En Iso 13920-bf _top_ File

Designing foundations for pumps or blowers. Transport: Fabricating chassis or frames for vehicles.

In the context of EN ISO 13920, is not a tolerance class from the standard itself. Instead, it appears in welding symbols or technical notes to denote a specific weld preparation shape – typically Backing run with Flat face or Backing + Flat . en iso 13920-bf

In the world of structural steel engineering and fabrication, precision is everything. However, absolute perfection is impossible to achieve in welding due to thermal distortion, material inconsistencies, and human factors. This is where tolerance standards come into play. Designing foundations for pumps or blowers

This is critical for base plates and mounting surfaces. Instead, it appears in welding symbols or technical

If that same beam has a flatness requirement:

This standard is widely used in machine construction , steel structures , rail vehicles, and shipbuilding. Tolerance Tables Overview