... -2000Fertilizer Equipment-pipeline25-426×6-40 Marine tube 410GB/T5312-1999specificial pressure pipe for vessel manufacturing- tube for boilers and overheating14-426*1.5 ... , boilers, drinking water, machinery, military industryDN80-1500-square pipeQ195,Q235,Q345,20#GB/T6278-2002 Structure, decoration, construction20*20- steel tube for construction