En Iso 13920-bf Review

Understanding EN ISO 13920-BF: A Guide to Welding Tolerances

Imagine a team of engineers designing a massive steel frame. They know that when you apply intense heat to metal during welding, it expands, contracts, and twists. Without a shared "tolerance" agreement, the person welding the frame might think a 5mm warp is fine, while the person installing the machinery on top thinks it's a disaster. This is where EN ISO 13920 steps in. It provides a common language for general tolerances for welded constructions Breaking Down the "BF" The suffix en iso 13920-bf

Conclusion

EN ISO 13920 — Overview and key points

tolerance classes

This standard specifies (fine, medium, coarse) for: Understanding EN ISO 13920-BF: A Guide to Welding

• Clarify BF meaning in drawing title block or project WPS
• Attach ISO 2553 weld symbol with backing flag if needed
• Confirm backing type (permanent/removable) in welding specification

Review Note: These values are generally achievable by a competent welder using standard fixtures without post-weld machining. Clarify BF meaning in drawing title block or

• Straightness & Flatness:

  (straightness, flatness, and parallelism). Class F is often used for structural assemblies where moderate precision is required. Summary of Tolerances