Technical Standards

5. Flatness

Three specifications are possible:
a) unlevelled
b) roller levelled
c) multiple roller levelled

If not otherwise specified, category b. is supplied.

Flatness tolerances, of roller levelled plates or sheets, with no or small what is classed as small unperforated margin to a maximum length of 2 m:

Width of sheet (mm)		Permissible tolerance of flatness (mm) H
>	<=	<= Dicke	<= 3,00	> 3,00
	1200 mm	10 mm	12 mm	15 mm
1200 mm	1500 mm	14 mm	14 mm	18 mm
1500 mm	2000 mm	15 mm	18 mm	20 mm

Method of measurement:
The sheets are placed on a perfectly flat table. A ruler which does not flatten the material will give the degree of flatness, the measurement being from the highest point of the sheets to the table surface (see picture 6). Special arrangements need to be agreed for sheets with large margins or blank areas.