Liquid Penetrant Testing

Based on the properties of capillary action, or the phenomenon of a liquid rising or climbing when confined to a small opening due to surface wetting properties of the liquid, Penetrant testing is used for finding surface breaking discontinuities on relatively smooth, nonporous surfaces. Liquid or Dye Penetrant inspection (LPI/DPI), also called Penetrant Testing (PT), is a widely applied and low-cost inspection method used to locate defects which are open to surface under inspection. Its ability to easily detect defects in all non-porous materials (metals, plastics, or ceramics) make it popular in the industry.