1. what is the welding material? What does it include?
Answer: welding materials include welding rod, welding wire, flux, gas, electrode, liner and so on.
2. what is welding wire?
Answer: when welding, it is used as filler metal and conductive wire at the same time - called welding wire. There are two kinds of solid wire and flux cored wire. The common type of solid wire is ER50-6 (grade: H08Mn2SiA).
3. why does the MAG welded joint have higher impact toughness than the CO2 welded joint?
Answer: when MAG is welded, the active gas is only 20%, the alloy element transition coefficient of the welding wire is high, and the impact toughness of the weld is high. The active gas of CO2 welding is 100%, and the manganese and silicon alloy elements in the welding wire deoxidize, the transition coefficient of the alloy elements is slightly lower, and the impact toughness of the weld is not as high as that of the MAG welding. For example, the impact toughness of Tangshan Kobelco MG-51T welding wire (commensurate with ER50-6) at room temperature is MAG:160J: CO2:110J.
4. what is a flux cored wire?
Answer: a kind of welding wire made of thin steel strips rolled into circular steel pipes and filled with certain components of powder.
5. why is the flux cored wire protected by CO2 gas?
Answer: according to the protection way, there are two types of flux cored wire: flux cored wire and flux core self shielded welding wire. The gas core welding wire is usually protected by CO2 gas. It belongs to the joint form of gas slag protection, with good weld shape and high comprehensive mechanical function.
6. why does the surface of the flux cored wire weld indentation pores?
Answer: because the flux cored wire is a tubular welding wire made of thin steel strip, it belongs to the seam welding wire; the moisture in the air will invade the drug core through the crevice, and the flux is moist (unable to dry), causing the weld to have the indentation hole.
7. why is there a technical requirement for the purity of CO2 gas?
Answer: General CO2 gas is a byproduct of chemical production. Its purity is only about 99.6%, which contains trace impurities and moisture. It will bring holes and other defects to the welds. For welding important products, we must choose CO2 with a purity of more than 99.8%. The weld porosity is low, the hydrogen content is low, and the crack resistance is good.
8. why is there a high technical requirement for the purity of argon gas?
Answer: at present, there are three kinds of argon in the market: Universal argon (purity of about 99.6%), pure argon (about 99.9%), high purity argon (purity 99.99%), the first two kinds of welded carbon steel and stainless steel. Welding aluminum and aluminum alloy, titanium, titanium alloy and other non-ferrous metals must be high pure argon; avoid the weld and heat affected zone can not be oxidized to enter. Line welding.
9. why do TIG welding nozzles have many sizes?
Answer: there are five types of nozzles with 4 - 8. The welded carbon steel can be used for 4 - 5 nozzles. The welding stainless steel and aluminum and aluminum alloy should choose the large nozzle of 6 - 7 to strengthen the protection range of the weld and the heat affected zone. For welding nonferrous metals such as titanium and titanium alloys, the larger nozzles 7 to 8 should be used to prevent the weld and heat affected zone from being oxidized.
10. what is an acid electrode?
Answer: the electrode contains many acid oxide electrodes, such as junction 422 (E4303), junction 502 (E5003) and other AC and DC welding electrodes.
11. what is an alkaline electrode?
Answer: there are a lot of electrodes containing alkaline fluoride and fluoride, such as knot 507 (E5015), knot 506 (E5016), etc.
12. what is cellulose electrode (downward vertical welding)?
Answer: the electrode contains many organic electrodes, and the pipe and sheet structure is vertical welding.
"1", such as E6010 (E4310, J425G), is used for primer welding, hot welding and filler welding.
"2" E8010 (commensurate with E5511 and J555) is used for hot welding, filler welding and cover welding.
Generally, the weld surface is covered by low hydrogen down welding electrode, and E7048 (J506X) is neat and beautiful.
13. why should the pre welding rod be strictly dried?
Answer: electrodes tend to deteriorate the process due to moisture absorption, resulting in unstable arc and spatter, and easily produce indignant holes, cracks and other defects. Therefore, the welding rod must be strictly dried before use. The drying temperature of the ordinary acid electrode is 150--200 C, time 1 hours, the drying temperature of alkaline electrode is 350--400 C, time 1--2 hours, after drying in the 100--150 centigrade incubator, along with the use.