Application of ordinary carbon steel

It is mainly used to make carbon structural steel for engineering structural parts. It is generally used in the supply state, and the content of sulfur and phosphorus in steel is high, allowing up to 0.050% and 0.045% respectively. Such steel accounts for a large proportion of the total output of steel.

This kind of steel can be smelted by oxygen converter, open furnace or electric furnace, and is generally hot-rolled into steel plates, steel strips, profiles and bars. Steel plates are generally delivered in hot rolled (including controlled rolling) or normalized treatment. The chemical composition, tensile properties, impact work and cold bending properties of steel shall comply with the relevant regulations. In China's national standard GB700-88, such steel is divided into 5 grades according to the yield point value, and is divided into 4 grades according to quality. Its brand is composed of four parts in order: the letter Q representing the yield point, the yield point value, the quality grade symbol, and the deoxidation method symbol. This type of steel has a very wide range of applications, most of which are used as welded, riveted or bolted steel structural parts, and a few are used to make various machine parts. Low strength Q195, Q215 steel used in the production of low carbon steel wire, wire mesh, roof panels, welded steel pipes, anchor bolts and rivets. Q235 steel has medium strength, good plasticity and toughness, and is easy to form and weld. This steel is mostly used as steel bars and steel structural parts, but also used as rivets, railway spikes and various mechanical parts, such as bolts, tie rods, connecting rods and so on. The higher strength Q255, Q275 steel is used to make a variety of agricultural machinery, can also be used as steel bars and railway fishboards. According to the special performance requirements of some industrial steel, the composition of ordinary carbon structural steel is slightly adjusted to form a series of professional steel, such as riveted screw steel, bridge steel, pressure vessel steel, hull steel, boiler steel. In addition to strictly controlling chemical composition and ensuring conventional performance, professional steel also provides for some special inspection items, such as low-temperature impact toughness, aging sensitivity, gas, inclusion and fracture in steel.