Welding Process Guide
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Preheat and Interpass Temperature with Gas Considerations

Preheat and interpass temperature control prevents cracking while affecting gas flow requirements - higher temperatures reduce gas density requiring flow rate adjustments. Monitor temperatures with infrared thermometers and increase gas flow 10-15% for preheated applications above 150°C.

Temperature Control Parameters

  1. Preheat Requirements. 150-200°C for thick carbon steel, 100-150°C for stainless steel. Use propane torches or induction heating.
  2. Gas Flow Adjustment. Increase flow 10-15% when welding on preheated materials due to reduced gas density at elevated temperatures.
  3. Interpass Control. Maintain 150-250°C interpass temperature. Monitor with temperature indicating crayons or infrared thermometers.
Temperature Stable

CORGON® 18 (Ar + 18% CO2)

Why CORGON® 18 stable at temperature: Consistent performance across temperature ranges encountered in preheated welding applications. Maintains proper gas coverage despite thermal effects.