Toleranssoitu

Toleranssoitu is a Finnish term used in mechanical engineering and manufacturing to describe a part or feature whose size or geometry is controlled by a specified tolerance. A toleranced feature is manufactured to lie within a defined range around a nominal size or shape, ensuring predictable function and interchangeability of parts.

Tolerancing is typically indicated on technical drawings and may be based on standards such as ISO 286 for linear dimensions or ISO 1101 for geometric tolerances. A common presentation uses a nominal dimension with a plus/minus deviation, or a defined tolerance zone. For example, a diameter stated as 20.00 mm with a tolerance of ±0.05 mm requires an actual size between 19.95 and 20.05 mm. Tolerances can also be unilateral, specifying limits on only one side.

In addition to linear dimensions, tolerances apply to other geometries through geometric tolerancing, governing features such as roundness, cylindricity, position, and runout. The combination of tolerances on mating parts (for example, a hole and a shaft) determines the fit, which can be clearance, transition, or interference, affecting assembly and function.

On production drawings, toleranced features are accompanied by notes and references to standards. Verification is performed through metrology and inspection procedures to ensure conformity. If no tolerances are specified, general or default tolerances may apply, potentially increasing variability between batches.

Toleranssoitu parts rely on standardized tolerancing practices to achieve reliable assembly, consistent performance, and interchangeability across manufacturing runs.