Usage Hangao Tech food grade 304 stainless steel welded pipe mill line specializes in industrial usage, like HVAC pipe fittings, sanitary tubes, water pipes, valve pipe fittings, petrochemical pipes,� chemical industry, medicine industry, wine-making industry, petroleum industry, food industry, automobile industry, paper making industry, air-condition making industry and so on. Products dealed with our tube mill could reach ASTM, DIN, ISO, GB and JIS standard.