This blog is all about providing a general information about NDT to people familiar with the process. So what is NDT and what are the techniques applied in it?
NDT stands for Non Destructive Testing, which is a process of evaluating, testing and inspecting different materials and their components. In other words, the part of the machine again becomes useful after conducting this specialised testing.
The test is conducted to determine a material’s physical components like ductility, impact resistance, fracture toughness, fatigue strength, and tensile strength.
Different NDT methods and their benefits
There are various types of NDT methods. Some of the common ones are Magnetic Particle Testing, Electromagnetic Testing, Guided Wave Testing and many more. Each of the techniques are conducted on different applications with various advantages. The tests are a form of solution to upgrade industrial environment and provide commercial independence.
The most common method of NDT
1.Welding Corrosion Testing – is one of the most common methods of non destructive testing. Welding inspection is further categorised into two forms, Radiographic Testing and Ultrasonic Testing. Obviously, these tests are conducted to determine the internal integrity of a weld without destroying the welded component. Let’s take a deeper look into these specialised tests.
2. Radiographic Testing – In this method X-rays are used from a tube which is X shaped. In some cases, gamma rays are also used from a radioactive isotope. The main objective of radiographic testing is similar to medical radiography. In this case, rather than passing the penetrative radiation through human body, it is passed through a solid object on a photographic film. The photographic film is the final image of an object’s internal structure. If the image appears whitish, it means the body of the object is thin or porous. On the contrary, if an image appears dark, it means that the walls of the object are at their best quality. In actual, an object’s thickness and density depend upon the amount of energy (radiation) absorbed.
3. Ultrasonic Testing – In this method, mechanical vibrations are used which are similar to sound waves in a high frequency. A beam of ultrasonic energy is passed through an object without damaging it. If the energy reflects it means it is a cause of discontinuity.
Thus, radiographic and ultrasonic testing are simplified.
The advantages of NDT are enormous when the quality and productivity are considered. After conducting all these tests, manufactured items are considered safe and legal.