2.2.1 RADIOGRAPIC TESTING :-
The radiation used in Radiographic Testing is a higher energy (Shortest wavelength) version of the Electromagnetic waves that we see as visible light. The radiation can come from an X-ray generator or radioactive source.
Isotope – Natural source of radiation
X-ray – Artificial source of radiation
Main uses of RT:
1. RT is used to inspect almost any material for surface and subsurface defect.
2. X-ray can also use to locate and measure internal features.
3. Confirm the hidden part in assembly.
Equipment’s used in RT:
1. X-ray generator
2. Radioisotope source
3. Radiographic film
4. Exposure vaults and cabinets
1. Put the component in front of radiation exposure.
2. Selection of penetrometer.
3. Put the radiographic film on opposite side of component.
4. Activate the radiographic source.
5. Evaluate the radiographic film observations and find out the defects.
1. It can be used to inspect virtually all materials.
2. Detects surface and subsurface defects.
3. Ability to inspect complex shapes and multilayered structures without disassembly.
4. Minimum part preparation is required.
1. Extensive operator training and skill required
2. Access to both sides of structure is usually required
3. Orientation of the radiation beam to non volumetric defects is critical
4. Field inspection of thick section can be time consuming
5. Relatively expensive equipment