... ,Asia,America. product name hot expanded seamless steel pipecertificationAPI5L/5CT certificate,CQM ISO9001:2000 approved.standardGB Series,DIN,EN,ASTM A106/A53.API5L/5CT ... ,JISG AND SO ON.OD21.3-600MMWT6-50MMmaterial20#,45#,16Mn,10#,and low alloy steel OEM ... cracking,chemical fertilizer equipment,drawing-oil-equipment and structure purpose! hot expanded seamless steel pipe