Overview
EN ISO 8895:2006 (identical to ISO 8895:2004) defines a standardized laboratory method for determining the cold crushing strength (CCS) of shaped insulating refractory products at ambient temperature. The standard specifies sampling references, test-piece preparation, required apparatus, test procedure (compression test), calculation and reporting of results. It is intended for manufacturers, test laboratories and specifiers of insulating refractories.
Key topics and technical requirements
- Scope and sampling: Applies to shaped insulating refractory products; sampling and acceptance testing follow ISO 5022 (referenced).
- Test principle: A prepared test piece is compressed at room temperature in a mechanical or hydraulic crushing-strength machine until collapse or until its height is reduced to a specified fraction of the original. The maximum load is used to calculate CCS.
- Apparatus and measurement:
- Compression machine with progressively controllable load, spherical seating platen and ground platens for good alignment.
- Instruments to record force (to known accuracy), a micrometer or deformation gauge to measure compression, and measuring equipment to verify test-piece geometry.
- Drying oven (controlled at 110 °C ± 5 °C) for conditioning specimens.
- Test pieces: Nominal half‑brick sizes are specified; example dimensions given in the standard include 114 × 114 × 76 mm and 114 × 114 × 64 mm (or other mutually agreed sizes for special shapes). Faces must meet strict flatness and alignment checks.
- Loading rate: