... +LF+VD test :chemical,UT,physical test.et. Material: Carbon steel & alloy steel. 20SiMnVB/25MnTiBXt/38CrSi OD(max):800mm, length(max): 2000mm ... . And it made by many kinds of material, carbon steel, alloy steel, stainless steel and so on. And the US TEST of all ... material can be to SEP1921 5E/e. 20SiMnVB/25MnTiBXt/38CrSi Forged Steel ...