How to Prevent Porosity Defects in 3D Welding Tables?

1. Material Cleaning and Drying
Welding Material Treatment: Before use, check that the electrode coating is intact and avoid moisture or damage; alkaline electrodes should be dried before storage in a heated container and used immediately after removal.
Base Metal Cleaning: Before welding, thoroughly remove oil, rust, oxides, and other impurities from the bevel and 10-15mm on both sides until the metal luster is exposed.
2. Optimization of Process Parameters
Current and Speed: Use appropriate welding current, voltage, and speed to avoid excessive or insufficient current, or excessive speed leading to rapid cooling of the molten pool.
Arc Control: Alkaline electrodes require short-arc welding (DC reverse polarity) to reduce the chance of air entering the molten pool.
3. Environmental and Protective Measures
Wind and Moisture Protection: When working outdoors, set up windbreaks to avoid welding in strong winds or rainy weather; for argon arc welding, ensure the purity of argon gas (≥99.95%) and moderate flow rate.
Protective Gas: Use protective gases such as argon and carbon dioxide to ensure that the molten pool is isolated from the air.
4. Operating Procedures
Welder Skills: Maintain a stable arc, correctly master the operating essentials of arc starting, welding, and arc extinguishing, and avoid arc deflection.
Preheating and Slow Cooling: Preheat thick plates or high-carbon steel materials to reduce the cooling rate and promote gas escape.
5. Quality Inspection and Repair
Real-time Inspection: After welding, check for porosity visually or by non-destructive testing; defects exceeding the standard require grinding and re-welding.
Continuous Improvement: Analyze the causes of porosity (such as gas source, molten pool fluidity), and optimize process parameters.