1. fusion welding
Refers to the welding joint under the action of high temperature during welding. The state of melting. Because the welded parts are closely attached together, under the action of temperature field and gravity, the molten solutions of the two parts will be mixed without pressure. After the temperature is lowered, the melted part condenses, and the two workpieces are firmly welded together, thus completing the welding method.
2. Crimping
Pressure welding refers to a welding method in which a certain pressure is applied to the combined weldment in a heated or unheated state, so that it is plastically deformed or melted, and a metal bond is formed through recrystallization and diffusion, so that atoms on two separated surfaces are connected. There are many types of pressure welding, such as resistance welding, forging welding, contact welding, friction welding, gas pressure welding, cold pressure welding and explosive welding.
3. Brazing
It refers to the welding method that the solder below the melting point of the weldment and the weldment are heated to the melting temperature of the solder at the same time, and the gap of the solid workpiece is filled with liquid solder to connect the metals. When brazing, the oxide film and oil stain on the contact surface of the base metal should be removed first, so as to facilitate the capillary function after the solder is melted and increase the wettability and capillary fluidity of the solder. According to the different melting point of solder, brazing can be divided into brazing and soldering.
In addition, the welding process is related to the welding method and other factors, and the operation needs to be determined according to the material, brand, chemical composition, structural type and welding performance requirements of the welded parts. Determine the welding methods, such as manual arc welding, submerged arc welding, TIG welding, MIG welding, etc. There are many welding methods, which can only be selected according to the specific situation. After the welding method is determined, the welding process parameters are determined. The types of welding process parameters are different. For example, manual arc welding mainly includes: covered electrode model (or brand), diameter, current, voltage, welding power supply type, polarity connection, number of welding layers, number of welding passes, inspection method, etc.