Shaped tubes are made of all kinds of shaped seamless steel tubes by cold drawing. Special-shaped pipe is generally divided according to the broken section, according to the material can be divided into seamless steel tube, aluminum alloy special-shaped pipe, plastic special-shaped pipe.

Steel pipe special pipe can be divided into oval shaped steel tube, triangular shaped steel tube, hexagonal shaped steel tube, the diamond shaped steel tube, octagonal shaped steel tube, semicircle deformed steel circle, not equilateral hexagons five disc shaped steel tube, the plum flower form shaped steel tube, double convex shaped steel tube, double concave shaped steel tube, melon seeds shaped steel tube, the cone shaped steel tube, corrugated shape profiled steel pipe.

Special-shaped pipe, special-shaped square pipe, rectangular pipe, special-shaped welded pipe and spiral welded pipe, specification: 20*20mm-500mm, wall thickness: 0.6mm-20mm, spiral steel pipe. Specification of spiral steel tube, 219mm-2020mm, wall thickness 5mm-20mm. Straight seam specifications are 4 minutes, 6 minutes, 1 inch, 1.2 inch, 1.5 inch, 2 inch, 2.5 inch, 3 inch, 4 inch, 5 inch, 6 inch, 8 inch, 102, 108, 127, 133, 139, 159, 168, 177, 194, 219, 273, 325 and other specifications of the special pipe generally refers to the rectangular steel pipe.

According to the section characteristics, the tubes can be divided into equal-wall tubes, hetero-wall tubes and variable-section tubes.

Isowall shaped tube Isowall shaped pipes are shaped pipes with the same wall thickness and different cross-sectional shapes. According to the shape of the section, it can be divided into two types: general isowall shaped pipes (FIG. 3-14) and isowall shaped pipes with folded bars (FIG. 3-15). Most of these shaped tubes are formed by cold drawing or continuous rolling of welded tubes.