Light Weight Tube Section Mild Tubes S235 S355 Mild Steel Square Pipe Q235 Ms Square Hollow Section Rectangular and Square Black Carbon Steel Pipe . FOB Price US $ 500-860 / Ton. China Seamless Steel Pipe Q345b, Seamless Steel Pipe Humans use natural resources for everything they do. The Seamless Steel Pipe Q345b and China Pipe , Steel Tube , Carbon Steel Pipe products are usually used to get more enegy for specific effects. For example, soil and water can grow food, wood can be burned to provide heat or to build shelters.