SIST EN ISO 294-3:2020

Overview

EN ISO 294-3:2020 - Plastics - Injection moulding of test specimens of thermoplastic materials - Part 3: Small plates - specifies the design and use of two two-cavity ISO moulds (type D11 and D12) for producing small plate test specimens (60 mm × 60 mm). The standard defines preferred thicknesses (1 mm for D11, 2 mm for D12), mandatory mould features and measurement provisions (for example, for moulding shrinkage and weld-line studies). This part is intended for laboratories, quality control and R&D that require repeatable, standardized specimens from injection moulding.

Key Topics and Requirements

• Specimen dimensions: plates of 60 × 60 mm; thickness D11 = 1.0 ± 0.1 mm, D12 = 2.0 ± 0.1 mm.
• Mould configuration: two-cavity moulds with one-end gating; sprue diameter on nozzle side ≥ 4 mm.
• Gate and runner geometry:
  • Gate length = 4.0 ± 0.1 mm.
  • Gate height = (75 ± 5) % of cavity height.
  • Runner length = 25–30 mm; runner depth equals plate thickness (h); runner width at gate ≥ (plate width + 6 mm).
• Ejector and surface requirements: ejector pins must be outside the central 50 mm diameter test area; cavity surfaces polished per ISO 294-1 guidance.
• Instrumentation: a flush pressure sensor position in the cavity is specified (mandatory for moulding shrinkage measurement per ISO 294-4).
• Machine requirements: recommended minimum locking force derived from melt pressure (example: for pmax = 80 MPa the calculation gives ~880 kN).
• Weld lines: moulds can accept inserts to create and study weld lines (Annex A).
• Interchangeability: cavity plates and gate inserts designed for interchangeability in line with ISO 294-1.

Applications and Who Uses It

• Material testing laboratories producing standardized thermoplastic specimens for mechanical testing (e.g., impact, puncture, tensile).
• Quality control teams verifying batch-to-batch consistency, moulding shrinkage and dimensional control.
• R&D and formulation scientists evaluating effects of processing, weld lines and orientation on mechanical properties.
• Tooling and process engineers designing ISO-compliant moulds and setting injection parameters to obtain comparable specimens.
• Certification and standards bodies that require harmonized specimen production for inter-lab comparability.

Keywords: EN ISO 294-3:2020, injection moulding, thermoplastic materials, small plates, D11, D12, test specimens, moulding shrinkage, weld lines, ISO mould.

Related Standards

• ISO 294-1:2017 - General principles and multipurpose/bar specimens (moulding & procedure).
• ISO 294-4 - Determination of moulding shrinkage (uses the pressure sensor position specified in 294-3).
• ISO 6603-1 - Puncture impact testing (example test that uses the preferred specimen dimensions).

This standard ensures repeatable production of small-plate specimens for standardized testing and comparative evaluation of thermoplastic materials and processing effects.