Carbon Steel Pipe with High Quality 1.WT:4-70mm OD:25-370mm 2.Certification ... exchanger tube- Pipeline seamless pipe10-530×1.5-36 high-pressure seamless pipe for chemical fertilizer equipment 20,16Mn, ... works, mining, textile, electric power, boilers, drinking water, machinery, military industryDN80-1500-square pipeQ195,Q235,Q345,20#GB/T6278-2002 ... GR.B/A106 GR.B Carbon Steel Pipe with High Quality