⚠️ These values are industry guidelines. For definitive figures, always refer to the official ISO 20457 standard.
General tolerances used when dimensional requirements are not the primary quality focus. Series 2 (Accurate Production):
A key concept within the ISO 20457 PDF is the distinction between two types of dimensions: iso 20457 tolerance table pdf
If you are looking at a PDF of the standard, you will locate the relevant row based on the basic size of the component. You will then cross-reference that row with the column corresponding to the specific feature (e.g., shaft diameter vs. bore diameter). The result is a plus/minus value or a bilateral tolerance that defines the acceptable window of measurement.
The standard, which replaced DIN 16742, defines the tolerances and acceptance conditions for plastic molded parts. It uses Tolerance Groups (TG) to classify accuracy based on material properties and manufacturing processes. Key Tolerance Group: TG6 ⚠️ These values are industry guidelines
Introduced in 2018, (titled "Plastics molded parts — Tolerances and acceptance conditions" ) replaced the older German standard DIN 16742 .
Download ISO 20457 Tolerance Table PDF for Precision Engineering Series 2 (Accurate Production): A key concept within
): Amorphous plastics (like Polycarbonate or ABS) experience low, uniform shrinkage (approx. 0.3% to 0.7%). Semi-crystalline plastics (like Polypropylene or Polyethylene) experience high, anisotropic shrinkage (approx. 1.5% to 3.0%), making them much harder to hold to tight TGs.
ISO 20457 specifies the possible manufacturing tolerances for plastic molded parts. It applies to injection molding, compression molding, transfer molding, and rotational molding of thermoplastic and thermosetting materials. The standard serves three primary functions:
If you are looking for a specific (like TG3 for high precision) or need help calculating shrinkage values for a specific material like ABS or Polycarbonate , let me know!
