(Such as hot-rolled steel), purlins and other light beams can also be used cold-formed Z-shaped steel and channel (see cold-formed steel). Steel beam processing is simple, the cost is cheaper, but the steel section size by a certain size restrictions. When the load and span larger, the use of steel section can not meet the strength, stiffness or stability requirements, the use of composite beams.
Made of steel or steel welded or riveting. Due to riveting costs, often based on welding. Commonly used welding composite beam is composed of upper and lower flange plate and web composed of cross-section and box section, the latter is more expensive, and the production process more complex, but has a large bending stiffness and torsional stiffness , Suitable for lateral load and torsion requirements are higher or beam height is limited and so on.
A special type of composite beam, by the rolling I-beam by flame cutting and then dislocation welding, welding beam is higher than the original I-beam (increase the hexagonal hole half), thereby enhancing the beam carrying capacity and bending Stiffness; due to the shape of the hexagonal hole on the web, named honeycomb beam.