Farbpenetrantentest

Farbpenetrantentest, also known as Dye Penetrant Inspection (DPI) or Liquid Penetrant Testing (LPT), is a non-destructive testing (NDT) method used to detect surface-breaking defects in a wide range of materials. It is particularly effective for finding cracks, porosity, laps, seams, and other discontinuities that are open to the surface. The process relies on the ability of a low-viscosity liquid dye to penetrate into these surface flaws.

The test typically involves several steps. First, the surface of the item to be inspected is thoroughly cleaned to remove any dirt, grease, or other contaminants that could prevent the penetrant from entering defects. Next, a liquid penetrant, which is either fluorescent or visible, is applied to the surface. This penetrant is allowed to dwell for a specific period, known as the penetration time, enabling it to seep into any surface flaws.

After the dwell time, the excess penetrant is carefully removed from the surface. This is a critical step, as residual penetrant can lead to false indications. A developer is then applied. The developer draws the trapped penetrant out of the subsurface flaws, making them visible against the developer background. For fluorescent penetrants, this is observed under ultraviolet (UV) light, while visible penetrants can be seen under normal light conditions. Any indications observed are then evaluated to determine if they represent actual defects. Farbpenetrantentest is a cost-effective and widely used technique in industries such as aerospace, automotive, and manufacturing.