En Iso 13920-bf [better] Jun 2026

For welded constructions, the allowed deviation in a linear measurement depends on the nominal size range. For tolerance class , the limits are as follows:

This is the "Medium" class for lengths and angles. It defines the allowable deviation for measurements like the length of a beam or the degree of an angle. en iso 13920-bf

: Dictates the allowable variation for length, width, height, and angle leg measurements. Class B represents the "Medium" or "B-level" accuracy class. It is the most widely specified standard for structural steelwork, general machine building, and medium-duty heavy equipment. For welded constructions, the allowed deviation in a

Class B allows for the natural thermal distortion that occurs during welding without requiring expensive post-weld machining or straightening processes. : Dictates the allowable variation for length, width,

Understanding EN ISO 13920-BF: The Benchmark for Welded Steel Structure Tolerances

simplifies technical drawings by removing the need for hundreds of individual plus or minus