1964_IMPORT_AND_EXPORT_(STRATEGIC_COMMODITIES)_REGULATIONS — Page 16

G 16

CAP. 60]

Import and Export (Strategic Commodities) Regulations

[1988 Ed.

[Subsidiary]

Explanatory Notes:

1. For "digital computers" either "incorporated" in or "associated" with, but not "embedded" in, controllers, see Item IL 1565.

Technology for the design and production (except assembly and testing) of two-axis numerical control units with an "embedded" computer remains embargoed.

(b) Machine-tools and dimensional-inspection machines which, according to the manufacturer's technical specifications, can be equipped with numerical control units covered by sub-item (a) above, except:

(i) Boring mills, milling machines, and machining centres having all of the following characteristics:

(1) (a) Not more than three axes capable of simultaneously coordinated contouring motion, i.e. the total number of linear plus rotary contouring axes cannot exceed three. (A secondary parallel contouring axis, e.g. W axis on horizontal boring mills, is not counted in the total of three contouring axes. A secondary rotary table, the centreline of which is parallel to the primary rotary table, is also not counted in the total of three contouring axes. Machines may have non-contouring parallel or non-contouring, non-parallel rotary axes in addition to the three axes capable of simultaneously coordinated contouring motion. Machines having the capability of being simultaneously coordinated in more than three axes are not excluded from embargo even if the numerical control unit attached to the machine limits it to three simultaneously coordinated contouring axes. For example, a machine with a control unit switchable between any three out of four contouring axes is not excluded from embargo); or

(b) Not more than three linear axes plus one rotary axis, but no tilting axis, capable of simultaneously coordinated contouring motion, i.e. the total number of linear plus rotary contouring axes cannot exceed four. (A secondary parallel contouring axis, e.g. W axis on horizontal boring mills, is not counted as an additional contouring axis. A secondary rotary table, the centreline of which is parallel to the primary rotary table, is also not counted as an additional contouring axis. Machines may have non-contouring parallel or non-contouring, non-parallel rotary axes in addition to the four axes capable of simultaneously coordinated contouring motion. Machines having the capability of being simultaneously coordinated in more than four axes are not excluded from embargo even if the numerical control unit attached to the machine limits it to three simultaneously coordinated contouring axes. For example, a machine with a control unit switchable between any three out of five contouring axes is not excluded from embargo);

(2) Maximum slide travel in any axis equal to or less than 3 000 mm;

(3) Spindle drive motor power equal to or less than 35 kW;

(4) Single working spindle (the machine may have multiple tool heads or turrets as standard or optional, but only one working spindle may be operative at a time). A spindle capable of driving a multiple drill head is considered as a single spindle;

(5) Axial and radial motion measured at the spindle axis in one revolution of the spindle equal to or greater than D × 2 × 10-5 mm TIR (peak-to-peak) where D is the spindle diameter in mm;

(6) An incremental positioning accuracy equal to or greater (coarser) than 0.002 mm in any 200 mm of travel;

(7) Overall positioning accuracy in any axis equal to or greater (coarser) than:

(a) ±0.01 mm for machines with total length of axis travel equal to or less than 300 mm;

(b) (0.01+0.0025/300 × (L-300)) mm for machines with a total length of axis travel, L, greater than 300 mm and equal to or less than 3 300 mm;

(c) +0.035 mm for machines with a total length of axis travel greater than 3 300 mm.