High-Low Misalignment
Weld misalignment is a geometric defect in butt joints where the parts are not in the same plane, creating additional bending stresses.
Physical-Chemical Mechanism of Action
A weld mismatch occurs due to uneven expansion or shifting of the sheets during welding. This can lead to areas of stress that build up in the material and cause bending stresses.
Metallurgical Relevance & Welding Risks
Weld mismatch can cause several problems: It increases the risk of cracks or fractures, because the stresses in the material are not evenly distributed. It can also impair the strength of the weld and reduce the service life of the components.
Workshop Practice & Instructions
To avoid weld mismatch, it's important that the sheets are butted straight before welding. This can be achieved by careful alignment and using settling tools. The sheets should also be pressed evenly to minimize stresses. For complex parts, it's advisable to create a control image before welding to identify and correct any shifting or deviations early.