... Brand: BoAi Technics : Double-side spiral submerged ARC welded Steel grade : Q235, Q345, J55, X65,X70 Connection : Welding OD : ... gas ,coal gas ,coal slurry distribution ; tubing and casing , auto transmission , construction , heating , power, piles and other fields . Remarks : ... process are made under ISO9001:2000 strictly For Steel products enquiry, pls contact Zora, : sales10(at)shinestar ...