Tungsten inert gas welding (TIG) is a commonly used
steel pipe welding method in the installation and construction of steel pipes in the petroleum, chemical, natural gas, shipbuilding, and other industries. It has good welding quality, high cost, and low efficiency. It is generally used for welding small-diameter important steel pipes and base welds.
Working principle of tungsten inert gas welding for steel pipes
Tungsten inert gas welding is an arc welding method that uses inert gas (argon) protection. The argon gas ejected from the nozzle creates a warm and dense gas protection layer to isolate the air during welding. In the argon laminar flow, the arc burns between the tungsten electrode and the workpiece. The heat generated by the arc is used to melt the welded part and fill the welding wire to connect the two separated metals together, thereby obtaining a firm welded joint.
Features of tungsten inert gas welding for steel pipes:
1. Argon is an inert gas that does not decompose at high temperatures, does not react with weld metal, and does not dissolve in liquid metal. Therefore, it has the best protection effect and can effectively protect the molten pool metal. It is a welding method of the highest quality.
2. Argon is a monatomic gas, which has a high-temperature secondary absorption exothermic decomposition reaction, poor conductivity, and the compression effect and cooling effect of the argon flow, which makes the arc heat concentrated, the temperature high, and the arc stability good. It can burn stably even at low current.
3. The heat of argon arc welding is concentrated, and the argon gas ejected from the nozzle has a cooling effect, so the heat-affected zone of the weld is narrow and the weld deformation is small.
4. Using argon gas to protect the weld without slag improves work efficiency, and the weld is beautiful and of good quality.
5. Argon arc welding is an open arc operation, the molten pool is well visible, easy to observe and operate, the technology is easy to master, and it is suitable for welding in various positions.
6. In addition to ferrous metals, it can be used to weld non-ferrous metals and alloy steels such as stainless steel, aluminum, and copper.