Iso 13920 Bf Better Jun 2026

The standard defines :

BF sits in the for most industrial welded fabrications: tighter than structural but not as demanding as machined components.

Each class applies separately to:

A 300 mm tall vertical post welded to a base plate must be perpendicular within ±15 arc-minutes (approx. ±1.3 mm measured at the top).

provides a well-balanced, fine tolerance regime for welded fabrications – tighter than structural norms but achievable with good welding practice. Use BF when you need consistent fit and moderate precision without resorting to post-weld machining. iso 13920 bf

This is a common selection for general mechanical engineering and steel construction where high precision is required but not to the extreme levels of specialized machinery (which might use AE or AF), nor the looser levels of heavy civil construction (which might use CG or CH).

is a specific technical designation used in engineering drawings to define the general tolerances for welded structures. When you see this code, it means the manufacturer must follow the Medium tolerance class for dimensions (B) and a Standard accuracy class for shape and position (F). What is ISO 13920? The standard defines : BF sits in the

ISO 13920 is frequently updated. While the 1996 version was standard for decades, the latest ISO 13920:2023 revision is now the active international benchmark. ISO 13920 - iTeh Standards

When applying ISO 13920 to parts made using the Butt Fusion technique, several considerations are key: provides a well-balanced, fine tolerance regime for welded

In the "B" class, the allowed deviation depends on the length of the part. For example: ±1 mm 30 to 120 mm: ±2 mm 400 to 1,000 mm: ±3 mm 2,000 to 4,000 mm: ±6 mm Tolerance Levels for ISO 13920-F (Shape/Position)

ISO 13920:2015 provides a comprehensive guide for specifying and controlling the dimensions and geometrical tolerances of fabricated and welded products. For the Butt Fusion welding technique, adhering to these guidelines can help ensure that parts are produced to the necessary quality standards, are dimensionally accurate, and function as intended. As manufacturing processes and product specifications evolve, understanding and applying standards like ISO 13920 becomes increasingly important for producing high-quality products consistently.