Overview
EN ISO 1927-2:2012 - Monolithic (unshaped) refractory products - Part 2: Sampling for testing - provides guidance for the representative sampling, reduction and treatment of monolithic refractory materials for inspection and physical testing. The standard applies to all materials formulated as monolithic (unshaped) refractories and is intended to ensure samples reflect batch quality for production control, third‑party certification and acceptance testing.
Key topics and requirements
- Sampling scheme and documentation: requires an agreed, documented sampling plan covering batch definition, packaging, sampling locations, timing, responsible parties and criteria for acceptance.
- Definitions and sample types: clarifies terms such as batch, consignment, unit package, increment, elementary/package/laboratory/test‑piece increments and sample.
- Procurement of batch samples: guidance on selecting unit packages randomly, handling unit packages >35 kg and forming package increments; references ISO 8656‑1 and ISO 5022 for specific schemes.
- Minimum elementary increment masses (examples from standard): dependent on maximum grain size - e.g. 10 mm → 500 g, 3 mm → 200 g, 1 mm → 50 g (adjusted for bulk density).
- Variation classification: use coefficient of variation (C = 100·σ/µ) to classify batch variability (class 1: 0–5%, class 2: 5–15%, class 3: 15–30%) to determine increment numbers; use class 3 when unknown or >30%.
- Size reduction and preparation: describes approved methods for reducing package increments to laboratory increments and preparing test‑piece increments (cast bars, cylinders) while protecting properties to be tested.
- Marking, packaging and storage: requirements to preserve sample integrity and traceability.
- Sampling report: mandatory documentation of sampling details, conditions and chain of custody.
Practical applications and users
- Manufacturers of castables, gunning mixes, ramming mixes, grouts and other monolithic refractories - for factory production control.
- Independent testing laboratories - to ensure representative samples for physical and chemical tests.
- Quality assurance / QC engineers, procurement managers and installers - for acceptance testing of delivered consignments.
- Third‑party certifiers and inspectors - for surveillance sampling and compliance checks.
Related standards
- ISO 1927 series (Parts 1, 3–8) - classification, characterization, test methods and treatment of test pieces.
- ISO 8656‑1 - sampling scheme for raw materials and unshaped products.
- ISO 5022 - sampling and acceptance testing of shaped refractory products.
- ISO 10725 - acceptance sampling plans for bulk materials.
EN ISO 1927-2:2012 is essential for reliable refractory materials sampling, ensuring consistency between production control and acceptance testing and protecting test validity through standardized increment definition, reduction and handling.
