Penetrant Testing

Theoretic background

Compared to the magnetic particle inspection, the penetrant testing differs in the way that defects as cracks or pores etc. can be proven also on non-magnetizable materials. The principle of penetrant testing is based on the fact that a penetrant does not only want to spread optimally on a surface, but also penetrates every defect of a surface, due to its specific characteristics. After removal of the exceeding penetrant from the surface, the penetrant in the material discontinuity can be made visible by applying a developer.

The penetrant testing systems are available for daylight-visible indications (colour contrast penetrant testing) or with fluorescent penetrant, visible under UV-light.

 Numerous typical applications

With penetrant testing, surface discontinuities on all iron metals and non-iron metals can be detected fast and without bigger expenditures of parts and machines. Even on many plastic materials, ceramic materials, glass etc. penetrant testing can be done, assumed that the material is not effected by the penetrant itself. Prerequisite for this testing procedure is that the defect is open to the surface. Penetrant testing is mainly used for the testing of welding seams, cast iron, in shipbuilding, automobile construction, apparatus- and container manufacturing.