← Glossary

Fill pass

Fill passes refer to the weld passes between the root and cap passes, used to fill the remaining joint cross-section.

Physical-Chemical Mechanism of Action

This fill forms a continuous weld between the lower (root) and upper (cap) layers. During the welding process, the metal flows into the opening and fills the remaining cross-section.

Metallurgical Relevance & Welding Risks

Insufficient fill can lead to porosity and reduced mechanical properties. Too much fill, on the other hand, can cause overfill and distortion of the part, which impairs strength.

Workshop Practice & Instructions

Make sure the welding process lasts long enough to completely fill the joint cross-section. Monitor the weld regularly and correct the position or welding if necessary.

MetallurgieSchweißtechnik

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