← Glossary

Root Pass

The root pass is the bottom weld bead that fully penetrates a gap and joins the parts from the inside. Its correct execution is crucial for a defect-free joint.

Physical-Chemical Mechanism of Action

The root pass makes the first contact between the metal parts to be joined and initiates the welding process. It must penetrate the entire gap to create a continuous connection.

Metallurgical Relevance & Risks in Welding

A faulty root pass can lead to incomplete penetration of the gap and cause notches or stress concentrations. This increases the risk of cracking and reduces the toughness of the joint.

Workshop Practice & Instructions

Ensure that the root pass forms a continuous weld and penetrates the entire gap. Use high-quality shielding gas for precise work and regularly monitor the joint quality.

MetallurgieSchweißtechnik

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