Production process of Q345B low alloy angle steel.
1. Introduction. Q345B low alloy angle steel is a common building structure material, with excellent mechanical properties and corrosion resistance, widely used in bridges, construction, electric power and other fields. This article will introduce the production process of Q345B low-alloy angle steel in detail, including smelting, continuous casting, rolling, straightening and other links, in order to provide reference for related enterprises.
2. Smelting. The smelting of Q345B low-alloy angle steel is smelted by electric furnace or converter, and the main process includes melting, oxidation, reduction and pouring stages. In the melting stage, the raw material (molten iron, scrap) is heated to the melting point and then meltedIn the oxidation stage, the impurities in the melt are oxidized by adding an oxidizing agent such as oxygen or iron ore to the melt, and oxides are formed at the same timeIn the reduction stage, reducing agents such as coke and limestone are added to the melt to reduce the alloying elements such as chromium and nickel in the melt to form low-alloy steelIn the pouring stage, molten steel is poured into the ingot mold, cooled and solidified to form the ingot.
3. Continuous casting. Continuous casting is the process of continuously pouring molten steel into a casting billet of the desired shape and size. The continuous casting of Q345B low-alloy angle steel adopts a vertical continuous caster, and the main process includes the stages of molten steel heating, pouring, crystallization and cutting. In the molten steel heating stage, the molten steel is heated to the desired temperature;In the pouring stage, the molten steel is poured into the caster for pouring;In the crystallization stage, the cooling rate and temperature are controlled to form the desired shape and size;In the cutting stage, the billet is cut to the required length.
Fourth, rolling. Rolling is the process of plastically deforming a continuous casting billet through a rolling mill to form a steel of the desired shape and size. The rolling of Q345B low-alloy angle steel is carried out by a large rolling mill for multi-pass rolling, and the main process includes heating, rolling, cooling and straightening stages. In the heating stage, the continuous casting billet is heated to the desired temperature;In the rolling stage, the continuous casting billet is deformed into the desired shape and size of steel by multiple passesIn the cooling phase, the steel is cooled to the desired temperature by controlling the cooling rate and temperatureIn the straightening stage, the steel is straightened to make its surface flat and smooth.