Sunday, 1 November 2026
Standing Office 81 (SOVNPA 81) emblem Viet Nam NVietnam National Presiding Agency
on Countering the Proliferation of Weapons of Mass Destruction
Standing Office 81

3.A.9.Bellows-sealed scroll-type compressors and bellows-sealed scroll-type vacuum pumps having all of the following characteristics:

List
NSG – Nuclear-related dual-use equipment, materials, software and related technology (Part 2) – INFCIRC/254/Rev.13/Part 2
a. Capable of an inlet volume flow rate of 50 m³/h or greater;
b. Capable of a pressure ratio of 2:1 or greater; and
c. Having all surfaces that come in contact with the process gas made from any of the following materials:
1. Aluminium or aluminium alloy;
2. Aluminium oxide;
3. Stainless steel;
4. Nickel or nickel alloy;
5. Phosphor bronze; or
6. Fluoropolymers.
Technical Notes: 1. In a scroll compressor or vacuum pump, crescent-shaped pockets of gas
are trapped between one or more pairs of intermeshed spiral vanes, or scrolls, one of which moves while the other remains stationary. The moving scroll orbits the stationary scroll; it does not rotate. As the moving scroll orbits the stationary scroll, the gas pockets diminish in size (i.e., they are compressed) as they move toward the outlet port of the machine.
2. In a bellows-sealed scroll compressor or vacuum pump, the process gas is totally isolated from the lubricated parts of the pump and from the external atmosphere by a metal bellows. One end of the bellows is attached to the moving scroll and the other end is attached to the stationary housing of the pump.
3. Fluoropolymers include, but are not limited to, the following materials:
a. Polytetrafluoroethylene (PTFE),
b. Fluorinated Ethylene Propylene (FEP),
c. Perfluoroalkoxy (PFA),
d. Polychlorotrifluoroethylene (PCTFE); and
e. Vinylidene fluoride-hexafluoropropylene copolymer.