Zibo stainless steel pipes are in accordance with the international stainless steel marking method.

Zibo Stainless Steel Pipe -- S20200 (AISI, ASTM) The international marking method for stainless steel, used by the American Iron and Steel Institute, is a three-digit system to denote various grades of forgeable stainless steel. Among them:

① Austenitic stainless steel is indicated by numbers from the 200 and 300 series. ② Ferritic and martensitic stainless steels are denoted by numbers from the 400 series. For instance, some common austenitic stainless steels are marked as 201, 202, 304, 316, and 310. ③ Ferritic stainless steel is marked as 430 and 446, while martensitic stainless steel is marked as 410, 420, and 440C. ④ Stainless steel, precipitation-hardened stainless steel, and high-alloy materials with less than 50% iron content are typically identified by patent names or trademarks.