under inspection and radiation is then transmitted through from one side of the material to the remote side where the radiographic film is placed.
The radiographic film detects the radiation and measures the various quantities of radiation received over the entire surface of the film. This film is then processed under dark room conditions and the various degrees of radiation received by the film are imaged by the display of different degrees of black and white, this is termed the film density and is viewed on a special light emitting device. Discontinuities in the material affect the amount of radiation being received by the film through that particular plane of the material.
Qualified inspectors can interpret the resultant images and record the location and type of defect present in the material. Radiography can be used on most materials and product forms, e.g. welds, castings, composites etc.
Radiographic testing provides a permanent record in the form of a radiograph and provides a highly sensitive image of the internal structure of the material. Radiography is split into two main categories
- Radiographic Testing
- Radiographic Interpretation
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