Welded steel pipe is welded by steel, and its application space is quite large. High-quality welded steel pipes are not only corrosion-resistant and moisture-proof, but also have a long service life in use. On the one hand, the quality of welded steel pipes comes from the type of steel they choose, on the other hand, it comes from the welding process in their processing. The quality of welding technology will directly affect its quality. What are the welding processes for welding steel pipes? 1. High-frequency resistance welding uses the skin effect and proximity effect of high-frequency current to quickly heat the edge of the steel strip of the tube blank to melt it, and the molten metal is extruded under the action of the extrusion roller to realize welding. 2. Submerged arc welding is a method to realize arc welding under the protection of flux. The weld metal pool is solidified into a weld under the protection of flux coating, and the flux coating is cooled into a slag shell covering the outer surface of the weld. 3, tungsten inert gas shielded welding using pure tungsten or active tungsten (thorium tungsten, cerium tungsten, etc. ) as the electrode of inert gas shielded welding, it is transformed into tungsten inert gas shielded welding, which is abbreviated as TIG welding in English. Under the protection of inert gas, it is a welding method that uses the arc heat generated between tungsten electrode and weldment to melt the base metal and filler wire. 4. Metal inert gas inert gas shielded welding with welding wire as melting electrode. 5. CO2 gas shielded welding uses CO2 with purity greater than 99.8% as shielding gas. 6. Mixed gas shielded welding is composed of two or more gases, and the mixed gas is used as the shielding gas for gas shielded welding according to a certain proportion; Argon arc welding: gas shielded welding with argon as shielding gas. 7. Pulsed argon arc welding is argon arc welding which maintains the ionization channel of the main arc with basic current, and produces pulsed arc by periodically adding pulsed current with the same polarity and high peak value to melt metal and control droplet transition. 8, plasma arc welding with the help of water-cooled nozzle to suppress the arc, to obtain a higher energy density of plasma arc welding method. 9. In the process of hot brazing welding, a metal material with a melting point lower than that of the base metal is used as the brazing filler metal, the weldment and the brazing filler metal are heated to a temperature higher than that of the brazing filler metal and lower than that of the base metal, and the liquid brazing filler metal is used to wet the base metal, fill the connection gap, and diffuse with the base metal to realize the connection of the weldment, which is called brazing. Induction brazing is a common brazing method for composite steel. Number of views