... 4) SIMENS PLC Controller 1, Product Name: Nitrogen Machine/ N2 Gas EquipmentA full installation requires air compressor, ... Food packing, Food storing, Electric & Electronic industry, Petro-gas & Oil field, Chemicals & Petro-chemicals, Coal-mine, Metallurgy, Pharmacy, ... blowing, etc. Used in fields such as metal heating treatment, powder metallurgy, magnetic material, copper process, metallic mesh, ...