Desulfurization process of carbon steel elbow

　　Desulfurization in oxygen converter is difficult and uneconomical. In recent years, the supply of high-quality metallurgical coke is insufficient, the sulfur content of coke is the highest, and the sulfur content of heavy oil injected to strengthen blast furnace smelting is also high. As a result, the quantity and cost of low sulfur molten iron meeting the steel-making requirements are becoming more and more problematic. The practice has proved that it is a good way to solve the above contradiction to take off the hot metal outside the furnace between the blast furnace and the converter.

　　It can improve the technical and economic indexes of iron making and carbon steel elbow at the same time. It is particularly important to simplify the operation of converter and realize automatic control. It is developing rapidly in many countries. The basic principle of desulfurization outside the furnace is the same as that of bowl removal inside the furnace. That is, use elements or compounds with greater affinity to sulfur than iron and sulfur to convert iron sulfide into more stable sulfide that is rarely or completely insoluble in molten iron; At the same time, good kinetic conditions are created to accelerate the diffusion of sulfur in molten iron to the reaction area and expand the reaction area between desulfurizer and molten iron. ASTM 440 is named high strength carbon steel elbow.

　　Including Mn Cu high strength low alloy steel profiles, plates and bars. It is mainly used for riveting or bolting bridges and buildings. Welding is generally not appropriate. However, the material can also be welded after certain measures are taken. Due to the minimum content of 0.2%cu, its atmospheric corrosion resistance is about twice that of carbon structural steel without Cu. The minimum yield strength of steel plate with thickness below 19mm shall be 345mpa.