Overview
ISO 3187:1989 specifies a laboratory test method for determining creep in compression of refractory products - the isothermal deformation of a refractory material under a constant compressive load. The standard defines the test apparatus, specimen geometry, heating and loading procedures, measurement intervals and data presentation for quantifying creep in compression. It is aligned with related refractories test methods (see Related Standards).
Key topics and technical requirements
- Test specimen: cylindrical sample 50 mm ±0.5 mm diameter × 50 mm ±0.5 mm height with a coaxial hole 12–13 mm diameter; ends flat and parallel; dimensional tolerances specified.
- Loading: total load chosen to produce nominal stresses with ±2% tolerance:
- Dense shaped products: 0.20 N/mm²
- Shaped insulating products: 0.05 N/mm²
- Total load rounded to nearest 1 N
- Test forms:
- Load applied at ambient temperature (furnace switched on), or
- Load applied after reaching and holding the test temperature (pre-soak up to 4 h)
- Heating regime: control thermocouple rise rate 4.5–5.5 K/min (up to 10 K/min to 500 °C permitted); temperature uniformity and stability criteria defined.
- Apparatus: vertical furnace, fixed and moving loading columns, alumina inner and outer tubes, refractory discs, measuring device sensitivity at least 0.005 mm, thermocouples (platinum or platinum/rhodium) per IEC 584.
- Measurements:
- When load applied at ambient: record height and temperature at ≤5 min intervals during heat-up, then at defined intervals during soak.
- When load applied at temperature: record deformation from time of load application at 5 min intervals for the first hour, then 30 min intervals.
- Standard test duration: 25 hours (extensions up to 100 h may be agreed).
- Reporting: corrected plots showing percentage change in height vs. temperature and vs. time, tables of creep at specified intervals, material identification, furnace type, heating rates, load and exposure details.
Applications and users
ISO 3187 is used by:
- Refractory manufacturers and R&D labs assessing creep resistance of bricks, shapes and dense vs. insulating refractories
- Quality control and materials engineering teams for product selection and specification
- Test laboratories validating performance under isothermal compressive load and comparing formulations or sintering conditions
Practical applications include predicting deformation under service loads (e.g., furnace linings, kilns, industrial high-temperature units) and informing design limits for refractory linings.
Related standards
- ISO 1893:1989 - Refractory products - Determination of refractoriness-under-load (rising temperature)
- ISO/R 836 - Vocabulary for the refractories industry
- IEC 584-1 / IEC 584-2 - Thermocouples (reference tables and tolerances)
Keywords: ISO 3187, refractory products, creep in compression, test method, refractoriness-under-load, thermocouple, alumina tube, loading device, isothermal deformation.
