Penetrant testing

What is penetrant testing?
Penetrant Testing acc. to EN ISO 3452-1:2013

With the Penetrant Testing procedure (also known as DP test or dye penetrant inspection) you can quickly determine surface discontinuities on all iron metals and non-iron metals, some plastics and ceramic materials, glass, etc., provided that the discontinuities are open to the surfaces.

The liquid penetrant test method is used in the examination of welding seams, cast pieces, in shipbuilding, automobile and aircraft construction, apparatus and tank construction, etc.

Liquid penetrant inspection can be carried out with at daylight visible (red dye penetrant) and/or under UV-light fluorescent penetrants. The PT method is charactestic for the fact that, contrary to the magnetic particle inspection (MT), defects or discontinuities can be proven also on not magnetizable materials.

Process description:

The testing procedure consists of four separate processing steps, for which the following products are necessary:

  1. Precleaning (MR® Remover)
  2. Application of penetrant (MR® Penetrant)
  3. Excess penetrant removal (MR® Remover or water)
  4. Application of developer (MR® Developer, white)


Data sheets

Process description
Process overview

Product information (PDF)

MR 3001
MR 3002

Application of penetrant
MR 67 PS
MR 68 C
MR 68 H
MR 68 NF

Excess penetrant removal
MR 79
MR 85
MR 88
MR 91 H

Application of developer
MR 70
MR 70 H

Penetration Test Red:White
Penetration Test Red:White 2