Stainless steel pipe of grade 304,304L,316,316L,321/H,310/S,317/L,347H and etc with its features of resistance to heat, grain boundary corrosion, stress corrosion cracking and weather as well as being highly formable, machinable, and strong with or without being magnetizable were wildly used in industry fields such as pressure equipment, chemical, machinery, construction, vessel building, petrochemical, papermaking, , sewage treatment and etc.