Inspectors should:
Angular tolerances apply to angles between welded parts, bevel angles, or non-right-angle joints.
These include flatness, straightness, circularity, concentricity, and others. The tolerance values are often given based on the length of the dimension.
is the international standard titled "Welding — General tolerances for welded constructions — Dimensions for lengths and angles — Shape and position."
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.
The scope of ISO 13920:2015 covers the general tolerances for linear and angular dimensions, and for form and position, for fabricated or machined parts. This includes parts made by various processes such as welding, cutting, and forming. The standard is designed to be applied in the context of specifications for a product or for a type of product. It does not apply to the possible imperfections of the welded joint itself.
In ISO 13920, tolerance classes consist of two letters. The combination breaks down as follows:
In welding fabrication, achieving perfect dimensions is often impractical and cost-prohibitive. is the international standard that specifies general tolerances for linear and angular dimensions, as well as for straightness and flatness, of welded structures.
The standard categorizes general tolerances into several types: