Nuclear Non-proliferation Import and Export Control Regulations — A.2.4
materials resistant to corrosion by UF 6 , for containing vortex tubes or separation nozzles. A.2.4.5.7 Feed systems/product and tails withdrawal systems Especially designed or prepared process systems or equipment for enrichment plants made of or protected by materials resistant to corrosion by UF 6 , including: (a) feed autoclaves, ovens, or systems used for passing UF 6 to the enrichment process; (b) desublimers (or cold traps) used to remove UF 6 from the enrichment process for subsequent transfer upon heating; (c) solidification or liquefaction stations used to remove UF 6 from the enrichment process by compressing and converting UF 6 to a liquid or solid form; and (d) product or tails stations used for transferring UF 6 into containers. A.2.4.5.8 Header piping systems Especially designed or prepared header piping systems, made of or protected by materials resistant to corrosion by UF 6 , for handling UF 6 within the aerodynamic cascades. This piping network is normally of the double header design with each stage or group of stages connected to each of the headers. A.2.4.5.9 Vacuum systems and pumps (a) especially designed or prepared vacuum systems, including vacuum manifolds, vacuum headers and vacuum pumps, designed for service in UF 6 -bearing atmospheres; and (b) vacuum pumps especially designed or prepared for service in UF 6 -bearing atmospheres and made of or protected by materials resistant to corrosion by UF 6 . These pumps may use fluorocarbon seals and special working fluids. A.2.4.5.10 Special shut-off and control valves Especially designed or prepared bellows-sealed valves, manual or automated, shut-off or control, made of or protected by materials resistant to corrosion by UF 6 and with a diameter of 40 mm or greater, for installation in main and auxiliary systems of aerodynamic enrichment plants. A.2.4.5.11 UF 6 mass spectrometers with ion sources Especially designed or prepared mass spectrometers capable of taking on-line samples from UF 6 gas streams and having all of the following characteristics: (a) the capability of measuring ions of 320 atomic mass units or greater with a resolution of better than 1 part in 320; (b) ion sources constructed of or protected by nickel, nickel-copper alloys with a nickel content of 60% by weight or more, or nickel-chrome alloys; (c) electron bombardment ionization sources; and (d) collector system suitable for isotopic analysis. A.2.4.5.12 UF 6 /carrier gas separation systems Especially designed or prepared process systems for separating UF 6 from carrier gas (hydrogen or helium). A.2.4.6 Especially designed or prepared systems, equipment and components for use in chemical exchange or ion exchange enrichment plants, including: A.2.4.6.1 Liquid-liquid exchange columns (chemical exchange) Countercurrent liquid-liquid exchange columns with mechanical power input, especially designed or prepared for uranium enrichment using the chemical exchange process. For corrosion resistance to concentrated hydrochloric acid solutions, these columns and their internals are generally made of or protected by suitable plastic materials (such as fluorinated hydrocarbon polymers) or glass. The stage residence time of the columns is normally designed to be 30 s or less. A.2.4.6.2 Liquid-liquid centrifugal contactors (chemical exchange) Liquid-liquid centrifugal contactors especially designed or prepared for uranium enrichment using the chemical exchange process. Such contactors use rotation to achieve dispersion of the organic and aqueous streams and then centrifugal force to separate the phases. For corrosion resistance to concentrated hydrochloric acid solutions, the contactors are generally made of or protected by suitable plastic materials (such as fluorinated hydrocarbon polymers) or glass. The stage residence time of the centrifugal contactors is normally designed to be 30 s or less. A.2.4.6.3 Uranium reduction systems and equipment (chemical exchange) (a) especially designed or prepare