I-beam, also known as steel beam (English name universal Beam), is a long steel with the section of the I-shaped. I-section steel is divided into hot rolIed I-beam and lightweight I-beam I-beam is mainly divided into ordinary I-beam, light I-beam, low alloy light I-beam . The wing of ordinary I-beam and light I-beam gradually thinner from the root to the side, with a certain Angle. The type of ordinary I -beam and light I-beam is expressed by the Arabic number of its waist height in centimeters. . I-beam is mainly used in building structure, curtain wall engineering, mechanical equipment ,vehicle manufacturing and so on.