Tag Archives for Radiographic

Radiographic Examination – Applications and Limitations

It is sometimes thought that RT is the best NDE method that can be used for detecting flaws, because it is mandated by the ASME Code for certifying the quality of newly constructed pressure vessels. This is not true. RT … Continue reading

29. April 2018 by Jack
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Radiographic Examination – Radiograph Quality

The acceptability of a radiograph for the detection of flaws is determined with a device, referred to as a “penetrameter,” that is placed upon the surface of the workpiece when the exposure is made. Penetrameters are relatively thin pieces of … Continue reading

29. April 2018 by Jack
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Radiographic Examination – Exposure

The exposure of the photographic film by radiation passing through the workpiece is determined by the intensity of the radiation multiplied by the time of the exposure. The optical density of the developed negative increases with increasing exposure. ASME Code, … Continue reading

29. April 2018 by Jack
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Radiographic Examination – Photographic Film

The radiation which passes through the workpiece is recorded by photographic film. The radiographs are usually interpreted visually with the aid of a high intensity light source (light box), but optical densitometers or image analyzers are occasionally used. Two primary … Continue reading

29. April 2018 by Jack
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Radiographic Examination – Radiation Sources

Both x-rays and gamma rays can be used as the incident radiation. Energy and intensity are the most important characteristics of the incident radiation. The energy of the incident radiation determines its ability to penetrate the workpiece. Higher energy radiation … Continue reading

29. April 2018 by Jack
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Radiographic Examination – Physical Principles

X-rays and gamma rays penetrate steel, but the intensity of the incident radiation will be attenuated as it passes through the material. The degree of attenuation depends on the thickness and density of the material. Flaws can have the effect … Continue reading

29. April 2018 by Jack
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Radiographic Examination (RT)

RT is very useful for detecting both surface and internal flaws, and it is the primary NDE procedure required by the ASME Code to verify the quality of welds during construction. However, the associated radiation hazard makes it difficult to … Continue reading

29. April 2018 by Jack
Categories: In-Service Inspection | Tags: | Leave a comment