Heavy Steel
1. The lifting weight of the factory yard crane: ≥ 25 tons.
2. Steel consumption per square meter: ≥ 50KG/M2. For example, petrochemical factory facilities, power plant buildings, large-span sports venues, exhibition centers, high-rise or super high-rise steel structures.
Light steel
Steel structure light steel is also a relatively vague term, which can generally be understood in two ways. One is the current "Code for Design of Steel Structures" (GBJ 17-88), Chapter 11 "Light steel structures with round steel and small angle steel", which refers to the use of round steel and less than L45 × 4 and L56 × thirty-six × The lightweight steel structure made of angle steel of 4 is mainly used for small structures that are not suitable for manufacturing reinforced concrete structures in the era of steel shortage. It is now largely not adopted, so the revision of the steel structure design code has basically tended to remove it. Another type is the single-layer solid web portal frame structure with light roof and light exterior walls (or masonry exterior walls can be used conditionally) specified in the "Technical Specification for Steel Structures of Light Buildings with Portal Frames". The light weight here mainly refers to the use of lightweight materials for the enclosure. Since the former type is about to be cancelled, the current meaning of light steel mainly refers to the latter type.
In addition, there are also some reference values, such as cost per square meter, maximum component weight, maximum span, structural form, and eaves height, which can provide empirical data when determining whether the factory building is made of heavy steel or light steel. Of course, many buildings now have both light and heavy steel. There is no mention of heavy steel in national regulations or technical documents. In order to distinguish light steel structures in buildings, it may be more appropriate to refer to general steel structures as "ordinary steel". Because the scope of ordinary steel structures is very wide, it can include various steel structures, regardless of the size of the load, and even many aspects of lightweight steel structures. The technical specifications for lightweight building steel structures only specify more specific content based on their "light" characteristics, and the scope is limited to single-story portal frames. From this, it can be seen that the difference between light steel and heavy steel is not in the weight of the structure itself, but in the weight of the accepted enclosure materials, but in the concept of structural design, they are still common
The "Code for Design of Steel Structures" GBJ17-88 has been abolished since December 1, 2003, and the current implementation is the "Code for Design of Steel Structures" GB50017-2003
Equipment steel
Equipment steel structure refers to the steel structure part of large equipment. Based on the experience of technical personnel from Qingdao Metallurgical Engineering (QYETC), the following structures can be classified as equipment steel structure: tower steel structure of bridge girder erection machine, lifting beam of crane, crane body, large equipment support, etc., and are classified as one of the precision steel structures with high requirements for precision, material, connection, etc. For complete equipment, it is the main load-bearing part and plays a structural role in functionality.