Iso 20457 Tolerance Table Pdf

Classifies materials based on their shrinkage behavior (e.g., crystalline, amorphous, reinforced).

Plastics behave fundamentally differently from metals during and after manufacturing. Metal parts are typically machined or stamped, meaning their final dimensions are dictated almost entirely by the precision of the cutting tool. Plastic parts are formed by forcing molten resin into a mold cavity under immense pressure. iso 20457 tolerance table pdf

: Cross-reference the category with the nominal dimension of the part to find the specific deviation (in mm). Implementation and Resources Official Standard : Detailed specifications are available directly from the ISO 20457:2018 Publication Page Working Templates : For practical engineering use, Super-Ingenuity Classifies materials based on their shrinkage behavior (e

The standard (formerly DIN 16742) defines the manufacturing tolerances and acceptance conditions for plastic molded parts . It is primarily used to align expectations between designers and manufacturers regarding dimensional accuracy in injection molding and other plastic processes. Key Tolerance Group: TG6 Plastic parts are formed by forcing molten resin

Map your resin profile to the ISO 20457 material data sheets to determine its baseline achievable Tolerance Grade before finalizing your 2D engineering drawings.

The standard helps engineers move away from arbitrary "general tolerances" (like ±0.1mm across the board) and instead use scientifically backed limits based on material properties and manufacturing capabilities. Key Factors Determining Plastic Tolerances

Historically, engineering documentation relied heavily on metal-machining tolerance standards like ISO 2768. However, polymers exhibit drastically different behaviors than metals, including massive thermal expansion, complex anisotropic shrinkage, and moisture absorption.