Radiography 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. Radio graphic 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 dependent 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 radio-graphic systems are portable and thus can be used in the field and elevated positions.
LIQUID PENETRANT TESTING APPLICATIONS
There are two different radioactive sources available for industrial use; X-ray and Gamma-ray. These radiation sources use higher energy level, i.e. shorter wavelength, versions of the electromagnetic waves. Because of the radioactivity involved in radiography testing, it is of paramount importance to ensure that the Local Rules is strictly adhered during operation.
Computed Tomography (CT) is one of the lab based advanced NDT methods that TWI offers to industry. CT is a radiographic based technique that provides both cross-sectional and 3D volume images of the object under inspection. These images allow the internal structure of the test object to be inspected without the inherent superimposition associated with 2D radiography. This feature allows detailed analysis of the internal structure of a wide range of components.
- ASTM E 94, Standard Guide for Radiographic Examination
- ASTM E 155, Standard Reference Radiographs for Inspection of Aluminum and Magnesium Castings
- ASTM E 592, Standard Guide to Obtainable ASTM Equivalent Penetrameter Sensitivity for Radiography of Steel Plates 1/4 to 2 in. [6 to 51 mm] Thick with X Rays and 1 to 6 in. [25 to 152 mm] Thick with Cobalt-60
- ASTM E 747, Standard Practice for Design, Manufacture and Material Grouping Classification of Wire Image Quality Indicators (IQI) Used for Radiology
- ASTM E 801, Standard Practice for Controlling Quality of Radiological Examination of Electronic Devices
- ASTM E 1030, Standard Test Method for Radiographic Examination of Metallic Castings
- ASTM E 1032, Standard Test Method for Radiographic Examination of Weldments
- ASTM 1161, Standard Practice for Radiologic Examination of Semiconductors and Electronic Components
- ASTM E 1648, Standard Reference Radiographs for Examination of Aluminum Fusion Welds
- ASTM E 1735, Standard Test Method for Determining Relative Image Quality of Industrial Radiographic Film Exposed to X-Radiation from 4 to 25 MeV
- ASTM E 1815, Standard Test Method for Classification of Film Systems for Industrial Radiography
- ASTM E 1817, Standard Practice for Controlling Quality of Radiological Examination by Using Representative Quality Indicators (RQIs)
- ASTM E 2104, Standard Practice for Radiographic Examination of Advanced Aero and Turbine Materials and Components