In construction, "close enough" is rarely acceptable. The standard defines the allowable deviations in:
While standards like (General Structural Steel) or JIS G 3106 (Rolled Steel for Welded Structures) dictate the chemical composition and mechanical properties (tensile strength, yield point), JIS G 3193 dictates the physical geometry.
JIS G 3193 is a Japanese Industrial Standard (JIS) that specifies the technical requirements for "Hot Rolled Carbon Steel Plates, Sheets and Coils". Here's a brief overview: jis g 3193 pdf
JIS G 3193: Dimensions, Tolerances, and Mass of Steel Plates, Sheets, Strips, and Flats Purpose: Specifies standard sizes, thickness tolerances, and mass calculation methods for hot-rolled/cold-rolled flat steel products.
The standard does not apply to flat bars, and its application is ultimately defined in the relevant product-specific standards that reference JIS G 3193. In construction, "close enough" is rarely acceptable
Some universities with Japanese engineering programs have site licenses for JIS standards. Check your institution's library portal. However, distributing single PDFs outside the network is prohibited.
For example, a standard 10mm plate will have a specific plus/minus tolerance (e.g., ±0.3mm to ±0.8mm) depending on whether the plate width is under 1,600mm or over 2,000mm. B. Width Tolerances Here's a brief overview: JIS G 3193: Dimensions,
Tolerances widen slightly, typically ranging around ±0.45 mm to ±0.70 mm.
This means the deviation from a perfectly flat surface must be 8mm or less for the product to comply with JIS G 3193.
Thickness deviation is the most tightly regulated aspect of JIS G 3193. The allowable variance increases as the nominal thickness and width of the plate increase.