There is no weld on the outer surface of seamless steel pipe, which has a hollow section. It is a change from round steel to hollow round bar, and has good compression resistance. The advantages of seamless steel pipe are high pressure resistance, good toughness, long pipe section and few joints. It is widely used. Seamless steel pipe manufacturing ring parts can improve material utilization, simplify manufacturing processes, save materials and processing hours. A large number of pipelines are used to transport fluids, such as oil, natural gas, gas, water and some solid materials. Compared with solid steel such as round steel, steel pipe is lighter when its bending and torsional strength is the same. It is a kind of economic section steel and widely used to manufacture structural parts and mechanical parts.