The main uses of various types of welding flux

1.High-silicon smelting flux

According to the different MnO content, high-silicon flux can be divided into four types: high-manganese high-silicon flux, medium-manganese high-silicon flux, low-manganese high-silicon flux, and manganese-free high-silicon flux. Due to the high content of Si0 2 (> 30%), silicon can be transferred into the weld through the flux. Among them, flux containing high MnO has the effect of transferring manganese to the weld metal. When the content of SiO2 and MnO in the flux increases, the transition amount of silicon and manganese increases. The transition of silicon is related to the silicon content of the wire. When the flux contains MnO <10% (sio2 = "" mno = ""> (25 ~ 30)%, the increase of MnO has little effect on the transition of manganese. The transition amount of manganese is not only related to the content of Si02 in the flux. And it also has a lot to do with the manganese content of the welding wire. The lower the manganese content of the welding wire, the better the effect of manganese transition through the flux. Therefore, it is necessary to choose a different manganese content welding wire according to the amount of MnO in the high silicon flux.

2.Medium silicon melting flux

Because this type of flux contains a lower amount of acidic oxide Si02 and a higher amount of basic oxide CaO or MgO, it has higher alkalinity. Most medium-silicon fluxes are weakly oxidizing fluxes, and the weld metal has a lower oxygen content and therefore higher toughness. This type of flux can be used to weld alloy structural steel with appropriate welding wire. In order to reduce the hydrogen content of the weld metal and improve the cold crack resistance of the weld metal, a certain amount of FeO can be added to this type of flux. Such a flux becomes a medium silicon oxidizing flux, and is a new type of flux for welding high-strength steels.

3. Low-silicon smelting flux

It is composed of CaO, Al2O3, MgO, CaF2 and so on. This flux has basically no oxidation effect on the weld metal, and can be used to weld high alloy steels such as stainless steel and heat-strength steel with corresponding welding wires.

4.Fluorine-based sintered flux

This is an alkaline flux. It can be used for AC and DC. The welding wire is connected to the positive electrode during DC welding. The maximum welding current can reach 1200A. The weld metal has high low-temperature impact toughness. With appropriate welding wire, it can weld a variety of low-alloy structural steels for important welding products, such as boiler pressure vessels, pipes, etc. Can be used for multi-wire submerged arc welding, especially for double-sided single-pass welding of large diameter vessels.

5.Silicon calcium sintered flux

This is a neutral flux. It can be used for AC and DC. The welding wire is connected to the positive electrode during DC welding. The maximum welding current can reach 1200A. With appropriate welding wire, ordinary structural steel, boiler steel, pipeline steel, etc. can be welded. Can be used for multi-wire rapid welding, especially suitable for double-sided single-pass welding. Because it is "short slag", small diameter pipelines can also be welded.

6.Silicon-manganese sintered flux

This flux is an acidic flux, which can be used for both AC and DC. The welding wire is connected to the positive electrode during DC welding. With appropriate welding wire, it can weld low carbon steel and some low alloy steel, used for welding metal structures such as rolling stock, mining machinery and so on.

7, Aluminum titanium sintered flux (SJ501)

This is an acidic flux that can be used for both AC and DC. The welding wire is connected to the positive electrode during DC welding. The maximum welding current can reach 1200A. The flux has strong anti-porosity ability, and is not sensitive to a small amount of rust film and high temperature oxide film. With appropriate welding wire, it can weld low carbon steel and some low alloy steel structures, such as boilers, ships, pressure vessels, etc. Can be used for multi-wire rapid welding, especially suitable for double-sided single-pass welding.