Non-destructive testing (NDT), as the name suggests, is a method of testing materials, components, structures, or assemblies without causing damage or affecting their workability. In contrast to other ways of testing, where the subject cannot be used after the procedure, this technique allows the subject to be utilized after the procedure. It has the obvious benefit of not wasting resources during testing, making it a more efficient and cost-effective method. But what precisely are NDT methods? How can you test something without damaging it?
Thanks to technological advancements, there is now a varied range of methods for performing NDTs, each with its own set of parameters and degrees of effectiveness. Each method is specific and works best with distinct types of materials.
Some of the most prominent Non-Destructive testing techniques are listed below.
Radiography Testing(RT): Radiography Testing spots imperfections in a component or system through X-radiation or gamma-radiation. This kind of test uses an X-ray generator or a radioactive isotope to send radiation into a material you’re testing and onto a detector, like a film. After directing the radiation, inspectors can look at key readings from a shadowgraph created by a detector, helping them see potential issues, such as density alterations.
Visual Testing(VT): Visual Testing involves the collection of visual information on a material’s status. This form of testing is the most basic, as you can complete it by simply looking at an asset. For more in-depth visual inspections, you can use a Remote Visual Inspection device to get a more precise look at materials.
Leak Testing(LT): When you have a leaking structure or vessel, you can use Leak Testing to study the leaks and identify an asset’s defects. Inspectors often conduct leak testing with soap-bubble examinations, pressure gauges and listening devices.
Acoustic Emission Testing(AE): Acoustic Emission Testing refers to the process of utilizing acoustic emissions to discover an asset’s potential imperfections and defects. Much of this test involves looking for acoustic energy bursts, as these bursts indicate defects. Inspectors also examine a burst’s arrival time, location and intensity to spot potential issues.
Ultrasonic Testing(UT): With Ultrasonic Testing, an inspector transmits high-frequency waves into an asset or material to spot material property changes. A primary type of ultrasonic testing utilizes pulse echos. In this test, an inspector sends sounds into an asset and then measures the sound’s echos, as these echos can help them spot surface imperfections.
Magnetic Particle Testing: Magnetic Particle Testing involves the process of spotting a material’s flaws by reviewing disruption in the material’s magnetic field’s flow. To conduct these tests, an inspector induces a magnetic field in an asset very susceptible to magnetization. Once they induce the magnetic field, they place iron particles over the material’s surface. These particles showcase any disruptions and provide visual indicators of imperfections’ locations.
Liquid Penetrant Testing: When an inspector conducts Liquid Penetrant Testing, they’ll start by placing a coating of liquid featuring a fluorescent or visible dye over an asset. Inspectors then take off any extra solution from the asset’s surface. The remaining solution will stay in breaks in the surface, revealing any defects. After they spot any defects, they’ll remove the fluorescent dye, using ultraviolet light to examine defects. With regular dyes, inspectors will study defects via the contrast between the developer and penetrant.
Eddy Current Testing: As a form of Electromagnetic Testing, Eddy Current Testing involves inspectors measuring a material’s magnetic field for the strength of eddy currents, sometimes referred to as electrical currents. After measuring these currents, the inspector can often spot defects in the asset or material. Particularly, inspectors look for electric current interruptions that indicate the material has imperfections.
Post time: Apr-22-2022