Welding Process Guide
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Joint Preparation and Fit-up for Optimal Gas Coverage

Proper joint preparation with appropriate root opening and bevel angles ensures gas can reach all areas of the weld zone for complete protection. V-groove joints need 60-75° included angle for adequate gas access, while tight fit-up prevents excessive gas consumption through large gaps.

Joint Design for Gas Coverage

  1. Root Opening Control. Maintain 2-3mm root opening maximum. Larger gaps waste gas and risk lack of fusion.
  2. Bevel Angle Optimization. Use 30-37.5° bevel angles (60-75° included) for V-groove joints to allow gas penetration.
  3. Access Planning. Design joints to allow proper torch angle and gas nozzle positioning.
Joint Optimized

FORMIER® for Root Protection

Why FORMIER® essential for tight joints: Backing gas becomes critical when joint access is limited and front-side gas coverage may be compromised by joint geometry.