There are four principles for selecting steel structure materials

Steel structure has the characteristics of high strength, light material and good overall stiffness, which is mainly attributed to its material, so we should follow what principles when choosing its material, the following is introduced to the relevant content, let's take a look.

1. Load characteristics

The load of steel structure workshop can be static or dynamic; Acting often, sometimes, or occasionally; Frequently or not often fully loaded, etc. Appropriate steel shall be choosed according to the above characteristics of the load and the necessary quality assurance project requirements shall be provided. Steel with good quality and toughness should be choosed for structural members bearing dynamic load directly. Steel of general quality can be used for structural members subjected to static or indirect dynamic loads.

2. Connection method

Joints may be welded or non-welded. For welded structures, uneven welding and cooling often produce high welding residual stress. The welded structure and welding defects which are difficult to avoid often lead to crack-like damage. The overall continuity and rigidity of the welded structure are good, so that the defects or cracks are easy to spread through each other. In addition, high carbon and sulfur content will seriously affect the weldability of steel. Therefore, the quality requirements of welded structural steel should be higher than that of non-welded structural steel in the same situation, the content of harmful elements such as carbon, sulfur and phosphorus should be lower, and the plasticity and toughness should be better.

Three, the structure of the working environment temperature

The ductility and toughness of steel decrease with temperature, and the toughness decreases sharply at low temperature, especially in the brittle transition temperature zone, which leads to brittle fracture. Therefore, for the steel structure which often or may work at a lower negative temperature, especially for welding structure, the steel with better chemical composition and mechanical properties and brittle transition temperature is lower than the working temperature of the structure should be choosed.

Four, steel thickness

The strength, impact toughness and welding performance of steel with large thickness are poor because of the small compression ratio. And easy to produce three - way residual stress. Therefore, high quality steel should be used in welded structures with large thickness.

We should follow the above four principles when choosing steel structure materials, so we should pay attention to the selection, and then ensure its quality.