The molten steel is injected into the mold through the ladle and solidified to form a steel ingot. After the molten steel is smelted in the steelmaking furnace, it must be cast into a certain shape of the ingot or billet for processing. The process of casting a steel ingot by a mold is simply referred to as an ingot.
Steel ingots are still the main raw material for rolling steel production. The quality of the ingot, the condition of the ingot type and its weight play a very important role in rolling steel production. In the steel rolling production, in addition to various types of roughing mills, steel ingots can be used as raw materials. Some special-purpose rolling mills and some medium-thick plate mills also use steel ingots as raw materials. In many local small and medium-sized enterprises, the mills for rolling mills also use small steel ingots as raw materials. . The selection of ingots is mainly to correctly select the type of ingot, its weight, and the shape and size of the section.
Steel ingots are widely used, and can be classified into the following categories according to the types of products that are forged and rolled.
Power steel includes nuclear power, thermal power, wind power, hydropower and other steel.
Nuclear power: large components such as evaporators, main pipes, core support plates, elbow plates and low-voltage rotors of generator sets, except for high strength, high toughness and high homogeneity. It also requires nuclear radiation resistance, and is made of electroslag remelted steel ingots with an ingot weight of 715t.
Hydropower: Generator rotors, bases, ship lock gates, etc. for large hydroelectric power stations require high strength, high toughness and high cleanliness.
Thermal power: steam drums, generator bases, turbine generator rotors, etc. of supercritical thermal power generators require high temperature strength, high cleanliness and creep resistance.
Wind power: Used in the manufacture of bases, poles and wind turbine shafts.
Mechanical manufacturing steel
The machinery manufacturing industry is a large user of steel ingots. In particular, China has become a major machinery manufacturing country in the world. Large-scale machinery not only needs to meet domestic demand, but also needs large-scale exports. Among them, large-scale mine crushers, ball mills, large blast furnace shells, converter support rings, rotating shafts and transmission systems, wide and thick plate mill work rolls, backup rolls and universal joint shafts, main motor shafts, seamless steel tube mills Floating mandrels, mandrel bars and other types of rolling mill rolls, bearings, bearing blocks, etc. are all forged from steel ingots; the same is true for excavator buckets, shovel arms, crane booms, etc. in large mining machinery. The figure below is 5000~5500mm wide
The support roller of the plate mill has a diameter of Φ2200~2400mm and a weight of 240t.
High-rise building steel
With the development of the construction industry, high-rise steel structures emerge in an endless stream, such as the Burj Khalifa and the Shanghai Center. For the purpose of earthquake resistance, wind protection and fire prevention, high-rise buildings of more than 200m are mostly made into the main frame of steel structure. The structure can be made of special thick plate rolled from steel ingots. It is made by cutting and welding, and requires high strength, shock resistance and Z. To performance.