Forming Gas Displacement Flow
Purging gas displacement flow is a laminar air flow that removes oxygen from closed cavities and replaces it with shielding gas. It minimizes turbulence and gas consumption.
Physicochemical mechanism of action
The purging gas displacement flow is a controlled laminar air flow that removes oxygen from closed cavities and replaces it with shielding gas. The laminar flow prevents turbulence and minimizes gas consumption.
Metallurgical relevance & risks when welding
Insufficient or faulty purging gas displacement flow can lead to oxygen contamination of the weld, which can cause corrosion and cracks in the metal. This increases the risk of hot cracking and reduces the service life of the components.
Workshop practice & instructions
To ensure effective purging gas displacement flow, the air flow must be kept laminar. This requires a proper setup of the shielding gas supply system with a suitable fan and a gas filter. The air flow direction should be parallel to the purging surface to ensure maximum oxygen removal. A typical air flow rate is 0.5 to 1 m/s.