Application overview Hot-rolled ribbed steel bars are widely used in high-speed railways, nuclear power plants, Olympic venues, the Three Gorges Water Control Project and other national key projects and some landmark buildings. Round steel is widely used in ships, vehicles, aircraft, railways, bridges, pressure vessels, machine tool parts. Hot rolled round bar After hot rolling, the section is usually round, and the finished steel bar has a smooth surface.Hot-rolled steel bars in my country can be divided into four grades according to their strength: First-class steel bar: widely used, it can be used as the main stress steel bar of small and medium-sized reinforced concrete structures, the stirrups of components, and the tie rods of steel-wood structures. Wire rod can also be used as raw material for cold drawn low carbon steel wire and double steel rod. Primary reinforcement: widely used in large and medium-sized reinforced concrete structures, such as bridges, dams, port projects and main reinforcement of building structures. Secondary steel bars can also be used as prestressed steel bars for building structures after cold drawing. Eigenvalue The quantile value corresponding to the specified probability in infinite trials. Reinforcing bars are classified into 235 and 300 grades according to the characteristic value of yield strength. HPB235 hot-rolled round bar is calculated according to HPB+yield strength HPB—hot-rolled round bar Chinese language rebar. Hot-rolled ribbed bars and hot-rolled round bars are widely used in various building components and have good compressive and tensile properties, excellent cold bending properties and good welding properties. The nominal diameter of rebars ranges from 6mm to 22mm. The nominal diameters of steel bars recommended in this standard are 6mm, 8mm, 10mm, 12mm, 16mm and 20mm.