The nominal diameter can be used to calculate the original cross-sectional area of test pieces of circular cross-section which satisfy the tolerances given in table C 2. For all other shapes of test pieces, the original cross-sectional area shall be calculated from measurements of the appropriate dimensions, with an error not exceeding ± 0,5 % on each dimension.
Table C.2 — Tolerances relating to the transverse dimensions of test pieces
Dimensions and tolerances in millimetres
| Designation | Nominal transverse dimension | Machining tolerance on the nominal dimension 1) | Tolerance on shape |
|---|---|---|---|
| Diameter of machined test pieces of circular cross-section | 3 | ± 0,05 | 0,0252) |
| > 3 ≤ 6 | ± 0,06 | 0,032) | |
| > 6 ≤ 10 | ± 0,075 | 0,0362) | |
| > 10 ≤ 18 | ± 0,09 | 0,0432) | |
| > 18 ≤ 30 | ± 0,105 | 0,0522) | |
| Transverse dimensions of test pieces of rectangular cross-section machined on all four sides | Same tolerance as on the diameter of test pieces of circular cross-section | ||
| Transverse dimensions of test pieces of rectangular cross-section machined on only two opposite sides | 3 | 0,143) | |
| > 3 ≤ 6 | 0,183) | ||
| > 6 ≤ 10 | 0,223) | ||
| > 10 ≤ 18 | 0,273) | ||
| > 18 ≤ 30 | 0,333) | ||
| > 30 ≤ 50 | 0,393) | ||
| 1) Tolerances js 12 in accordance with ISO 286-2. These tolerances are applicable if the nominal value of the original cross-sectional area (So) is to be included in the calculation without having to measure it. | ||
| 2) Tolerances IT9 | } | Maximum deviation between the measurements of a specified transverse dimension along the entire parallel length (Lc) of the test piece. |
| 3) Tolerances IT13 | ||