Flatness tolerance for copper sheets and strips – EN 13599
- lateral curvature (c)
The EN 13599 standard explicitly specifies lateral curvature as a limit of deviation from flatness, but it does not define a general overall flatness tolerance for the sheet surface in the same detailed manner as some other industrial standards (e.g., those for aluminium).
Lateral curvature (c): this is the main limitation describing how “straight” the material must be.
Measurement is carried out over a length of 1000 mm, and the curvature value (c) must not exceed the limits listed below.
1 – measured length, 2 – strip width, c – lateral curvature
Dimensions in millimetres
Specified width | Maximum lateral curvature c for specified thicknesses | |||||
|---|---|---|---|---|---|---|
| over | up to and including | up to 0.5 mm inclusive | over 0.5 up to 1.2 mm inclusive | over 1.2 up to 2.5 mm inclusive | over 2.5 up to 3.2 mm inclusive | over 3.2 up to 5.0 mm inclusive |
| 10a | 15 | 7 | 10 | — | — | — |
| 15 | 30 | 4 | 6 | 8 | — | — |
| 30 | 50 | 3 | 4 | 6 | 7 | by agreement |
| 50 | 1250 | 2 | 3 | 4 | 5 | |
| a Inclusive 10. | ||||||