: Inhomogeneous cooling rates between thick and thin walls introduce internal stresses, warping, and sink marks.
The selection of TG5 is typically driven by the material choice and the part geometry. din 16742 - tg5
Used for coarse or large parts where tight fits aren't critical (e.g., heavy industrial covers). Why Choose TG5? : Inhomogeneous cooling rates between thick and thin
Dimensions determined by a single part of the mold tool. These are typically more accurate. Why Choose TG5
In this standard, stands for Tolerance Group . The standard defines nine groups (TG1 through TG9), where lower numbers represent tighter, more expensive precision, and higher numbers represent looser, more economical tolerances.
In the context of the standard’s tables, TG5 specifies a permissible deviation that is significantly tighter than what might be acceptable for a disposable item, yet achievable without exotic tooling or specialized environment controls. For example, on a nominal dimension of 100mm, the tolerance range in TG5 would be narrow enough to ensure good fitment with mating parts, but wide enough to account for the natural variability of the injection molding process.
DIN 16742 replaced the older DIN 16901 standard in 2013. It establishes standard tolerances for symmetrical and asymmetrical plastic molded parts. The framework accounts for the variable factors inherent to plastic production, such as tool accuracy, processing conditions, and material properties.