... #,20# Materials:Q235 Length:8,9,10 standard:ISO9001:2000 11# I-Beam can be used for mine tram road size ... :9#,11#,12#,20# Materials:Q235Length:8,9,10standard:ISO9001:2000 HeBei ... & QU120, I-beam of the mine usage steel of 9#11# & 12#, U-Beam for the mine support steel of 25U29U ... consumers from now on more than ten years. I-Beam 11#