← Glossary

Gas Pre-Flow Time

Pre-flow time is the time shielding gas flows before the arc is struck. It ensures the weld area is free of oxygen and prevents porosity.

Physicochemical Mechanism of Action

Pre-flow time is the time shielding gas like argon or helium flows before the arc is struck. This removes oxygen molecules from the weld area, preventing porosity.

Metallurgical Relevance & Welding Risks

Too short a pre-flow time can leave oxygen in the weld zone, causing porosity and cracks. Too long a pre-flow time wastes time and slows down the process.

Workshop Practice & Instructions

The optimal pre-flow time varies by material and process, but typically ranges from 2 to 5 seconds. For high-quality processes like TIG welding, a pre-flow time of at least 4 seconds is recommended.

MetallurgieSchweißtechnik

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