Stainless steel pipe is an important product of iron and steel industry, divided into seamless pipe and welded pipe, plain carbon steel, alloy steel, bearing steel, such as variety, resistant to weak corrosive medium such as air, steam, water and acid, alkali, salt and other chemical etching medium corrosion, in the life is widely used in petroleum, chemical, medical, food, light industry, machinery, instrument, such as industrial pipeline and mechanical structure parts, etc.