I-beams are used in almost every modern construction site, both industrial and civil. With a relatively low specific gravity, they have a high load capacity for deflection, which allows you to effectively distribute the load on the supporting structures. These metal products are manufactured by rolling (shaped steel, hot-rolled I-beam) or by welding. In cross section, they are an H-shaped structure of a wall and two shelves perpendicular to it. Shelves can be internally sloped for additional reinforcement. Such products are suitable for reinforcement with reinforcement of mine shafts (Series C with a slope of 16%) and for the installation of overhead tracks (Series M with a slope of 12%).
Rolled I-beam is also called I-beam. The main areas of application of these metal products are building floors, bridge structures, overhead tracks, supports and columns. Depending on the purpose of the structures being erected, the I-beam steel can be selected for different workloads. Structurally, I-beams differ in thicknesswalls and shelves, the location of the edges of the shelves (their inner edges can be parallel or have a slope). When choosing, the manufacturing method, purpose and technical parameters also matter.
I-beam steel can be produced in compliance with the requirements of state standards (GOST 8239 - 89, GOST 19425 - 74, GOST 26020 - 83 and others), as well as in accordance with the specifications of the manufacturer. The material in the case of rolling are structural carbon steels of ordinary quality. Such a metal structure as a welded I-beam is made from low-alloy structural steel for welded structures.
There are several types of I-beams with parallel flange faces: normal (B), columnar (K), wide-shelf (W), normal (DB), additional series (D and LSH). An I-beam manufactured in accordance with the norms, depending on the purpose, has a length of 4 to 12 m (up to 24 m upon agreement with customers). Can be high (A) or normal (B) rolling accuracy.
Welded steel I-beams are made from sheet metal in several stages. First, blanks of the required dimensions are formed by cutting them from metal, then the edges are milled. The prepared strips are transferred by a crane to the conveyor, crimped and scalded by an automatic installation. Further, the product is rolled on a special mill to remove possible defects and processed on a shot-blasting plant to remove contaminants. The quality of the welded I-beam must comply with the requirements of GOST 23118-99 and GOST 26020-83 (or its parameters are negotiated with the customer in advance).
I-beams make it possible to lighten load-bearing structures by 30% in comparison with hot-rolled supports. Pre-sizing the beams significantly reduces the amount of waste. The disadvantages of I-beams include vulnerability to corrosion if there is no protective coating, as well as the need for specialized equipment, without which they cannot be mounted.
