Square and rectangular tube specifications and manufacturing processes  Square rectangular tubes are one of the most produced types of cold-formed steel, widely used in various industrial sectors. Their forming processes are categorized into direct shaping and round-to-square transformations. The direct shaping process has been extensively promoted and applied in our country, with continuous advancements in technology and equipment levels. It has gone through several stages, including technology introduction, digestion and absorption, and technological innovation. It has evolved from complete reliance on imports in the early stages to now large-scale exports. This article introduces the forming process, key technologies, and the development trend of new technologies for square rectangular tubes.

 Square rectangular tube is a widely used closed steel section.,Compared to a circular tube with the same cross-sectional area, It boasts high strength, large bending section modulus, ease of assembly, and stability and aesthetics., Widely usedConstruction machinery,Automotive, subway, shipbuilding, and other industries. Particularly in the construction sector., Large-size rectangular steel tubes have become the main load-bearing components in steel structure construction.

Rectangular tubes, typically rectangular in shape.Cold Bending Forming（）No Chinese content provided.Rolled continuous molding method production. Due toCold bending formingThe method boasts high production efficiency, enabling uninterrupted production on the pipe welding line, with high yield rate and minimal head loss, widely applied in large-scale production.

Square rectangular tubes can be categorized according to different forming processes, such as directMolding, commonly referred to as "molding.""Direct Square Formation" and "Circular to Square Transformation" (first forming circular tubes and then transforming into square rectangular tubes)Two types. Regarding the characteristics of these two processes, many documents provide comparisons.[1][2]Manufacturers have also adopted different approaches based on the condition of their equipment.Different processes

Welded round and rectangular tube design methods are extensively covered in numerous books and literature. Here, we mainly compare the commonly used methods in roller-type continuous forming.

 (1) "Round-to-Square" Technology

The steel strip is shaped and welded into round tubes using a welding tube mill., Further shaped into square tubes through a sizing machine. Utilizing the "circle to square" process., Utilize round tube forming equipment to first form...No Chinese content provided.To weld round tubes and then convert them into rectangular tubes at the sizing section. For the existing round tube welding production line, it requires minimal investment and is easy to implement.Process relativelyDirect SquareWell-controlled.

(2) Direct Square Process

Direct bending of steel strip into rectangular billets,Then, proceed with welding and shaping.No Chinese content provided. Please provide the text to be translated.Craftsmanship.