Overview
ISO 8394-2:2017 specifies a laboratory method to determine the extrudability of sealants independently of their packaging. Part 2 of the series defines the use of a standardized pneumatic apparatus to extrude conditioned sealant under controlled conditions and measure the extrusion mass or volume. The method provides repeatable extrusion-rate results useful for quality control, product comparison and specification.
Key topics and technical requirements
- Principle: fill a standardized cylinder, extrude sealant under defined pressure/time, weigh the extrudate. Results reported as mass/min or converted to volume/min using density.
- Conditioning: test specimen and apparatus conditioned at the test temperature for a minimum of 12 h. Default temperature (23 ± 2) °C; other allowed temperatures (5 ± 2) °C or (35 ± 2) °C or agreement between parties.
- Apparatus: regulated enclosure; pneumatic apparatus with cylinder volumes 250 ml or 400 ml; orifice diameters 2 mm to 10 mm; compressed air up to 700 kPa. Measurement tools: stopwatch (0.1 s) and balance (0.1 g).
- Test procedure:
- Single-component sealants: three extrusion tests, one apparatus per test; extrude for 30 s at (300 ± 10) kPa (default) or agreed pressure.
- Multi-component sealants: perform extrusions at three pot-life times (quarter, middle, third quarter), using three apparatuses at each time (total nine tests) and plot mean extrusion rate vs time to assess viscosity increase.
- Expression of results: E (g/min) = m × 60 / t. Convert to mL/min using density where required.
- Reporting: include reference to ISO 8394-2, lab name/date, sealant identification (chemical family, colour, batch), conditioning temperature, cylinder volume, orifice diameter, extrusion pressure/time, individual and mean results, density (if used), and any deviations from the standard.
Applications and users
- Quality control and acceptance testing by sealant manufacturers, independent testing laboratories, and construction materials QC teams.
- Product development and R&D teams evaluating extrusion behavior for tooling, application methods (manual or pneumatic guns), and workability.
- Specifications writers, architects, and contractors who require objective, comparable extrusion data for procurement and performance criteria.
- Useful where extrudability independent of packaging is critical (e.g., cartridges vs sausages vs bulk).
Related standards
Keywords: ISO 8394-2:2017, extrudability, sealants, standardized apparatus, extrusion rate, sealant testing, building and civil engineering.
Open preview (PDF)Buildings and civil engineering works — Determination of extrudability of sealants — Part 2: Using standardized apparatus