Alloy pipes have a hollow cross-section and are widely used as pipes for conveying fluids, such as pipes for conveying oil, natural gas, gas, water, mechanical processing, and certain solid materials. Compared with solid steel such as round steel, alloy steel pipe is lighter in weight when the bending and torsional strength is the same. Alloy steel pipe is a kind of economical section steel, which is widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipes, automobile transmission Axles, bicycle racks, and steel scaffolding used in building construction, etc. The use of alloy steel pipes to manufacture ring parts can improve the utilization rate of materials, simplify the manufacturing process, save materials and processing man-hours, such as rolling bearing rings, jack sets, etc., which have been widely used in steel pipes. Alloy steel pipe is also an indispensable material for various conventional weapons. Gun barrels, barrels, etc. must be made of steel pipes. Alloy steel pipes can be divided into round pipes and special-shaped pipes according to the shape of the cross-sectional area. Due to the condition that the circumference is equal, the area of the circle is the largest, and more fluid can be transported with a circular tube. In addition, when the ring section is subjected to internal or external radial pressure, the force is relatively uniform, so most steel pipes are round pipes.

Alloy pipes include large-diameter alloy pipes, thick-walled alloy pipes, high-pressure alloy pipes, alloy flanges, alloy elbows, P91 alloy pipes and seamless steel pipes, and special fertilizer pipes are also very common.

As an important part of steel products, alloy pipes are divided into two categories: seamless steel pipes (round billets) and welded steel pipes (plates, strip billets) due to their different manufacturing processes and the shape of the pipe blanks used.