What is the definition and function of pig iron?
The reduction of blast furnace gas produced at the outlet of the fuel before combustion, this process occurred two movement: 1 rising flow of hot gas, the 1 is the landing charge flow (iron ore, coke, flux etc.). All the reaction occurred in the blast furnace gas and the opposite charge of the activities and interactions. It includes the furnace heating, evaporation, volatilization and decomposition; iron and other elements of the reduction; desulfurization slag and pig iron melt, non iron oxide charge; the formation of cementite and iron iron; furnace and gas between the heat exchange and so on, is the sum of a series of physical and chemical reactions process.
Although the principle of smelting pig iron is similar, but due to different points, smelting equipment is different, so the process is differentBlast furnace production is carried out. A generation of blast furnace (from start-up to overhaul shutdown of generation) can continue to produce a few years to 10 years. The production, from the top (usually roof is composed by Bell and hopper of modern blast furnace is the valve bell and bell less top) constant load of iron ore coke, flux, from the lower part of blast furnace tuyere blowing hot air, is injected into the oil, coal or natural gas. In the iron ore into blast furnace, are important compounds of iron and oxygen. Under high temperature, coke and injection of carbon materials and carbon monoxide will usurp natural combustion, iron ore the oxygen in the iron, this process is called reduction. Iron ore smelting reduction reaction through the reduction of iron, iron released from the taphole. Ash gangue, coke and iron ore were blowing in and in furnace limestone flux generated by combination of slag from the taphole and slag outlet The gas is discharged from the top of the furnace and is used as industrial gas after dust removal. A modern blast furnace can also use the high pressure at the top of the furnace to generate electricity with some of the derived gas
Carbon steel-making pig iron mainly exists in the form of iron carbide, the white section, which is also called white iron. This iron performance hard brittle, generally used as raw material for steelmaking.Cast iron in carbon flake graphite form exists, its fracture is gray, also called gray. All because graphite is soft, with lubrication, so the cast iron has good abrasion resistance, cutting and casting performance. But it is not anti digital strength, so it can not be forged, can only be used to create a variety of castings. Such as a variety of machine tool bed casting base, iron pipes and so on.Ductile iron to carbon in the form of spherical graphite, which is far better than the mechanical properties of gray cast iron and close to steel, it has excellent casting, machining and wear-resistance, has certain elasticity, widely used in gear, crankshaft, piston and other building and a variety of advanced casting machine parts, Mike plug.In addition, there is a special high silicon, manganese, nickel or other elements of pig iron, called alloy pig iron, such as ferrosilicon, ferromanganese, etc., often used as raw material for steelmaking. Adding certain alloy iron in steel-making, can improve the performance of steel
Pig iron is an alloy of iron and carbon carbon content more than 2%, pig iron carbon content is generally in 2%--4.3%, including C, SI, and Mn, S, P and other elements, is the use of iron ores in blast furnace products. According to different forms of carbon in pig iron, and can be divided into pig iron, cast iron and steel ball ductile cast iron and other types.Pig iron performance: pig iron is strong and hard, wear-resisting and casting good, but pig iron is crisp, can not forge
