How do Grease Testing work?
Grease is a dispersion of a thickener, such as lithium or calcium soap, polyurea or clay, in base oil with additives. Its behavior is non-Newtonian, so tests measure structure rather than viscosity. Consistency is measured by letting a standard cone sink into the sample for five seconds and reading the penetration depth in tenths of a millimeter, usually after working the grease in a standard worker. Dropping point is the temperature at which the first drop falls from a heated cup, indicating thermal limit of the thickener structure. Oil separation measures how much base oil bleeds through a wire cone under storage conditions. Oxidation tests heat grease in oxygen and record pressure drop, and water washout tests spray or immerse grease to find the percentage lost. Standard cup, cone and temperature geometry give comparable results.
Which Grease Testing variants are available?
- Automatic Grease Cone Penetrometer — An automatic grease cone penetrometer releases a standard cone onto a grease sample for five seconds and measures penetration depth electronically.
- Grease Worker — A grease worker shears a grease sample by forcing a perforated plate up and down in a closed cup, 60 or more strokes at a set rate.
- Grease Dropping Point Apparatus — A dropping point apparatus heats a small cup of grease at a controlled rate and records the temperature at which the first drop falls.
- Grease Oxidation Stability Tester (Oxygen Bomb) — A grease oxidation stability tester heats grease films in a sealed oxygen-filled bomb and records the pressure drop over hundreds of hours.
- Grease Oil Separation Tester (Cone Bleed) — A grease oil separation tester holds a grease sample in a wire-mesh cone at a set temperature and weighs the oil that drains out over 30 hours.
- Grease Water Washout Tester — A grease water washout tester spins a grease-packed bearing in a housing while a jet of water hits it at a set temperature.
How do I choose the right variant?
Choose equipment according to the grease properties in your product specification. Every grease plant needs a penetrometer and grease worker for NLGI grade, plus a dropping point apparatus. Formulators of high-temperature and long-life greases add oxidation stability testing. Storage and bearing-application tests such as oil separation and water washout support quality control and complaint handling. Consider whether the penetrometer needs automatic operation, full-scale or quarter-scale cones, and heating capacity for the dropping point block, which is often 260 to 400 °C for high-temperature greases. Check compatibility with the standard edition cited by customers, and whether consumables such as wire cones, cups and wheel bearings are available. In the RFQ, list methods, sample throughput and the thickener types tested.
Where are Grease Testing used?
Grease Testing are specified in grease batch quality control, NLGI grade determination, high-temperature grease development, bearing grease qualification and storage stability and complaint testing.
Which standards and certifications apply?
Work with Grease Testing is commonly governed by ASTM D217, ISO 2137, ASTM D566, ASTM D2265, IP 396, ASTM D942, ASTM D1264 and ASTM D6184. Instrument certifications such as CE marking are confirmed per configuration and never assumed.
What are the key considerations before purchase?
Grease tests are sensitive to sample handling. Fill cups without air pockets, and bring samples to 25 °C in a bath before penetration testing. Keep cones and worker plates clean and undamaged, and verify penetrometer zero and cone mass and dimensions. Calibrate temperature sensors in dropping point blocks. For oxidation bombs, check pressure transducers and leak tightness, and treat oxygen with care: use clean, oil-free regulators and a ventilated area. Replace consumables such as wire cones and cups per the method. Keep grease waste separate from solvents, and record reference grease checks with certified materials to support laboratory accreditation.
