Shielding Gas Monitoring

Physical-Chemical Mechanism of Action

Shielding gas monitoring controls the amounts and composition of gases like argon or helium in the molten pool. These gases protect the metal from oxidation by removing oxygen from the surroundings.

Metallurgical Relevance & Welding Risks

Without proper monitoring, too much oxygen can enter the process, leading to oxidation of the molten pool. This can cause porosity and reduced mechanical properties of the weld. On the other hand, insufficient gas supply can lead to too rapid cooling and thus to glass-hard, crack-prone martensite.

Workshop Practice & Action Guidelines

Make sure the shielding gas flow is constantly monitored. The gas amount should be 10-20 l/min per kg of metal. Use gas analysis to check the oxygen concentration in the gas line; it should be below 5 %. If deviations occur, correct the gas supply and check the shielding gas equipment.