Overview
ISO 22286:2018 specifies a standardized laboratory method for the determination of the dropping point of lubricating grease using an automatic apparatus. The dropping point is the temperature at which grease passes from a semi‑solid to a fluid state under defined test conditions. This standard is intended for quality control, product classification and specification tasks within the petroleum products and lubricants sector.
Key topics and requirements
- Scope and sampling: Applies to lubricating greases; sample collection follows ASTM D 4057 unless otherwise specified.
- Principle: A grease‑filled cup is heated in a measuring cell. When a drop of grease flows through a calibrated orifice the temperature is recorded by a photoelectrical detector.
- Apparatus essentials:
- Grease cups and cup plug gauge with dimensions given in Annex A.
- Calibrated rods for orifice verification (2.78 mm and 2.82 mm referenced).
- Measuring cell with heating capability 0 °C to 300 °C, precision 0.5 °C, photoelectrical detector and cooling device.
- Control unit able to control heating rates between 1 °C/min and 10 °C/min and display temperature to 0.1 °C.
- Test procedure:
- Cup selection and orifice verification; reaming or discarding cups outside tolerances.
- Standardized filling technique to avoid air bubbles and occluded orifices.
- Heating schedule: use 10 °C/min until ~20 °C below expected drop point, then 1 °C/min until detection (alternative: continuous 10 °C/min for unknown samples).
- Automatic stop and display when the photoelectrical cell detects a drop (safety stop at 300 °C if no drop).
- Result expression and reporting:
- Report dropping point in °C rounded to nearest degree.
- Test report must reference ISO 22286:2018, identify product, list test conditions (starting temperature, heating rate), report the result and date.
- Precision: Repeatability and reproducibility are defined and calculated per ISO 4259‑1; specific statistical formulas are provided in the standard.
Applications and users
- Industries: lubricant and grease manufacturers, petrochemical labs, OEMs, third‑party testing laboratories.
- Use cases:
- Quality control and production acceptance testing of grease batches.
- Product specification and classification (particularly for soap‑based greases).
- Research and development when comparing grease formulations or thickeners.
- Note: The dropping point is an indicative property and does not directly define service temperature limits.
Related standards
- ISO 2176 - Dropping point determination (manual method)
- ISO 6299 - Dropping point (wide temperature range)
- ISO 4259‑1 - Precision of measurement methods and results
Keywords: ISO 22286:2018, dropping point, lubricating grease, automatic apparatus, grease testing, petroleum products and lubricants, grease quality control.