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How many common welding types are there? How to choose welding materials?

There are several common welding types? How to choose welding materials?
How to choose welding materials correctly, we must first consider the physical properties, mechanical properties and chemical composition of the welding materials, as well as working conditions and performance.

Physical properties, mechanical properties and chemical composition of welding materials
1. For dissimilar steel welded joints between low carbon steel and low alloy steel, most of the Corresponding welding materials for steels with lower strength grades.
2. When the chemical composition of the base metal contains high levels of harmful impurities such as phosphorus, carbon, and sulfur, a welding material with stronger crack resistance should be selected. Such as: low-hydrogen welding materials, etc.
3. For the welding of heat-resistant steel and stainless steel, in addition to considering the strength, we must also consider that the main chemical composition of the weld metal is close to the chemical composition of the base metal.
4. For welding of structural steel, generally considering the principle of equal strength, select welding materials that meet the requirements of mechanical properties of the joint.

Considering the working conditions and performance of welding
1. For welding at high or low temperature, it is necessary to select welding materials that can ensure high or low temperature mechanical properties.
2. When welding is subjected to dynamic load and impact load, in addition to ensuring the yield strength, tensile strength, plasticity and impact toughness have higher requirements. Need to choose low-hydrogen type materials.
3. When welding is working in corrosive media, we must distinguish the concentration, quality, corrosion type and working temperature, so as to choose the appropriate stainless steel welding material.
4. When welding is working under abrasion conditions, we have to distinguish between general wear and impact wear, intermetallic wear or abrasive wear, wear at room temperature or high temperature. And choose suitable welding materials.

Classification of welding types
At present, welding is mainly divided into argon welding, CO2 welding, oxygen cutting, electric welding, gas shielded welding, and self-shielded welding.
Argon welding
The main welding materials used for argon welding are: argon welding machine (required) argon welding gun (including cloth cover, small gas tube*2 main line gun head tungsten needle clamp porcelain nozzle copper head) mainly using argon welding wire ( The more common models are 308L316……), tungsten needles (generally ***175), argon welding caps, and stainless steel electrodes.

CO2 welding
The main welding materials used for CO2 welding are: CO2 welding machine, CO2 welding torch, CO2 front gun body elbow pipe insulator connector contact tip, CO2 welding wire, CO2 portable welding cap.

Gas shielded welding
Gas shielded welding mainly refers to welding by gas shielding. As long as it is a welding method that uses gas to separate the welding area from the air, it is generally fed continuously with welding wire.

Self-shielded welding
Self-shielded welding refers to a welding method in which no external protective medium is needed during welding, and the flux core of the welding wire is used for protection.

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