Weld Acceptance Level
Weld quality group defines acceptable imperfection limits based on service conditions. It grades quality requirements into levels.
Physical-chemical mechanism of action
The weld quality group (SNB) is a system that sets allowable tolerances for imperfections in weld quality. These groups consider both the mechanical loading condition and the chemical composition of the material.
Metallurgical relevance & risks in welding
The SNB is crucial for the safety and service life of welded joints. A too high imperfection rate can lead to cracks, failure, or reduced mechanical properties. Choosing the correct SNB group is therefore essential for a safe and stable joint.
Shop practice & instructions
To correctly apply the weld quality group, the following steps must be taken:
1. Load calculation: Determine the mechanical load on the weld.
2. Material selection: Choose a suitable material with appropriate toughness and strength.
3. Welding process: Use a suitable welding process that meets the SNB requirements.
4. Quality control: Check the weld against the specified imperfection limits of the SNB group.