UT Flaw (Ultrasonic Flaw Detection) in boilers is used to detect internal defects such as cracks, porosity, or wall thinning in tubes and other components. Ultrasonic waves are emitted into the material, and their reflections are analyzed to identify imperfections that are invisible from the outside. This method can provide in-depth information about the material's internal condition without damaging it. With UT Flaw, potential failures can be identified early so that maintenance actions can be planned appropriately.