SX20 is a modified version of SX10. The pre-punching instead of post-punching, and the pre shear function is added. A cost-effective model. CZ steel is mainly used to build steel structures. In addition to purlins, it can also be used as steel structure supports, beams, and bracing. This also leads to the term steel structure. When it comes to steel structure, first of all, it belongs to a kind of building structure. Building structure refers to a space force system in buildings (including structures) that is made of building materials to bear various loads or functions to act as a skeleton. Building structure can be divided into concrete structure, masonry structure, steel structure, light steel structure, wood structure and composite structure due to different building materials. Among them, steel structure is a structure mainly made of steel, and CZ steel is one of the more common structural forms in modern construction engineering. Why is it more common now? This starts with the characteristics of steel structure: the characteristics of steel structure are mainly reflected in the material, that is, steel. The characteristics of steel are high strength, light weight, and high rigidity, so it is especially suitable for building large-span, super-high and super-heavy buildings; the material has good homogeneity and isotropy, which is an ideal elastic body and conforms to general engineering mechanics The basic assumption of the steel structure; the material has good plasticity and toughness, can have large deformation, and can withstand dynamic loads well; its industrialization degree is high, and the production speed is fast. Through the characteristics just now, the steel structure has: strong stability and strength High, light weight, fast construction speed, good seismic performance, easy installation and control of various shapes, reasonable price, strong economy and practicality. Therefore, the general working workshops and production workshops are mostly steel structures.