321 stainless steel pipe has good processing and welding properties, making cutting, bending, welding and other processing operations easy to perform. Besides, it has superior mechanical properties such as tensile strength, flexural strength and elongation, and can meet the requirements of use in various environments. Because 321 stainless steel pipes have excellent corrosion resistance and high temperature performance, they are commonly seen in petroleum, chemical industry, aviation, aerospace. Since the production process of petroleum and chemical industries involves a large amount of corrosive media such as acids, alkalis, and salts, 321 stainless steel pipes can effectively cope with the corrosion of these media and ensure the stable operation of the equipment. 321 stainless steel pipe has become one of the important structural materials in the aviation and aerospace fields.