The use of EN ISO 13920-BF offers several benefits and advantages, including:
For parts where centering is important (e.g., a boss on a plate).
EN ISO 13920-BF is an essential standard for manufacturers and fabricators of welded constructions and parts. By understanding and applying the guidelines and tolerances specified in the standard, manufacturers can ensure that their products meet the required quality and precision standards. The standard promotes consistency, interchangeability, and safety, ultimately contributing to the overall efficiency and reliability of engineering and manufacturing processes. en iso 13920-bf
Angular deviations are calculated based on the of the angle being measured. This metric minimizes layout errors over long spans. Up to 400 mm : Allowed variance of ±plus or minus 45 minutes of a degree ( ±plus or minus 13 mm/m offset). Over 400 mm up to 1,000 mm : Allowed variance of ±plus or minus 30 minutes of a degree ( ±plus or minus 9 mm/m offset). Over 1,000 mm : Allowed variance of ±plus or minus 20 minutes of a degree ( ±plus or minus 6 mm/m offset). Geometrical and Form Tolerances (Class F)
For linear dimensions (length, width, spacing), the deviations are roughly for small dimensions, scaling up based on the nominal size. The use of EN ISO 13920-BF offers several
EN ISO 13920-1:2014 applies to hot-finished structural hollow sections made of non-alloy steel and alloy steel, with or without subsequent heat treatment. The standard is relevant for various types of HSS, including:
: Filtration distributors and cable attachment flanges. Up to 400 mm : Allowed variance of
If your "BF" actually means "B + Filter," you might add:
: Classes range from E (Fine), F (Medium), G (Coarse), to H (Very Coarse).
Larger parts receive broader tolerance bands because thermal distortion compounds over longer spans: Nominal Size Range ( Class B Permissible Deviation ( ±1plus or minus 1 Over 30 to 120 ±1plus or minus 1 Over 120 to 400 ±2plus or minus 2 Over 400 to 1000 ±3plus or minus 3 Over 1000 to 2000 ±4plus or minus 4 Over 2000 to 4000 ±6plus or minus 6 Over 4000 to 8000 ±8plus or minus 8 Over 8000 to 12000 ±10plus or minus 10 Over 12000 to 16000 ±12plus or minus 12 Over 16000 to 20000 ±14plus or minus 14 Over 20000 ±16plus or minus 16 2. Angular Dimensions