Seamless special-shaped steel pipe is made of various special-shaped seamless steel pipe by cold drawing. Seamless special-shaped steel pipes are generally distinguished according to the broken section, and can be divided into seamless special-shaped steel pipes, aluminum alloy seamless special-shaped steel pipes, plastic seamless special-shaped steel pipes according to the material. The development of seamless special-shaped steel pipe is mainly the development of product varieties, including section shape, material and performance. Extrusion method, oblique die rolling method and cold drawing method are effective methods to produce seamless profiled steel pipes. They are suitable for producing seamless profiled steel pipes with various sections and materials. In order to produce a wide variety of seamless special-shaped steel tubes, it is necessary to have a variety of means of production. In the 1990s, on the basis of cold drawing, China developed dozens of production methods, such as roll drawing, extrusion, hydraulic pressure, spinning, spinning, continuous rolling, rotary forging and die-free drawing, and constantly improved and created new equipment and processes. 无缝异型钢管分，异型方管、矩无缝异型钢管、异型焊管、螺旋焊管，规格：20*20mm-500mm，壁厚0.6mm-20mm，螺旋钢管规格，219mm-2020mm，壁厚5mm-20mm.直缝规格有4分、6分、1寸、1.2寸、1.5寸、2寸、2.5寸、3寸、4寸、5寸、6寸、8 寸、102、108、127、133、139、159、168、177、194、219、273、325等规格无缝异型钢管一般多是指方矩型钢管。
Seamless special-shaped steel pipe is divided into four parts, special-shaped square pipe, moment seamless special-shaped steel pipe, special-shaped welded pipe, special-shaped welded pipe, special-welded pipe, spiral welded pipe, specification: 20*20mm-500mm, wall thickness 0.6mm-20mm, spiral steel pipe specification, 219mm-2020mm, 219mm-2020mm, wall thickness 5mm-20mm.Strait specification specification has 4 minutes, 6 minutes, 1 incincinch, 1.2 inch, 1.2 inch, 1 inch, 1.2 inch, 2 inch, 2.5 incincincincinch, 2.5 inch, 2.5 incinch, 2 incincincincinc3 incincincincincincinc, 4 incincincinch, 5 inch, 5 inch, The results of this study are as follows:1. 19, 273, 325 and other specifications of seamless special-shaped steel pipes generally refer to rectangular steel pipes.
Classification of Seamless Special-shaped Steel Pipe
According to the shape and size of steel tube cross section, it can be divided into iso-wall thickness special-shaped seamless steel tube (code D), unequal-wall thickness special-shaped seamless steel tube (code BD), and variable-diameter special-shaped seamless steel tube (code BJ).
Seamless special-shaped steel pipes are generally distinguished according to the broken section, and can be divided into seamless special-shaped steel pipes, aluminum alloy seamless special-shaped steel pipes, plastic seamless special-shaped steel pipes according to the material. The following is mainly about the seamless special-shaped steel pipe.
Seamless special-shaped steel pipe can be divided into elliptical, triangular, hexagonal, rhombic, octagonal, semi-circular, unequal hexagonal, five-petal plum-blossom, double convex, double concave, melon-shaped, conical and corrugated special-shaped steel pipes. Steel pipe.