classification represents a specific level of precision. In the ISO 20457 system, tolerance grades typically range from TG1 (most precise) TG9 (least precise) Super-Ingenuity Precision Level : TG5 is generally considered a high-precision grade
High stiffness, low friction, and minimal water absorption.
Unlike virgin polymers with fixed properties, recyclates degrade with each loop. TG5’s current framework is static—it grades a single batch. It does not yet offer a “looping index” that predicts how many cycles a given recyclate can survive before falling below a grade threshold. This is a known gap that TG5 is currently addressing in a planned revision. Iso 20457 Tg5
ISO 20457 (which replaced DIN 16742 ) provides a framework for agreeing on dimensional, shape, and position deviations in plastics, which behave differently than metals due to shrinkage and polymer properties.
: Standard Baseline Precision. This is the "default" for technical parts where fit and function are important but not microscopic. classification represents a specific level of precision
: High-precision groups typically reserved for advanced engineering plastics or specialized molding techniques.
: The full technical details for TG5 are contained in ISO 20457:2018 , which specifies the actual numerical tolerance values for different dimension ranges. TG5’s current framework is static—it grades a single
In the context of , "TG5" refers to Tolerance Grade 5 , which is one of the standard accuracy levels used to define manufacturing tolerances for plastic moulded parts. Understanding ISO 20457 TG5
Determine if your (ABS, Nylon, etc.) can realistically hit TG5
Before any steel is cut, mold flow software should be utilized to simulate how the molten plastic will fill the cavity. This analysis helps engineers predict shrinkage, identify potential warpage, and ensure that the part will cool uniformly within the TG5 tolerance range. 3. Geometric Dimensioning and Tolerancing (GD&T)
Require micro-milling, exceptional tooling precision, and highly specialized mold-flow analysis. 2. High-Precision Components (TG4)