... steel hollow pipe 1) Standard:API 5L,ASTM 36.10M,A106,A53,DIN 1629,1626,BS,JIS.etc mild steel hollow pipe1) Standard:API ... 5L,ASTM 36.10M,A106,A53,DIN 1629,1626,BS,JIS.etc2) Material: ASTM A106/A53,ST37,35, API ... XXS etc.6) Technique:Hot Rolled,Cold Drawn,Seamless,ERW,LSAW,SSAW,7) Surface treatment:bare,black ... ,boiler,construction,,metallurgy,etc mild steel hollow pipe