ISO 11009:2021

Overview

ISO 11009:2021 - "Petroleum products and lubricants - Determination of water washout characteristics of lubricating greases" - specifies a laboratory test to evaluate a grease’s resistance to water washout from a ball bearing. The method measures the percentage mass loss of grease when exposed to a controlled water jet at either 38 °C or 79 °C, under defined apparatus and operating conditions. This standard is intended for development and specification purposes; no formal correlation with field performance has been established.

Key topics and technical requirements

• Test principle: A defined mass of grease is packed into a type 6204 deep-groove ball bearing (C3 clearance) in a bronze housing; the bearing is rotated while a water jet impinges on the housing. The grease mass loss after a 60 min ± 5 min exposure gives the water washout percentage.
• Critical test parameters:
  • Rotation speed: 63 rad/s ± 3 rad/s (≈600 min⁻¹ ± 30 min⁻¹)
  • Water flow: 5 ml/s ± 0.5 ml/s through a 1 mm nozzle
  • Nozzle-to-shield distance: 57 mm, impingement 6 mm ± 2 mm above the shield edge
  • Test temperatures: 38 °C or 79 °C
  • Grease charge: 4.00 g ± 0.05 g per bearing; tests performed in duplicate
• Apparatus and materials: bronze housing with spindle/bearings, water heating and flow control, solvent for cleaning (low-sulfur hydrocarbon), and grade 3 laboratory water (ISO 3696).
• Post-test handling and calculation: bearings and shields are dried (typical drying 15 h at 77 °C ± 6 °C, higher for viscous oils) and weighed. Mass-loss is calculated and reported as % (m/m) rounded to the nearest whole percent.
• Visual assessment: standard includes qualitative observations of grease appearance after test (e.g., emulsified, hardened, leaking) and water appearance (clear, milky, supernatant oil).
• Usage notes: the method’s precision is limited; ISO 12924 uses this test as part of the symbol 3 ("water contamination and rust protection") classification with threshold examples (e.g., <10 % and <30 % categories), but caution is advised due to variability.

Applications and users

• Who uses it: grease manufacturers, quality-control and independent test laboratories, R&D teams, bearing and equipment manufacturers, procurement/specification engineers, and standards bodies.
• Practical uses:
  • Developing and comparing greases for water-exposed applications
  • Specifying grease performance for rolling bearings in wet environments
  • Supporting classification in lubricant standards (e.g., ISO 12924, ISO 6743-9)
  • Routine quality control and acceptance testing of lubricating greases

Related standards

• ISO 12924 - Grease specifications and classification (uses washout results for water-contamination symbol)
• ISO 6743-9 - Grease family and condition-of-use designations
• ISO 23572 - Sampling of lubricating greases
• ISO 3696 - Water for analytical laboratory use

Keywords: ISO 11009:2021, water washout, lubricating greases, grease washout test, water contamination, rust protection, ball bearing test, grease specification.