2ASystems, Equipment and Components

2A Systems, Equipment and Components

N.B.: For quiet running bearings, see the Munitions List.

2A001 Anti‑friction bearings, bearing systems and components, as follows:

N.B.: SEE ALSO 2A101.

a. Ball bearings and solid roller bearings, having all tolerances specified by the manufacturer in accordance with ISO 492 Tolerance Class 4 or Class 2 (or national equivalents), or better, and having both ‘rings’ and ‘rolling elements’, made from monel or beryllium;

Note: 2A001.a. does not apply to tapered roller bearings.

1.               ‘Ring’ ‑ annular part of a radial rolling bearing incorporating one or more raceways (ISO 5593:1997).
2.               ‘Rolling element’ ‑ ball or roller which rolls between raceways (ISO 5593:1997).

c. Active magnetic bearing systems using any of the following, and specially designed components therefor:

1. Materials with flux densities of 2.0 T or greater and yield strengths greater than 414 MPa;

2. All‑electromagnetic 3D homopolar bias designs for actuators; or

3. High temperature (450 K (177°C) and above) position sensors.

2A101 Radial ball bearings, other than those specified by 2A001, having all tolerances specified in accordance with ISO 492 Tolerance Class 2 (or ANSI/ABMA Std 20 Tolerance Class ABEC–9 or other national equivalents), or better and having all of the following characteristics:

a. An inner ring bore diameter between 12 mm and 50 mm;

b. An outer ring bore diameter between 25 mm and 100 mm; and

c. A width between 10 mm and 20 mm.

2A225 Crucibles made of materials resistant to liquid actinide metals, as follows:

a. Crucibles having both of the following characteristics:

1. A volume of between 150 cm3 (150 ml) and 8,000 cm3 (8 litres); and

2. Made of or coated with any of the following materials, or combination of the following materials, having an overall impurity level of 2% or less by weight:

a. Calcium fluoride (CaF2);

b. Calcium zirconate (metazirconate) (CaZrO3);

c. Cerium sulphide (Ce2S3);

d. Erbium oxide (erbia) (Er2O3);

e. Hafnium oxide (hafnia) (HfO2);

f. Magnesium oxide (MgO);

g. Nitrided niobium‑titanium‑tungsten alloy (approximately 50% Nb, 30% Ti, 20% W);

h. Yttrium oxide (yttria) (Y2O3); or

i. Zirconium oxide (zirconia) (ZrO2);

b. Crucibles having both of the following characteristics:

1. A volume of between 50 cm3 and 2,000 cm3; and