Seamless steel pipes have hollow sections and are widely used as pipelines for transporting fluids, such as pipelines for transporting oil, natural gas, water and certain solid materials.
Seamless steel pipes have hollow sections and are widely used as pipelines for transporting fluids, such as pipelines for transporting oil, natural gas, water and certain solid materials. Compared with solid steel such as round steel, steel pipes are lighter in weight with the same bending and torsional strength. It is an economical section steel that is widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipes, automobile transmission shafts, bicycles, etc. Steel scaffolding and other construction steel scaffolding are used to manufacture ring-shaped parts with steel pipes, which can improve material utilization, simplify the manufacturing process, and save materials and processing man-hours.
For example, rolling bearing rings, jack sets, etc. have been widely manufactured from steel pipes. Steel pipes are also an indispensable material for various conventional weapons, and gun barrels are made of steel pipes. According to different cross-sectional areas, steel pipes can be divided into round pipes and special-shaped pipes. Since the circular area is the largest under equal circumference conditions, circular tubes can transport more fluid. Additionally, when the annular portion is subjected to internal or external radial pressure, the force is relatively uniform. Therefore, most steel pipes are round pipes.
However, round tubes also have certain limitations. For example, round tubes are not as strong as square and rectangular tubes under plane bending conditions. Some agricultural machinery frames, steel and wooden furniture, etc. usually use square and rectangular pipes. Special-shaped steel pipes with other cross-sectional shapes are required according to different purposes.
Seamless steel pipes are made from a single piece of metal material with no seams on the surface. According to the manufacturing method, seamless steel pipes are divided into hot-rolled pipes, cold-rolled pipes, cold-drawn pipes, extruded pipes and drawn-tube structures. According to the cross-section, seamless steel pipes are divided into two types: ring and special-shaped. Special-shaped tubes are square, oval, triangular, hexagonal, sunflower seed, star and fin tubes. The larger diameter is 650mm and the smallest diameter is 0.3mm.
Depending on the main purpose, there are thick-walled steel pipes and thin-walled steel pipes. Seamless steel pipes are mainly used as crude oil geological exploration pipes, cracking pipes for petrochemical equipment, boiler pipes, rolling bearing pipes and their trolleys, high-precision structural steel pipes for large tractors and airlines.
