Dye penetrant inspection

Just like magnetic particle inspection, dye penetrant inspection (also called PT – testing) is a surface crack testing method. With this proven and relatively easy test procedure, surfaces, open cavities and fine cracks can be detected. The inspection involves a number of successive steps and can be performed quickly.



The component under inspection, for example a welding seam, should be ground in order to prevent any confusion about the component’s features. This is followed by a thorough cleaning that can be done either with special cleaners or with water. After this, the surface under inspection is treated with a penetrant – we usually use a red coloured foam to prevent misting.
The component is then cleaned again after a brief waiting period. It is important to ensure that the component is not over-washed.
Subsequently, the component is sprayed with a developer! Any possible cracks or pores present will now be shown and be clearly visible.

This test is suited as a secondary test procedure, for example for gas pipes or fittings, and as a main inspection procedure, i.e. for various components in power stations.

The testing medium is consistently checked prior to any use.


In our laboratory, we can either apply the procedures as described under “Mobile” or, in the case of large quantities (production components in the automobile industry, for example), we can apply the immersion method.
For this procedure, the components are first dipped in a fluorescent penetrant before being cleaned with water (under UV-light) and dried.
Features such as cracks, etc. are easily discernible in UV-light.

Our dipping tank has a size of 1130 x 725 x 690 mm (inner dimensions).
Here we also apply continuous checks of the testing medium!
Our testing mediums are all biologically degradable.