BS EN ISO 11127 — Test Methods for Non-Metallic Blast-Cleaning Abrasives Standard Series

🛠️ BS EN ISO 11127 is the UK adoption by BSI of the ISO 11127 series covering test methods for non-metallic blast-cleaning abrasives (2011 edition, superseding the 1998 edition). It specifies sampling and physical-property test methods for non-metallic abrasives (e.g. garnet, copper slag, nickel slag, quartz sand) used for blast cleaning of steel surfaces, including particle size distribution, apparent density, hardness, defective particles and microstructure, foreign matter and moisture. It is the basis for quality control and acceptance of mineral abrasives. The series comprises seven parts, prepared by the UK technical committee STI/21 (steel surface preparation).

Some parts of this series were sourced from scanned documents; the technical content is compiled from publicly available domain knowledge and the authoritative text remains the official BSI publication.

1. Scope and Overall Framework 📌

BS EN ISO 11127 applies to non-metallic abrasives used for blast cleaning of steel surfaces before application of paints and related products. It is used together with ISO 8504 (surface preparation methods) and ISO 11125 (test methods for metallic abrasives): 11125 covers metallic abrasives, while 11127 covers non-metallic abrasives, together covering the two major classes of blast-cleaning abrasives. The test methods serve both manufacturers’ factory inspection and users’ incoming acceptance and field process control.

The series is organised as “sampling (Part 1) + individual property tests (Parts 2-7)”, corresponding in structure to the metallic abrasive series, but with differences in sampling division, sieve analysis and density measurement due to the characteristics of non-metallic abrasives (brittle, porous, from mineral or industrial by-products).

2. Series Structure and Technical Highlights 🔧

The table below lists the subject and scope of each part.

3. Key Technical Requirements ⚙️

• Sampling: Number of sampling units, sample quantity and dividing method from a batch (bags, boxes, barrels, bulk bags), ensuring sample representativeness.
• Particle size distribution: Mass percentage on each sieve using standard sieve combinations, plotting the particle-size curve and assessing coarseness and grading.
• Apparent density: Mass per unit volume using a specified container and tapping procedure, an important parameter for consumption and dosing control.
• Hardness: Micro-hardness test conditions and number of determinations, assessing fragmentation rate and cleaning ability.
• Defective particles and microstructure: Metallographic or microscopic evaluation of particle shape, porosity, cracks and inclusions, judging internal quality and brittleness.
• Foreign matter and moisture: Soluble salts, foreign inclusions and moisture content, preventing substrate contamination and protecting coating adhesion.

4. Engineering Practice and Application 🛠️

In coating projects for large steel structures such as ships, bridges, tanks and petrochemical plants, the 11127 series is the core basis for non-metallic abrasive quality control. Suppliers provide abrasive test reports per the series methods. Coating contractors test each batch for particle size, density, hardness, foreign matter and moisture to ensure that cleanliness grades such as Sa 2.5 and the specified roughness are achieved. Process engineers combine abrasive particle size and blasting pressure to control surface roughness, providing an ideal substrate for coating adhesion.

Contamination by soluble salts (e.g. chlorides) is an important cause of early coating failure; combining the foreign-matter test (Part 6) with surface salt detection effectively avoids coating blistering and disbonding caused by soluble salts carried by the abrasive.

5. FAQ ❓