(1) Low carbon steel Also known as mild steel, carbon content from 0.10% to 0.30% low carbon steel is easy to accept a variety of processing such as forging, welding and cutting, commonly used in the manufacture of chains, rivets, bolts, shafts and so on. (2) Medium carbon steel Carbon steel with a carbon content of 0.25% to 0.60%. There are a variety of products such as killed steel, semi-killed steel, boiling steel. In addition to carbon, it may contain a small amount of manganese (0.70% to 1.20%).       (3) High carbon steel Often referred to as tool steel, carbon content from 0.60% to 1.70%, can be hardened and tempered. Hammers, crowbars, etc. are made of steel with a carbon content of 0.75%; cutting tools such as drill bits, wire taps, reamers, etc. are made of steel with a carbon content of 0.90% to 1.00%.Hexagonal steel can be composed of various stress members according to the different needs of the structure, and can also be used as the connection between the members. Widely used in a variety of building structures and engineering structures, such as beam, bridge, transmission tower, lifting machinery, ships, industrial furnace, reaction tower, container rack and warehouse shelvesIn the special-shaped pipe is generally according to the section, the overall shape to distinguish, generally can be divided into: Oval shaped steel pipe, triangular shaped steel pipe, hexagonal shaped steel pipe, diamond shaped steel pipe, stainless steel pattern pipe, stainless steel U-shaped steel pipe, D-shaped pipe, stainless steel bend, S-shaped pipe bend, octagonal shaped steel pipe, semi-circular shaped steel circle, Unequal hexagonal shaped steel pipe, five valves plum shaped shaped steel pipe, double convex shaped shaped steel pipe, double concave shaped stainless steel trap pipe, melon shaped shaped steel pipe, conical shaped shaped steel pipe, corrugated shaped shaped steel pipe.