Radiographic Testing for pWPS ISO 17636-1,-2 & ISO 10675
Radiographic Testing is a non-destructive testing of welding components and assemblies that is based on differential absorption of electromagnetic radiation of very short wave-lengths or particulate radiation by the part or test piece being tested. Because of differences in density and variations in thickness of the part, or differences in absorption coeficient caused by variation in composition, different portions of a test piece absorb different amounts of penetrating radiation. Amount of radiation passing through the part and expose the film emulsion, tafter exposed the film by radiation called Latent image, this can not view before developing the film. After developing latent image can be visible. We can use florescent screen or monitored by various types of electronic radiation detectors, it is called real image.
The term radiography testing usually implies a radiographic process that produces a permanent image on film. Although in a broad sense it refers to all forms of radiographic testing. Neutron radiography refers to radiographic testing using a stream of neutrons rather than electromagnetic radiation.
Compared to other NDT methods, radiography is expensive. High activity sources require heavy shielding for protection of personnel. RT is limitaions in thickness of material vs nature of source. Volumetric indications find better than Planer type discontionuity. And orientation of discontinuity play major roll. Parallel or anguler to the plate surface planer discontinuity given wrong informatioms.
Due hazards of living tisue for radiation energy, now a days in the world, maximum country RT job is convert to UT. Because both are find tottal volmetric test of welds.