Metal rolling of different types is commonly used in the construction of buildings. Top-grade steel significantly increases the strength of concrete casts.
Prefabricated facilities made of rolled steel are used as a framework for buildings and supporting structures for various technological facilities. When choosing metal, pay attention to a quality steel plate supplier.
Scope of Application:
Steel is represented in two types of products — profile and rebar. Pipes, square and rectangular sections, channels, and angles are in great demand. Rebar is subdivided into wire, smooth and ribbed fixture, with a diameter of up to 32 mm.
Rebar is used to reinforcing concrete structures, and the profile is used to assemble metal products. The assembly of metal elements is mainly performed by welding, bolted, and riveted joints.
The construction steel requirements are regulated by GOST 27772-88, “Rolled steel for construction steel structures”.The document defines the range of alloys, provides classification, production rules, application, and metal usage.
According to GOST, steels are divided into 2 main types according to their composition:
- carbon steel;
- alloy steel.
The amount of carbon determines the strength of a steel structure. The more carbon is, the stronger the metal is. According to its quality and application, carbon steel is divided into ordinary quality steel, quality structural steel, and tool steel.
Carbon steel of standard quality is an alloy of iron and carbon. The main characteristics of carbon steel are yield strength and tensile strength, and relative elongation value.
- low-alloy steel with less than 0.25% carbon content;
- medium-carbon steels contain 0.25-0.60% carbon;
- high-carbon steel contains more than 0.60% of the content.
Carbon steel St3 is most widely used in construction to manufacturing metal structures of civil and industrial buildings and structures and pipelines.
To increase strength, different metals are added to the iron alloy. This process is called alloying. Alloy steel is specially alloyed with one or more elements that improve its physical and mechanical properties. Alloy steel is divided into high-alloyed, medium-alloyed, and low-alloyed, depending on the alloying elements’ content.
- low-alloyed — up to 2.5% of additional metals;
- medium alloyed — about 2.5-10% additions;
- high-alloyed — more than 10% of impurities.
Alloyed steel is considered to be of higher quality than carbon steel. They are used for making critical structures in construction, space, machine-building, and railroad industries. GOST and structural calculations determine the choice of steel type.
Construction Steel Designations:
Standard grades have the following designations: the letter C (construction steel) in front, followed by three numbers — material yield point, N/mm2, then letters and numbers indicating the variant chemical composition, indication of special heat treatment, or increased corrosion resistance.
The most effective means of reducing the steel intensity and the cost of structures is to increase steel strength. The cross-sectional dimensions of many structural steel elements and their mass depend on the yield strength and the materials’ time resistance.
The main advantage of low-alloy steel compared to St3 steel is its greater strength while maintaining sufficiently high ductility and weldability, allowing you to increase the allowable stresses and reduce metal consumption to manufacture structures with increased resistance to atmospheric corrosion.