... / API / AWWA / DIN / BS / JIS and etc. 2.Material: Carbon Steel, Alloy Steel Materials:Q235B ... , X42-X70,etc.1) Standards:GB/T3091-2008,GB/T9711.1, API5L etc.2) Sizes ... Application:Structural pipe,liquid transportation,conveyance of oil and gas,petroleum transportation etc.5) Marking:the ... :Structural pipe,liquid transportation,conveyance of oil and gas,petroleum transportation etc.5) Marking:the ...