Stainless steel pipe is a kind of hollow long round steel, which is mainly used in industrial transportation pipelines and mechanical structural components such as petroleum, chemical industry, medical treatment, food, light industry, mechanical instrument and so on. In addition, when the bending and torsional strength are the same, the weight is lighter, so it is also widely used in the manufacture of mechanical parts and engineering structures. It is also commonly used as furniture and kitchenware.