... .29mm-508mm. (1/8''-20'')1.2mm-39mm Technique Seamless, welded Usage 1. Low and middle pressure fluid transportation ... -1984seamless steel tbesand pipesfor casingAPI SPEC 5CTJ55, N80APISeamless steel tubes foroil casing andtubing in oil wellsAPE SPEC 5LA, B, ... , 20ASTM A179, ASTM A192 ASTM SA179,SA192, BS3059Seamless Steel Tubes for high pressure --Chemical fertilizer equipmentGB6479-8610, 20G, Q345, ...