Root Face Width
Root face width of the weld joint is the remaining vertical thickness at the root side of the edge preparation. It affects the stiffness and penetration of the steel, controls the heat balance, and prevents cracks.
Physicochemical Mechanism of Action
The land width of the weld joint affects the local heat balance in the first weld pass. A larger land width increases thermal conductivity and speeds up burn-through of the steel. A smaller land width slows burn-through, which improves control over the welding process.
Metallurgical Relevance & Welding Risks
Too large a land width can lead to uneven heat distribution and too-fast burn-through, which causes cracks and distortion in the steel. Too small a land width slows burn-through and raises the risk of hot cracks and lack of fusion at the edges.
Workshop Practice & Instructions
The optimal land width depends on the welding process and the steel type. For good results: with TIG welding a land width of 1.5 to 2 mm is recommended; with MAG welding 1 to 1.5 mm. Watch for even burn-through and keep an eye on the temperature in the weld zone.