Then, the molten steel is poured into a continuous casting machine for solidification.
In this way, semi-finished products as we know them are produced. These semi-finished products can be flat steel ingots with rectangular cross section or block steel or billet with square cross section. Are used to make the blank of the final product.
Finally, these semi-finished products are deformed or rolled into final products. Some of them must undergo heat treatment, which is called "hot rolling". Subsequently, more than half of the hot rolled steel sheet is rolled again at ambient temperature (so-called "cold rolling"). Then, it can be coated with a protective material against corrosion.
1- sintering
Iron ore is prepared in the sintering workshop. Iron ore is crushed into standardized particles, sintered or bonded together. The sintered iron ore is crushed and added to the blast furnace in the form of coke and ore alternately. Coke is a solid residue distilled from carbon-rich coal, which is easy to burn.
2 blast furnace
In a blast furnace, iron is extracted from iron ore. Solid ore and coke are added from the top of the blast furnace, and the hot gas (1200℃) at the bottom of the blast furnace makes the coke with almost 100% carbon content start to burn. This will produce carbon oxides, which will reduce iron oxides through the oxygen removal process, thus separating iron. The heat generated by combustion melts iron and gangue (a collection of minerals in ore) into liquid. Gangue, because it is light, will float to the surface of molten iron, which is called "pig iron". Slag is the residue produced by melting coal gangue, which can be used for other industrial purposes, such as paving roads or producing cement.
3- Coking furnace
Coke is a combustible substance obtained by dry distillation (that is, evaporation of unwanted components) of coal in a coking furnace. Coke is almost pure carbon, with porous structure and strong crushing resistance. Coke is burned in the blast furnace to provide the heat and gas needed to melt iron ore.
4 converter
Pig iron is converted into steel in an oxygen-blown converter. Pour molten pig iron on a layer of iron filings. Unwanted substances such as carbon and residue will be burned by injecting pure oxygen, thus producing crude steel. Then, skim off the residue or slag. Then the crude steel (so called because it needs further refining) is poured into the bucket.
Five arc furnaces
It can be selected but untreated scrap iron (such as old machine parts) or standard scrap iron with iron content of at least 92% after screening and crushing. Scrap iron melts in an electric arc furnace. This produces molten steel, which is classified as pig iron after refining. Scrap iron includes waste steel packaging materials, building materials, machine and vehicle parts, or waste pig iron and steel produced in steelmaking process or steel processing equipment. For each different steel grade, raw materials must be carefully selected. This choice depends on the type of "impurities" that any metal or ore in scrap iron may contain. The magnetic "waste hopper" of electric arc furnace sends raw materials into the furnace. The melting process is driven by a powerful arc, which "jumps" between the electrode and the raw materials in the furnace. Residue or slag will be recovered from the furnace. The final product is molten steel, which is now sent to ladle furnace and classification equipment.
6- refining
Refining (decarbonization) and adding chemical additives need to be carried out in a vacuum sealed container. With the help of inert gas argon, steel rotates between refining barrel and container. This process can adjust the chemical composition of steel with high precision to obtain special steel.
7- continuous casting machine
Shown here is a flat ingot casting. Molten steel is continuously poured into a bottomless mold. When drawing the mold, the steel begins to contact with the water-cooled inner wall of the crystallizer and begin to solidify. Then, while continuously cooling, the cast metal is pulled down by a series of rollers. When it reaches the end point, the steel has completely solidified and is immediately cut to the required length.
Eight-high mill
Convert the blank into the final product. At this time, the flat ingot is rolled into a thin plate. The flat ingot is first reheated in the furnace. This makes it more malleable and promotes stretching and forming. Then, the blank is "slimmed down" by the roller of the broaching machine, or it is gradually thinned.
Raw materials-iron ore or scrap iron, depending on the process-are first melted into molten steel. Blast furnace must be used in steelmaking with ore as raw material, and arc furnace is used in the process with scrap iron as raw material.
Then, the molten steel is poured into a continuous casting machine for solidification.
In this way, semi-finished products as we know them are produced. These semi-finished products can be flat steel ingots with rectangular cross section or block steel or billet with square cross section. Are used to make the blank of the final product.
Finally, these semi-finished products are deformed or rolled into final products. Some of them must undergo heat treatment, which is called "hot rolling". Subsequently, more than half of the hot rolled steel sheet is rolled again at ambient temperature (so-called "cold rolling"). Then, it can be coated with a protective material against corrosion.
1- sintering
Iron ore is prepared in the sintering workshop. Iron ore is crushed into standardized particles, sintered or bonded together. The sintered iron ore is crushed and added to the blast furnace in the form of coke and ore alternately. Coke is a solid residue distilled from carbon-rich coal, which is easy to burn.
2 blast furnace
In a blast furnace, iron is extracted from iron ore. Solid ore and coke are added from the top of the blast furnace, and the hot gas (1200℃) at the bottom of the blast furnace makes the coke with almost 100% carbon content start to burn. This will produce carbon oxides, which will reduce iron oxides through the oxygen removal process, thus separating iron. The heat generated by combustion melts iron and gangue (a collection of minerals in ore) into liquid. Gangue, because it is light, will float to the surface of molten iron, which is called "pig iron". Slag is the residue produced by melting coal gangue, which can be used for other industrial purposes, such as paving roads or producing cement.
3- Coking furnace
Coke is a combustible substance obtained by dry distillation (that is, evaporation of unwanted components) of coal in a coking furnace. Coke is almost pure carbon, with porous structure and strong crushing resistance. Coke is burned in the blast furnace to provide the heat and gas needed to melt iron ore.
4 converter
Pig iron is converted into steel in an oxygen-blown converter. Pour molten pig iron on a layer of iron filings. Unwanted substances such as carbon and residue will be burned by injecting pure oxygen, thus producing crude steel. Then, skim off the residue or slag. Then the crude steel (so called because it needs further refining) is poured into the bucket.
Five arc furnaces
It can be selected but untreated scrap iron (such as old machine parts) or standard scrap iron with iron content of at least 92% after screening and crushing. Scrap iron melts in an electric arc furnace. This produces molten steel, which is classified as pig iron after refining. Scrap iron includes waste steel packaging materials, building materials, machine and vehicle parts, or waste pig iron and steel produced in steelmaking process or steel processing equipment. For each different steel grade, raw materials must be carefully selected. This choice depends on the type of "impurities" that any metal or ore in scrap iron may contain. The magnetic "waste hopper" of electric arc furnace sends raw materials into the furnace. The melting process is driven by a powerful arc, which "jumps" between the electrode and the raw materials in the furnace. Residue or slag will be recovered from the furnace. The final product is molten steel, which is now sent to ladle furnace and classification equipment.
6- refining
Refining (decarbonization) and adding chemical additives need to be carried out in a vacuum sealed container. With the help of inert gas argon, steel rotates between refining barrel and container. This process can adjust the chemical composition of steel with high precision to obtain special steel.
7- continuous casting machine
Shown here is a flat ingot casting. Molten steel is continuously poured into a bottomless mold. When drawing the mold, the steel begins to contact with the water-cooled inner wall of the crystallizer and begin to solidify. Then, while continuously cooling, the cast metal is pulled down by a series of rollers. When it reaches the end point, the steel has completely solidified and is immediately cut to the required length.
Eight-high mill
Convert the blank into the final product. At this time, the flat ingot is rolled into a thin plate. The flat ingot is first reheated in the furnace. This makes it more malleable and promotes stretching and forming. Then, the blank is "slimmed down" by the roller of the broaching machine, or it is gradually thinned.