Overview
EN ISO 3167:2014 - Plastics: Multipurpose test specimens (ISO 3167:2014) defines requirements for multipurpose test specimens used with plastic moulding materials processed by injection moulding or direct compression moulding. The standard specifies preferred specimen geometries (notably type A and type B tensile specimens), dimensions, preparation, machining, marking and reporting so that a single moulding can yield specimens suitable for a range of mechanical tests. Using multipurpose specimens improves comparability of measured properties by ensuring specimens are in the same processed state.
Key topics and technical requirements
- Specimen types and dimensions: Preferred multipurpose specimens are Type A and Type B tensile forms; Type A includes a narrow parallel-sided portion of 80 ± 2 mm for conversion to other test pieces. Typical dimensions (width, thickness, radii and overall length) and tolerances are specified to control stress concentrations and test reproducibility.
- Preparation methods: Specimens must be prepared by injection moulding, compression moulding, or machining from moulded plates in accordance with relevant normative references. Surfaces must be free from visible flaws and flash must be removed without damaging moulded surfaces.
- Machining rules: Machining of narrower specimens must preserve the moulded central portion; machined widths must not be less than the central portion and must avoid surface damage. Specific guidance is given for cutting ISO bars from the central zone.
- Identification and asymmetry: Broad faces should be marked to indicate cavity/fixed plate side or any asymmetry from moulding, since asymmetry (e.g., thickness variation) can affect flexural and thermal-deflection results.
- Reporting requirements: Test reports shall document specimen type, material identification (grade, manufacturer), moulding/machining methods and conditions, number of specimens, conditioning atmosphere and preparation date.
Practical applications and users
- Who uses it: Materials engineers, quality-control laboratories, plastics test labs, mould/tooling designers, product manufacturers and standards bodies.
- Why use it:
- Obtain coherent, comparable mechanical property data from specimens produced under identical moulding conditions.
- Reduce tooling needs - one mould yields specimens for tensile, flexural, impact and other tests.
- Provide traceable specimen preparation records for certification, R&D and material acceptance testing.
Related standards
Keywords: EN ISO 3167:2014, ISO 3167:2014, plastics multipurpose test specimens, injection moulding, compression moulding, tensile specimen dimensions, specimen preparation, plastics testing.
