What is the purpose of a gas lens in a GTAW torch, and how does it affect shielding gas usage?

• A. Heats the gas
• B. Increases gas consumption
• C. Focuses arc for better penetration
• D. Improves shielding gas coverage by producing a laminar flow

Answer: (D)

A gas lens reshapes the shielding gas flow into a smooth, laminar stream around the electrode and weld pool. This laminar flow reduces turbulence and eliminates gaps in the shielding blanket, so the weld area stays consistently protected from ambient air. With a more uniform shield, arc stability and weld quality improve, especially in tight or tricky positions. Because the shielding is more efficient, you can maintain adequate coverage with lower gas flow rates than you would need with a plain nozzle. The gas lens itself doesn’t heat the gas or focus the arc; its main purpose is to produce that steady, laminar shield around the weld.