BS 4185-14:1987

This Part of BS 4185 describes a method for the determination of the pilot diameter, d, of a 60° centre hole, type A, B or R as illustrated in Appendices A to C of BS 328-2:1972, covering the range 0.5 mm ⩽ d ⩽ 50 mm.

This method applies only to workpieces satisfying the following conditions:

1. force acting at the centre hole, F_G, ⩽ 180 000 N;
2. cutting force, F_s, ⩽ 110 000 N;
3. where ⩾ 3 or ⩾ 6.3 (see BS 328-1 for D in relation to d) (see also clause 2).

NOTE 1 The theoretical concept is explained in Appendix A and additional considerations are given in Appendix B.

NOTE 2 A typical centre hole is illustrated in Figure 1.

NOTE 3 The titles of the publications referred to in this standard are listed on the inside back cover.

Applies to certain types of centre hole described in BS 328-2. Calculations apply to work pieces which are to be machined on centres providing they satisfy specified conditions.