Overview
ISO 2507-3:1995 defines the specific test conditions for determining the Vicat softening temperature (VST) of thermoplastic pipes and fittings made from ABS (acrylonitrile/butadiene/styrene) and ASA (acrylonitrile/styrene/acrylic ester). It supplements the general Vicat test method given in ISO 2507-1 and includes informative basic specifications for both ABS and ASA materials.
Key topics and technical requirements
- Scope: Applies to ABS and ASA pipes and fittings for VST determination under the ISO 2507 series.
- Reference method: Uses the general Vicat softening temperature method from ISO 2507-1; Part 3 prescribes material- and product-specific adjustments.
- Apparatus: Specifies using a temperature-controlled oven (see clause referencing oven 4.7) in place of a heating bath for the conditioning step.
- Specimen pre-drying: Pre-dry test specimens immediately before conditioning by placing them in a thermostatted oven at 90 °C ± 2 °C for 2 hours, then cool in air at 23 °C ± 2 °C and (50 ± 5) % RH for 15 min ± 1 min.
- Conditioning: After pre-drying, condition specimens in accordance with the conditioning procedure of ISO 2507-1 (article 6).
- Reporting: Test report content follows ISO 2507-1 (article 8) requirements.
- Informative specifications: Annex A (ABS) and Annex B (ASA) give basic VST specification guidance - both indicate a minimum VST of 90 °C under the prescribed test conditions (product standards may set stricter values where required).
Applications and who uses this standard
- Manufacturers of ABS and ASA plastic pipes and fittings use ISO 2507-3 to verify thermal performance and to support product specifications.
- Quality control and testing laboratories apply the specified pre-drying, conditioning and test apparatus requirements to produce repeatable VST results.
- Product standards writers, procurement teams and regulatory bodies reference the standard when defining acceptance criteria or compliance for piping systems exposed to elevated temperatures.
- Useful for stakeholders assessing material selection, performance under heat, or comparing thermoplastic pipe materials (ABS/ASA) for building services, drainage, or industrial piping.
Related standards
- ISO 2507-1 - General method for Vicat softening temperature testing (primary reference).
- ISO 2507-2 - Part 2: test conditions for PVC pipes and fittings (related within the ISO 2507 series).
- Developed by ISO/TC 138 (plastics piping systems) - relevant for wider thermoplastics pipe testing and specifications.
Keywords: ISO 2507-3, Vicat softening temperature, VST, ABS pipes, ASA fittings, thermoplastics pipes test, plastic pipe testing, material specification.
Open preview (PDF)Thermoplastics pipes and fittings — Vicat softening temperature — Part 3: Test conditions for acrylonitrile/butadiene/styrene (ABS) and acrylonitrile/styrene/acrylic ester (ASA) pipes and fittings
