ISO 20457 (and its German equivalent DIN 16742) is the definitive global standard for manufacturing tolerances and acceptance conditions of plastic molded parts
A practical summary of the TG6 group values used for injection molding is available through technical resources like OKW Tolerances ISO Official Standard: The full official text and thumbnails for ISO 20457:2018 are available on the ISO Online Browsing Platform Templates & Snippets: iso 20457 tolerance table pdf
when no individual tolerance is specified directly on the drawing. ISO 20457 (and its German equivalent DIN 16742)
It applies specifically to , die castings, and similar processes. Unlike general machining tolerances, moulded parts have unique shrinkage, warpage, and draft angle requirements. What is your typical process capability (Cpk) for
ISO 20457 also provides general geometrical tolerance tables. For example:
One rainy afternoon, a designer named Lila walked into the shop carrying a folded drawing of a new agricultural pump. Her company had outsourced molds for the past decade, but their latest prototype leaked at the coupling because of an overlooked tolerance. She had been told: come here; these folks care about fit. Ana read the drawing, checked the table, and proposed a blend of interference fit on the drive and a running fit on the bearing bore, with a specified surface finish to keep oil film intact. Lila watched as the team translated abstract values into toolpaths, cutters, and test assemblies.
The free search for an **“iso 20457 tolerance table pdf”” will often yield incomplete versions. The complete official PDF contains more than just the tolerance table. It includes: