GB/T3091 Q235 Q345 ERW Welded Steel Tubes Quick Details: Application: Welded steel pipes delivering low pressure liquid such as water,air,heating steam and gasses. size: OD:10.2-2540mm WT:0.5-65mm Length:3-12m Steel Grade: Q195,Q215A,Q215B,Q235A,Q235B,Q295A,Q295B,Q345A,Q345B Processing: Steel pipe shall be processed with anyone of longitudinal-seam high-frequency electrical resistance welding,longitudinal-seam submerged arc welding and spiral-seam submerged arc welding. Mechanical property requirements: Mechanical property requirements of steel pipe shall comply with those specified in the following table,which of other steel grade shall be determined by supply and demand sides through negotiation. Grade Lower yield strength Rel/N/mm² No less than Tensile strength R/N/mm² No less tha…