ISO DIS 20457

Description / Abstract: This standard specifies possible manufacturing tolerances for plastic moulded parts.

It specifies limits for size dimensions (two-point dimensions) as indirect tolerancing (general tolerances) and proposes limits for direct tolerancing (indication of deviation at nominal size dimension).

This standard is a complementary GPS standard for the process of plastic moulding (see ISO 14638:2015). For more detailed information on the relationship of ISO 20457 to the GPS matrix model, see Annex G.

This standard addresses injection moulding, injection compression moulding, transfer moulding, compression moulding and rotational moulding of non-porous moulded parts made from thermoplastics, thermoplastic elastomers and thermosets of thermoplastics. It is possible to apply this standard to other plastic processes if agreed to by the contractual parties.

Moulded part surface quality deviations such as sink marks, undesired flow structures and roughness as well as joint lines are not addressed in this standard.

This International Standard is not intended to supplant, replace or in any way interfere with requirements for tolerances found in product standards.