Nitrogen trifluoride tube trailers

Nitrogen trifluoride gas is shipped as a compressed gas in steel cylinders and can also be provided by tube trailer. Metals suitable for use in NF3 systems at ambient temperatures are stainless steel, steel, brass, aluminium, copper, and nickel. Corrosion rates of less than 0.0025 mm/a at about 70°C have been measured for these materials [1,2]. However, the corrosion rate increases significantly in the presence of moisture or HF [2]. Fluorinated polymers such as Teflon, Kel-F, and Viton are not attacked by NF3 at ambient [1,2] and elevated temperatures [3]. These materials are recommended for flexible lines and fittings [1]. At elevated temperatures, where the reactivity is similar to that of fluorine, nickel and Monel are recommended as suitable materials for handling NF3 [1]. 

Nitrogen trifluoride is authorized for shipment as a nonflammable compressed gas in cylinders, including DOT/TC approved trailer tubes. Nitrogen trifluoride is normally compressed to 1450 psig (10 000 kPa) in cylinders. 

Nitrogen trifluoride is authorized for bulk highway shipment at high pressure (usually around 1450 psig) or 9997 kPa in tube trailers. These trailers are made up of a number of large tubes, usually constructed to Specification 3A or 3AA, which are manifolded... 

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