Overview
ISO/TS 11007-2:2023 specifies a laboratory method to determine the rust-prevention characteristics of lubricating greases under a continuous flow of aqueous test fluid (water wash-out). Intended for rolling bearings exposed to flowing water, synthetic sea water or industrial aqueous pollutants, the method assesses a grease’s ability to resist corrosion when corrosion inhibitors may be washed out. This procedure is commonly referred to in industry as the Emcor (emulsion corrosion) test.
Key topics and requirements
- Test principle: Grease is placed in a test bearing and subjected to a programmed sequence of running/stopping while an aqueous test fluid flows through the rig. After ~1 week, bearings are disassembled and outer ring corrosion is rated.
- Test rig & components: Double-row self-aligning bearings (DIN 630 type), adaptor sleeves, V‑ring seals and a specially specified test rig (Annex A).
- Test fluids: Grade 2 water, synthetic sea water (ISO 7120 spec), or 0.5 mol/L NaCl solution (pH 8.0–8.2). Water quality is critical to reproducibility.
- Flow & speed controls: Peristaltic pump flow rate specified at 2.10 ml/min ± 0.2 ml/min; rig speed typically 83 min⁻¹ ± 5 min⁻¹ (≈8.7 rad/s ± 0.5 rad/s) for initial grease distribution.
- Preparation & cleaning: Bearings and plummer blocks are thoroughly cleaned (solvent rinse, propan-2-ol/ammonia mix), checked for residual salts (silver nitrate check) and dried (oven at 90 °C ± 2 °C) before filling with 10.5 ml ± 0.1 ml grease per bearing.
- Safety & precision notes: The specification warns of hazardous solvents and high-temperature washing. The method’s interlaboratory precision has not yet been determined.
Applications and users
- Lubricant manufacturers: Formulation screening and quality control to ensure corrosion inhibitors remain effective under wash‑out conditions.
- Tribology and test laboratories: Standardized evaluation of grease performance for product data sheets and comparative testing.
- End-users in wet industries: Paper mills, rolling mills and other facilities where bearings are exposed to flowing water, emulsions or contaminated aqueous media-used to select greases for rolling bearings prone to seal failure or wash-out.
- Procurement and quality engineers: Specification and acceptance testing for greases intended for wet-service environments.
Related standards
Keywords: ISO/TS 11007-2:2023, rust-prevention characteristics, lubricating greases, water wash-out, Emcor test, corrosion testing, rolling bearings, grease wash-out test, lubricant quality control.
Open preview (PDF)Petroleum products and lubricants — Determination of rust-prevention characteristics of lubricating greases — Part 2: Method with water wash-out