The beam specially used for loading the crane inside the plant is called crane beam. Most modern crane beams are in the form of steel structure. According to the load surface of crane beam, they can be divided into section steel beam, combined I-beam, box beam and strut crane beam. H-beam and I-beam are most used. The crane beam is the subgrade supporting the operation of the truss truck, which is mostly used in the steel structure plant. The crane beam is on the track, and the truss truck runs back and forth on the crane beam through the track. The crane beam is similar to the steel beam, but the difference is that the web of the crane beam is welded with dense stiffeners to provide support for the truss truck to lift heavy objects.
When the span and lifting capacity of the crane beam are small and no other measures are required to ensure the lateral stability of the crane beam, the crane beam can not be strengthened or the upper flange can be strengthened with steel plate and section steel. When the span width of the crane beam is large and the lifting capacity is large, the brake structure (brake beam or brake truss) shall be set. The upper flange of the crane beam is the inner flange of the brake beam, The channel steel is the outer flange of the brake beam. The width of the brake beam should not be less than 1.0m. When the width is large, the brake truss should be used. The brake truss is a parallel chord truss composed of angle steel. As long as the stability of the crane beam is firm, an inspection channel can be added. The working level of steel structure crane beam is divided into light level, medium level, heavy level and extra heavy level. Generally, the light level working system is equivalent to A1 ~ A3 level, the medium level working system is equivalent to A4 and A5 level, the heavy level working system is equivalent to A6 ~ A7 level, and the extra heavy level is equivalent to A8 level. The structure of steel structure crane beam system is usually composed of crane beam (or crane truss), braking structure It is composed of auxiliary truss and support (horizontal support and vertical support).