Overview
ISO 12921:2024 is an International Standard published by the International Organization for Standardization (ISO) that specifies a test method for evaluating the mechanical stability of greases in the presence of water. The standard focuses on measuring the change in consistency - specifically the penetration value - of a grease sample when subjected to working and prolonged working with 10% water content. This method allows manufacturers, laboratories, and users of petroleum products and lubricants to assess how water ingress affects the performance, durability, and mechanical properties of greases.
Key Topics
- Mechanical Stability Testing: ISO 12921:2024 centers on measuring penetration changes in greases after working them both with and without 10% water, simulating real-world conditions where water contamination occurs.
- Penetration Measurement: Penetration testing is performed according to ISO 2137 (2020) both after 60 strokes and 100,000 strokes, providing data on grease behaviour after short-term and prolonged working.
- Water Influence: The standard evaluates the effects of water causing grease softening, hardening, or solubilization, which can lead to loss of lubricating properties or leakage in service conditions.
- Precision and Repeatability: It includes detailed precision data with repeatability (r) and reproducibility (R) metrics, ensuring reliable and consistent test results across laboratories.
- Equipment and Reagents: The procedure details specific equipment such as grease workers and cone penetration devices, and recommends using analytical grade water or synthetic sea water conforming to ISO 3696 and ISO 7120 standards.
- Test Reporting: Standardizes report contents, including product identification, water type used, test results, deviations, and observations for clarity and traceability.
Applications
- Quality Control in Lubricant Manufacturing: Enables manufacturers to verify the robustness and water resistance of greases under mechanical work conditions, ensuring end-product quality and reliability.
- Product Development and Formulation: Assists lubricant developers in formulating greases that maintain their mechanical stability even in wet environments, optimizing performance for applications involving water exposure.
- Maintenance and Reliability Engineering: Helps maintenance professionals select appropriate greases for bearings and other components subject to water contamination, preventing premature failure.
- Lubricant Compliance Testing: Supports compliance with industry norms by providing standardized test results for mechanical stability in the presence of water, which can be referenced in technical datasheets and certifications.
- Research and Comparative Analysis: Facilitates comparative studies between different grease formulations to improve water resistance and evaluate the long-term mechanical behaviour under simulated operating conditions.
Related Standards
- ISO 2137:2020 – Determination of cone penetration of lubricating greases; integral to measuring grease consistency changes.
- ISO 3696 – Specifies quality requirements for water used in analytical laboratory testing, ensuring consistency in water used for the test.
- ISO 7120 – Defines synthetic sea water specifics, applicable as an alternative reagent for water in grease testing.
- ISO 23572 – Covers sampling protocols for lubricating greases to ensure representative testing material.
- ISO 11009 – Establishes methods for determining water washout characteristics of lubricating greases, complementing mechanical stability testing.
- ISO 11007-1 and ISO/TS 11007-2 – Focus on rust-prevention characteristics in greases under wet conditions, related to water interference assessment.
- ASTM D7342 and NF T60-626 – Similar methods assessing grease behaviour during prolonged working with water presence.
By utilizing ISO 12921:2024, professionals in the petroleum products and lubricant sectors can ensure their greases maintain optimal mechanical stability when exposed to moisture, supporting superior performance and longevity of critical lubricated components.
Open preview (PDF)Petroleum products and lubricants — Determination of the mechanical stability of greases in presence of water
