The quality requirements for the fabrication on fusion-welded joints consisting of steel are compiled in the international standard ISO 5817: "Welding – Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding excluded); Quality levels for imperfections".
In the terms of a specialist generic standard, this international standard is the basis for normative stipulations in order to assess welded joints in the various areas of application of welding technology such as in pressure vessel, steel, pipeline and rail vehicle construction etc. Furthermore, it must be taken as the basis for the assessment of the test pieces of steel welders as well as of test pieces from welding procedure tests according to ISO 15614-1: "Specification and qualification of welding procedures for metallic materials – Welding procedure test – Part 1: Arc and gas welding of steels and arc welding of nickel and nickel alloys".
The app is useful for the circle of people who are not yet practiced in implementing the limiting values stipulated in the standard for the individual case. For example, the reference cards are used in order to teach them how to correctly interpret the various imperfections and their specific appearances on the radiograph and how to categorize them on a quality level of the standard according to their sizes. The app also serves the manufacturers, the operators and the testing agencies as an aid and a decision-taking means for the evaluation of welds in fabrication. It relates to individual welds and not to a product or a whole component. Thus, it is possible to make distinctions with regard to the quality levels for the respective welds on one component.