There are 4 types of scrap steel. The details are as follows:
1. Unified scrap iron refers to scrap steel, pig iron, thin and thick raw and cooked scrap iron and steel mixed together. ?
2. Mechanical scrap iron refers to scrap steel from scrap machine tools.
3. The stamped iron trim refers to the trimmings after punching the steel plate price. ?
4. Motor iron refers to scrap steel after dismantling used motors.
1. Scrap steel refers to steel scraps that do not become products during the production process of steel plants (such as trimmings, trimmings, etc.) as well as steel materials in equipment and components that are scrapped after use. The composition is steel. It’s called scrap steel; the stuff that’s made of pig iron is called scrap iron, collectively called scrap steel. At present, the total amount of scrap steel produced in the world every year is 300-400 million tons, accounting for about 45-50% of the total steel production, of which 85-90% is used as raw material for steelmaking, and 10-15% is used for casting, ironmaking and recycled steel.
2. The scrap steel generated during the production process of steel plants is called "return scrap steel", "self-produced scrap steel" or "recycled scrap steel". Its carbon content is generally less than 2.0, and its sulfur and phosphorus content are not more than 0.05. Scrap steel comes in various shapes due to different circumstances of its production. Its performance is basically the same as that of the finished product from which such scrap steel is produced. However, it is also affected by aging effectiveness, fatigue and other factors, and its performance is reduced. The self-produced scrap steel of ordinary steel plants is about 15 to 25% of the steel output; the amount of special steel plants is 30 to 50%.
3. Scrap steel is mainly produced in steelmaking workshops, steel casting workshops and cold and hot processing workshops of steel. With the development of steel production technology, the steel yield rate has increased, and the proportion of self-produced scrap steel in steel production has been on a downward trend. Scrap steel generated during the manufacturing process of steel products and machinery accounts for about 20 to 25% of the total scrap steel. It is mainly the cut ends, tail cuts, chips, leftovers, etc. of steel materials. Various scrap equipment, steel structural parts, "scrapped" locomotives, vehicles, rails, cars, ships, tools, appliances, etc. also produce a large amount of "depreciated scrap steel". It accounts for about 25-30% of the total scrap steel in industrially developed countries and 1-1.5% of the total steel input in society. China currently produces about 3 million tons of depreciated steel scrap every year. Scrap steel for daily necessities such as cans, furniture and appliances, etc., is called "social scrap steel" or "garbage scrap steel", and the amount is sometimes as high as 1% of the steel input. In addition, there are scrap steel recovered from slag, accumulated scrap steel blocks, salvaged sunken ships, etc. The sources are quite complex.
4. Scrap steel crushing technology The methods for crushing large-sized and special-shaped scrap steel that are difficult to enter the furnace, transport, and sort include: gas cutting, drop hammer, blasting, shearing, and shredder Broken and other methods. Due to the different scrap steel resources, uneven pile density and large composition differences, this in turn has an impact on the development of electric furnace steel. Therefore, the pretreatment of scrap steel can improve the performance and input-output ratio of steel products.
5. The geographical distribution of my country’s scrap steel resources is also unbalanced. More than 80% of the country’s scrap steel resources are distributed in Beijing, Tianjin, Shanghai, Guangdong, Liaoning, Heilongjiang, Hebei, Shanxi, Shandong, Hubei, and Sichuan And Jiangsu, the 12 provinces and cities where industrial and mining enterprises are concentrated and the population is relatively dense; other areas generate less than 20 scrap steel resources due to poor geographical conditions and small populations.
Reference material: Chengdu Iron and Steel Network "What kinds of scrap iron are there? How to distinguish them, what are the different types of scrap iron" web link