In a large number of industries, square steel pipes are used. The production of this kind of pipes is increasing day by day. With compare to round steel pipes, square steel pipes are little more efficient. The reason is that the square column is more efficient than the solid circular column.

In a traditional space frame, for the bar members, circular hollow section members are used. At the joint section, by welding along a curve surface, the bar members are joined. Therefore, this process takes very long time and seems to be difficult. To make the problem easier, square steel pipes are used. The square steel pipes are used in a special configuration. Both the perpendicular sides of two square steel pipes are respectively aligned in perpendicular and parallel to the plane of the frame bodies. In this case, by butt-welding, the cross points of the bar members are joined along a short weld line

There are mainly three kinds of forming technology of seamless square tube: hot-rolled, cold-drawn and welded. For the cold drawn square tube, the ability of withstanding localized concentrated load is weak, the welding process produced pipe welds are the weak link, do not apply to the construction of high-end residential buildings. Currently, the domestic general uses cold drawn or welded tube production. While the foreign mainly uses hot rolling process, fully able to meet the requirements of high-end buildings. The high-end hot-rolled seamless square tube construction is with good bearing properties, good weldability, low production costs and high production efficiency.

It is understood that the hot-rolled seamless square tube due to structural features of its own, effectively circumvent the connection between the column and beam welding defects and leading to performance degradation, can significantly improve the problem of low efficiency of the traditional low-rise concrete structure, large pollution, waste of resources and other issues; at the same time, the product is with such good performance as the uniform force, high dimensional accuracy, high strength and good impact resistance, can improve the seismic resistance of high-end architecture, will be widely used in steel high-rise buildings, airports and other construction, and has become the main support materials of the construction industry in the future, with great market prospects. At present, this square seamless steel pipe has been put on the market  and is widely used in high-rise buildings.