The range of profiles that can be produced by extrusion is almost endless. For this reason, there are no general rules detailing potential solutions and applicable tolerances. Profile design, wall thickness and alloy are some of the crucial factors directly affecting tolerances. In this connection it is important to mention that tighter tolerances can affect productivity and, consequently, price. Some profile manufacturers have standard tolerances of their own. Others use national standards for their productionn. CEN, the European Committee for Standardisation, had prepared European standards. These EN norms will gradually replace the different national standards. In the dialogue between the customer and the supplier it is therefore in each case important to clarify which standard/norm applies. Below you will find extracts from the profile norms EN 755-9 and EN 12020-2.
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