Special sectim pipe are seamless steel pipes made into various special-shaped shapes by cold drawing.  Special-shaped pipes are divided  according to the broken section。 But according to the material, they can also be divided into seamless steel pipes, special-shaped pipes of aluminum alloy, and special-shaped seamless steel pipes are widely used in various structural parts, tools and mechanical parts.  Compared with round pipes, special-shaped pipes generally have larger moments of inertia and section modulus, and have greater bending and torsion resistance, which can greatly reduce structural weight and save steel.