Radiographic Testing (RT) is a nondestructive examination (NDE) technique that involves the use of either x-rays or gamma rays to view a non-uniform material. Radiographic testing is often used to view machinery, such as pressure vessels and valves to detect for flaws. The type of radiation used, gamma or x-ray, is largely dependant on the size of the part being tested.

Compared to other techniques, radiography has several advantages. It is highly reproducible and the data gathered can be stored for later analysis. Moreover, radiography is an effective tool for testing a number of different materials, not much surface preparation is required, and radiographic systems are portable and thus can be used in the field and elevated positions.

There are numerous types of radiographic testing including conventional radiography, computer aided radiography, digital radiography, and real time radiography. Each works slightly differently and has its own set of advantages and disadvantages:

  • Conventional Radiography uses a sensitive film which reacts to the emitted radiation to capture an image of the part being tested. This image can then be examined for evidence of damage or flaws.
  • Digital Radiography doesn’t use film, unlike conventional radiography. It uses a digital capture device to create digital images. It allows for a much shorter exposure time, so that the images can be looked at more quickly.
  • Computer Aided Radiography uses computer based image processing tools to enhance and manipulate RTR images in order to improve resolution and focus on areas of interest in a digital radiograph.
  • Real Time Radiography, like its name suggests, occurs in real time. This process uses a phosphor screen or flat panel to create a real time image of the part being inspected which can be examined as it is being tested. While this method tends to be more convenient than the others, the images tend to be of lower quality.
 

Related Topics

Acoustic Emission Testing (AET) Advanced Ultrasonic Backscatter Technique (AUBT) Eddy Current Array (ECA) Electro Magnetic Acoustic Transducers (EMAT) Guided Wave Ultrasonics Infrared Thermography (IT) Infrared Thermometry Liquid Penetrant Examination (LPE) Magnetic Flux Leakage (MFL) Magnetic Particle Testing (MPT) Meandering Winding Magnetometer Array (MWMA) Pulse Reflectometry Pulsed Eddy Current (PEC) Thermography Ultrasonics

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Articles
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  • September/October 2013 Inspectioneering Journal
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  • January/February 2008 Inspectioneering Journal
    By Sanjoy Das at Bhabha Atomic Research Centre, P.R. Vaidya at BARC, and B.K. Shah at BARC

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  • July/August 2007 Inspectioneering Journal
    By Sanjoy Das at Bhabha Atomic Research Centre, P.R. Vaidya at BARC, and B.K. Shah at BARC

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  • July/August 2005 Inspectioneering Journal
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  • September/October 1995 Inspectioneering Journal
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