Overview
ISO 11127-3:2020 defines a standardized laboratory method for the determination of apparent density of non-metallic blast-cleaning abrasives. This part of the ISO 11127 series uses the pycnometer (Gay-Lussac type) method and is intended to support consistent sampling, testing and specification of abrasives used to prepare steel substrates before painting.
The method ensures repeatable, comparable apparent density data that feed into material selection, dosing and quality-control protocols for blast-cleaning operations.
Key Topics
- Scope: Measurement of apparent density of non-metallic blast-cleaning abrasives as part of the ISO 11127 series. Relates to abrasive types and requirements in the ISO 11126 series.
- Principle: Use of a 50 ml pycnometer and water to determine the mass of a given volume of dried abrasive; calculation uses mass differences and the density of water at the test temperature.
- Reagent and apparatus:
- Distilled or deionized water (ISO 3696 grade 3 or better).
- Pycnometer (Gay-Lussac type, 50 ml with capillary stopper).
- Oven (110 ± 5 °C), balance (0.01 g), desiccator and thermometer (±1 °C).
- Sampling and repeatability: Representative sampling is performed according to ISO 11127-1. Determinations are carried out in duplicate; if results differ by more than 10 % (relative to the higher result), the test is repeated.
- Procedure highlights:
- Dry a sample at (110 ± 5) °C for 1 hour and cool in a desiccator.
- Stabilize pycnometer and water to room temperature (about 1 h), measure water temperature.
- Weigh pycnometer empty, with test portion, with test portion plus water, and with water only; calculate apparent density using these mass differences and water density at the test temperature.
- Expression of results: Report the mean of two valid determinations, rounded to the nearest 100 kg/m3. Include the test temperature and any deviations.
Applications
- Quality control: Verify batch-to-batch consistency of abrasives and detect packing or moisture variations that affect apparent density.
- Process dosing: Accurate apparent density supports consistent volume-to-mass dosing for blasting equipment and helps estimate coverage and consumption rates.
- Procurement and compliance: Provide a standardized, ISO-aligned parameter for supplier specifications and contract acceptance tests.
- Material selection: Assist engineers and coating specifiers in selecting abrasives with the required bulk properties for specific surface-preparation tasks.
Related Standards
- ISO 11127 series (Test methods for non-metallic blast-cleaning abrasives): Part 1 (Sampling), Part 2 (Particle size distribution), Part 4–8 (other test methods).
- ISO 11126 series (Specifications for non-metallic blast-cleaning abrasives): classification and requirements for abrasive types (e.g., slag, garnet, olivine).
- ISO 3696 (Water for analytical laboratory use) for reagent quality.
For laboratory implementation, include the test temperature, test report items specified in Clause 9, and ensure personnel follow the sampling rules of ISO 11127-1. The ISO 11127-3:2020 procedure provides a reliable foundation for abrasive specification, control and comparative testing.
Open preview (PDF)Preparation of steel substrates before application of paints and related products — Test methods for non-metallic blast-cleaning abrasives — Part 3: Determination of apparent density