... -1999 3 best quality Supply 10#, 20#, 35#, 45#, 16Mn,Q345B structure pipe GB/T8162-1999 Commodity nameMain ... materialUsageExecutive standardSpecification scopeStructure pipe10#,20#,35#,45#,16Mn,Q345B etcGeneral structure fabricationGB/T8162-1999 Φ 6- ... 12-15-18-20-25273×30-35-38-40-45-50299×8-12-16-20-24-28299×30- ... 8-12-15-20-24-28377×30-37-40-45-50402×10-15-20-25-30-35406×10-20 ...