1. What is flux cored welding wire?
A kind of welding wire made by rolling a thin steel strip into a round steel tube and simultaneously filling it with a certain amount of powdered medicine.
2. Why is the flux cored welding wire protected with CO2 gas?
There are two types of flux-cored welding wire in terms of protection: the core gas shielded welding wire and the drug core self-protecting welding wire. The core gas shielded welding wire is generally protected by CO2 gas, which belongs to the combined form of gas and slag protection. The weld is formed well and the overall mechanical performance is high.
3. Why does the flux-cored weld hole have an indentation blowhole?
Because the flux-cored wire is a tubular wire wound from a thin steel strip, it belongs to a seamed wire. Moisture in the air can invade the core through the gap, and the flux is wet (not dryable), resulting in indentation pores in the weld.
4. Why are there technical requirements for the purity of CO2 gas?
General CO2 gas is a by-product of chemical production. Its purity is only about 99.6%. It contains trace amounts of impurities and water, which can cause defects such as porosity in welds. The welding of important products must use CO2 purity ≥ 99.8% of the gas, weld porosity is small, low hydrogen content, crack resistance is good.
5. Why is there a high technical requirement for argon purity?
Currently, there are three types of argon on the market: general argon (about 99.6% pure), pure argon (about 99.9% pure), high-purity argon (purity 99.99%), the first two kinds of weldable carbon steel and stainless steel, and welded aluminum. Non-ferrous metals such as aluminum alloys, titanium, and titanium alloys must be made of high-purity argon; the welds and heat-affected zones must not be oxidized to be welded.
