Excessive drag from a dirty liner is likely to cause which problem?

Excessive drag from a dirty liner is likely to cause which problem?

• A. Porosity And Cracking In The Weld.
• B. Slippage Or Bird Nesting At The Drive Rolls.
• C. Excessive Undercut Or Lack Of Fusion.
• D. Damage To The Liner And Contact Tip.

Answer: (B)

Excessive drag from a dirty liner interferes with smooth wire feeding. The liner guides the welding wire from the spool to the contact tip, and its inner surface must be clean and smooth to minimize resistance. When dirt or damage increases drag, the drive rolls can’t push the wire consistently, causing slippage where the wire doesn’t advance at the commanded rate. The friction can also pull the wire into a tight bend or kink near the drive rolls, creating a tangled buildup often called a “bird nest.” These feed irregularities disrupt arc stability and welding performance. While other weld defects can arise from different issues, the direct consequence of dirty liner drag is slippage and bird nesting at the drive rolls.

Excessive drag from a dirty liner interferes with smooth wire feeding. The liner guides the welding wire from the spool to the contact tip, and its inner surface must be clean and smooth to minimize resistance. When dirt or damage increases drag, the drive rolls can’t push the wire consistently, causing slippage where the wire doesn’t advance at the commanded rate. The friction can also pull the wire into a tight bend or kink near the drive rolls, creating a tangled buildup often called a “bird nest.” These feed irregularities disrupt arc stability and welding performance. While other weld defects can arise from different issues, the direct consequence of dirty liner drag is slippage and bird nesting at the drive rolls.