Allowable Dimensional Tolerances

The dimensional tolerances for welded joints are as shown in the table below.

Standard Location	Classification of Standard Dimensions (mm)	Standard Value a
Welded Fabrication Section	30 or less	±0.5
	More than 30 equal to or less than 120	±0.8
	More than 120, equal to or less than 400	±1.2
	More than 400, equal to or less than 1,000	±2.0
	More than 1,000, equal to or less than 2,000	±3.0

*For welded parts, the dimensional tolerances specified in JIS B0405 for general tolerances of metalwork products, Tolerance Grade C, shall apply.
　　However, for reference dimensions of 6 or less, the classification is unified with the classification for dimensions exceeding 6 but not exceeding 30.
*If a painting/coating is specified, the standard value for material conditions is used.

Caution

The dimensional tolerance for welded sections does not apply to dimensions spanning multiple welded sections. (“a“)
Dimensions extending to welded sections across bent sections are also excluded from application. (“b“)

Examples where dimensional tolerances for welded sections apply

Examples where dimensional tolerances for welded sections do not apply

Caution

For dimensional tolerances within components not involving welded sections, refer to the meviy Sheet Metal Manual “Allowable Dimensional Tolerances“.
Components shall be manufactured within the dimensional tolerances listed in the Sheet Metal Manual. After welding, due to the heat-affected zone caused by welding, the dimensional tolerance grades listed in the Sheet Metal Manual and the dimensional tolerance grades for welded products apply. Please refer to the diagram below for details.

Dimensions within component parts

Example where sheet metal dimensional tolerance grades apply without including welded sections

Dimensions within component parts

Example where weld dimensions are included and weld dimensional tolerance grades apply