← Glossary

Excessive penetration

Sagging is the protruding of filler metal at the root underside when the heat input is too high or the gap bridging is inadequate. This impairs flow dynamics in pipelines.

Physicochemical mechanism of action

Sagging occurs when molten filler metal (such as silicon or titanium) protrudes at the bottom side of the gap. This happens due to excessive heat input during welding or insufficient bridging of the gap.

Metallurgical relevance & risks when welding

Sagging can lead to increased resistance and reduced flow in pipelines. It can also reduce the service life of the weld and lead to cracks or distortion if not properly addressed.

Workshop practice & instructions

To avoid sagging, ensure adequate gap bridging and control the heat input. If sagging occurs, it can be corrected by additional weld passes or mechanical grinding of the root side.

MetallurgieSchweißtechnik

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