A: Ultrasonic Testing
Ultrasonic testing (UT) is a form of nondestructive testing used to detect and measure material defects, measure thickness, inspect for corrosion and to monitor welding processes. UT utilizes short bursts of sound energy at high frequency, usually above 1 MHz, to create sound waves which are transmitted through the material. This method of nondestructive testing is most commonly used on thicker materials, and because of the high frequency sound which is used, it can highlight material thickness, internal defects and corrosion which would otherwise go unnoticed.
B: Radiographic Testing
Radiographic testing (RT) is a non destructive test used mainly to find any internal defects, flaws and voids within a test piece. It works by passing, X-ray or gamma radiation through the test piece which is transformed onto a film to be examined. The type of radiation used and the intensity of the radiation varies to ensure suitable results. Radiographic testing is used mainly in industries such as aerospace, oil, gas and petrochemical to discover any imperfections invisible or hidden to the naked eye.
C: Magnetic Particle Testing
Magnetic Particle Testing (MT) is a common form of non destructive testing. It is mainly used for surface level inspection, for example cracks and porosity in ferromagnetic materials such as cast iron, steel and stainless steel. It works by charging the test piece to a strong magnetic field and then using any defects, flaws and imperfections to be identified. The process of magnetic particle testing is relatively quick, simple and cost effective, which is why it is so commonly used.
D: Visual Testing
Visual testing (VT) is another nondestructive testing methodology used to evaluate the surface condition of a test piece. This method is a low cost, simple technique, however does have its limits. For example visual testing cannot detect defects on the interior of a part, corrosion under a coating or cracks which have been covered. Typically this method is used to identify surface defects such as cracks, weld anomalies and surface discolouration.
