American Standard pipe is a hollow cross section, peripheral joints of the steel strip. The steel pipe has a hollow section, as fluid transporting pipeline, American Standard seamless steel tube standards such as oil, natural gas, coal gas, water and some solid materials such as pipelines. Compared withsteel and roundsteelinsolid, flexural torsional strength in the same time, the weight is light, is a kind of economic section steel, widely used in the manufacture of structural parts and mechanical parts, such as the oil pipe, automobile transmission shaft, the bicycle frame and steel construction with scaffold. Manufacturing circular parts with a pipe, which can improve the utilization rate of materials, simplify the manufacturing process, material saving and working hours, such as rolling bearing ring, Jack and so on, has been widely used in steel pipe manufacturing. Steel pipe or all kinds of conventional weapons indispensable materials, gun barrels are made of steel. The shape of steel pipe by cross section can be divided into round tube and special tube. Due to the same condition, the circular area is the largest, and the circular tube can be used to transport more fluid. In addition, the ring cross section in the internal or external radial pressure, the force is more uniform, therefore, the vast majority of steel pipe is round tube.双语对照