BS EN ISO 11126 — Non-metallic Blast-Cleaning Abrasives for Preparation of Steel Substrates

🛠️ The BS EN ISO 11126 series is the British Standard implementation of EN ISO 11126, which is identical to ISO 11126. It specifies non-metallic blast-cleaning abrasives used for removing rust and old coatings and for producing a suitable profile (anchor pattern) on steel before painting. The series defines classification, technical requirements, test methods and designation for various non-metallic abrasives (copper refinery slag, coal furnace slag, nickel refinery slag, iron furnace slag, fused aluminium oxide, olivine sand and so on), superseding the earlier BS 7079-F series.

1. Series Overview 📌

The master document is Part 1, giving classification, designation and general requirements; the remaining parts (Parts 3 to 10) specify the technical requirements of each abrasive (copper refinery slag, coal furnace slag, nickel refinery slag, iron furnace slag, fused aluminium oxide, olivine sand and so on). The UK committee is STI/21 (Surface preparation of steel), mirroring ISO/TC 35 SC12 and CEN/TC 139.

2. Series Structure and Technical Points 🧩

The series contains 9 standard documents, as shown below.

BS EN ISO 11126-1:1997 is identical to ISO 11126-1:1993 (including two technical corrigenda of 1997). The series replaces the BS 7079-F series (F1 general, F3 copper slag, F4 coal slag, F5 nickel slag, F6 iron slag, F7 fused aluminium oxide, F8 olivine sand), with ICS 87.020.

3. Key Technical Requirements 🔧

3.1 Classification and designation (Part 1)

Part 1 classifies abrasives into metallic and non-metallic groups (this series covers non-metallic) and defines the initial particle shape (angular, spherical, mixed) and designation rules.

3.2 Abrasive specifications

The individual parts specify particle size distribution, hardness (for example Mohs or Vickers hardness), apparent density and chemical composition (for example free silica content, water-soluble salt content), ensuring the abrasive does not contaminate the treated surface.

3.3 Designation and inspection

The standard requires the abrasive packaging to be marked with the standard number, abrasive type and grade, and specifies sampling and test methods to verify particle distribution, moisture and impurities.

4. Practical Engineering Application 🛠️

• 🔍 Abrasive selection: choose the appropriate particle size and hardness according to the required cleaning grade, target profile and environment.
• 🔧 Application control: control blast pressure, distance and angle to ensure uniform cleanliness and anchor pattern.
• 📊 Inspection and acceptance: inspect abrasive particle distribution, moisture and chemical composition on receipt.
• 📋 Environment and recovery: recover and reuse abrasives, and treat dust and waste to protect the working environment.

4.1 Implementation tips and pitfalls

On-site management of blast-cleaning abrasives is an important part of coating quality control. First, incoming inspection is not optional: sample-test particle size distribution, moisture, apparent density and chemical composition per the standard, rejecting abrasives that are caked, damp or contaminated with oil or salts. Second, recycled abrasives gradually break down, powder and accumulate contaminants, so determine the replacement cycle by the standard or site trials to prevent fine debris and soluble salts remaining on the surface. In addition, environmental conditions (relative humidity, dew point, steel temperature) directly affect the cleaning quality; work under the conditions required by the standard and control blast pressure, distance and angle to obtain a uniform anchor pattern.

For severe corrosive environments such as marine and chemical service, prefer abrasives with low salt and low free silica, and apply the first primer coat promptly after blasting to prevent flash rusting. Abrasive recovery and dust collection systems should be in place, both to protect operators and to reduce environmental pollution.

5. Frequently Asked Questions ❓