The welding core is the metal core of the electrode. In order to ensure the quality of the weld, there are strict regulations on the content of various metal elements in the weld core. In particular, there are strict restrictions on harmful impurities (such as sulfur and phosphorus), and the quality of the weld core metal should be better than that of the base metal. Arc welding cannot be carried out on a smooth rod without a coating. This is because the arc stability is very poor, splashing is very large, and the weld is not well formed. After long-term practice, it is gradually found that the performance of the electrode is greatly improved by coating the welding core with some mineral raw materials (i.e. electrode coating). (1) Ensure stable arc combustion, so that the welding process is normal. (2) Using the gas produced after the drug skin reaction, protect the arc and the molten pool, prevent the harmful gases in the air (such as nitrogen, oxygen, etc.) from invading the molten pool, such as these gases will cause cracks and pores in the welding material, so that the welding can not achieve the ideal effect. (3) After the drug skin is melted, slag is formed, which covers the weld surface to protect the weld metal, make the weld metal slowly cool, help the gas escape, prevent the generation of pores, and improve the structure and performance of the weld. (4) After melting, various metallurgical reactions will be carried out, such as deoxygenation, sulfur removal, phosphorus removal, etc., so as to improve weld quality and reduce alloying element burning loss.
Hot dip galvanizing is dipped in zinc liquid melted by heating, with fast production speed and thick but uneven coating. The market allows a low thickness of 45 microns and a high of more than 300 microns. The color is dark, the consumption of zinc metal is much, the formation of infiltration layer with the matrix metal, the corrosion resistance is good, and the outdoor environment of hot dip galvanized can be maintained for decades. Application range of hot dip galvanizing: because the coating is thicker, hot dip galvanizing has better protective performance than electric galvanizing, so it is an important protective coating for iron and steel parts in harsh working environment. Hot-dip galvanized products are widely used in chemical equipment, petroleum processing, Marine exploration, metal structure, power transmission, shipbuilding and other industries, in the field of agriculture such as sprinkler irrigation, greenhouse and construction industry such as water and gas transmission, wire casing, scaffolding, Bridges, highway guardrail and other aspects, has been widely used.
The reason why there are black spots in wire mesh welding is that the action of wire feeding should be timely filled in the melting time, and the development should be appropriate. There is no argon gas, long burning, large current, long distance, blunt tungsten needle and high molten pool temperature are the fundamental reasons for blackening. Continuous burning, is about active welding machine energy selection, machine welding will appear black spots.
4. When nothing happens, touch the cage in your hand. If your hands are dry, wipe them with an oilcloth and plate them. There are various ways to protect the structure of the cage from damage. The plate cage can improve the surface finish of the cage, and can eliminate the internal stress of part of the bird cage structure, so that the cage structure is gradually stable, reduce the possibility of deformation.
Cold galvanized is in the plating tank through the current unidirectional zinc gradually plated on the metal surface, production speed is slow, uniform coating, thin thickness, usually only 3-15 microns, bright appearance, poor corrosion resistance, generally a few months will rust. Compared with electrogalvanizing, hot galvanizing has lower production cost and less impact on the environment than electroplating.
The use of steel mesh saves a lot of on-site binding and construction site, can end civilized construction, advance the quality of steel structure engineering. Because the steel mesh is prefabricated in the factory, there is no need for site reprocessing, and there is no need for steel chips, because the construction cycle is shortened, and the cost of lifting machinery is reduced.
Iron products are common metal products in life. Iron products appear everywhere in our life, but there is a big problem in using iron products. Iron products will rust, and when rust occurs, it will affect the use and appearance of iron products. Adding non-metallic coating: clean, dry and coat the surface of iron and steel products with a layer of protective materials, such as oil, mineral grease, rust-proof grease, plastic and lacquer.
There is good toughness and elasticity, simply put, can be easily made into various shapes, and zinc as a coating is silver, very beautiful. Such characteristics make hot dip galvanized wire handicrafts, woven screen and other aspects have also been applied. Hot plating wire selection of high quality low carbon steel rod processing, is the selection of high quality low carbon steel, after drawing molding, pickling rust removal, high temperature annealing, cooling and other processes.
