The exact deviation allowed depends on the nominal size of the component. Larger components are permitted greater absolute deviations than smaller ones. Linear Dimensions (Class B)
The ISO 13920 standard specifies general tolerances for linear and angular dimensions, as well as for shape and position of welded structures. It is designed to ensure functional suitability in manufacturing without requiring excessive precision that could increase costs unnecessarily. Breaking Down "BF" en iso 13920-bf
Tolerance depends on the length of the shorter leg of the angle. The exact deviation allowed depends on the nominal