| Nominal Outside Diameter ($d_n$) (mm) | Tolerance (mm) | | :--- | :--- | | $d_n \le 16$ | +0.3 / 0 | | $16 < d_n \le 63$ | +0.4 / 0 | | $63 < d_n \le 110$ | +0.5 / 0 | | $110 < d_n \le 160$ | +0.6 / 0 | | $160 < d_n \le 225$ | +0.7 / 0 | | ... | ... |
Because ISO 20457 is a classification standard, its tables do not provide the raw numbers for every single dimension (that is the job of ISO 286, ISO 2768, etc.). Instead, it provides a .
like ABS or Polypropylene are categorized under this standard? iso 20457 tolerance table pdf
If you truly need a working reference without paying for the full standard, these sources offer legally compliant extracts:
"We sell trust," Mei said. "We sell parts that keep someone's machine running." Javier nodded; Mr. Owens thumped the bench with a palm. They decided to hold the line. Instead of racing to the bottom on price, they focused on value: traceability, documentation, faster turnaround, and the small but critical assembly testing they insisted on. They printed the tolerance table into their job sheets, used it to teach clients why a tighter fit mattered for longevity, and even offered tolerance-driven design advice to engineers who were used to outsourcing without oversight. | Nominal Outside Diameter ($d_n$) (mm) | Tolerance
The standard ensures that parts are interchangeable and that pumps from different manufacturers (or replacement parts from third parties) will fit and function correctly within the specified limits.
Compare this to ISO 286 for metal (IT7 grade for 100–200 mm: about ±0.035 mm). The plastic tolerance is nearly 10x wider. This illustrates the core lesson of ISO 20457: Instead, it provides a
: High-shrinkage materials (like POM or PA6) typically require larger tolerance values compared to low-shrinkage materials (like ABS or PC). OKW Gehäusesysteme Reference Documents & PDF Guides