Weld seam inspection DIN EN 1090

The Weld seam testing using macroscopic and microscopic analysis is an indispensable material science method in the field of quality assurance, especially for safety-relevant components and structures (pressure vessel construction, road and railway bridge construction, rail vehicle construction, pipeline construction). This weld seam test can be used to detect defects in Weld structure, lack of fusion, penetration, insufficient penetration, cracks and microstructure defects This method is a destructive examination in the Metallography – the one metallographic sample preparation using a wet cutting machine and Grinding (separating, embedding, grinding, polishing, etching). Macroscopic evaluation / macro recording is carried out by manually measuring the geometric dimensions such as lines and angles. Typically the A-dimension measurement in which the length of the bond between the base material and the melt is determined.

In 2012, a standard revision (DIN EN 1090) was carried out which significantly increased the requirements for welding and welding specialists. In particular, a welder's test and a welding procedure test (weld seam test) are a basic requirement for being allowed to carry out welding on safety-relevant parts.

All subsequent weld seam inspections can be carried out using simple PC inspection software with image capture and geometric measurement functions. The microscope for weld seam inspection is a macro microscope with 20x magnification. 

The  A-measure of a weld seam can be determined easily in a matter of seconds. Various software tools are available for A-dimension measurement. Calibrated microscopes/macroscopes are required for the measurement. An essential element for good image quality is the lighting.

Macroscopic images of various weld seams

Depending on the type of component, different joints and weld seam types arise. In addition, the thicknesses of the materials to be joined vary and the types of metal can also be different.