Continued from page 17
Besides delivering a 5-digit density value at an individual temperature between 15°C to 100°C, it is used to optimise the measured precision of the kinematic viscosity. This possibility arises from the fact that current measurements lead to an overdetermined parameter set that can be used for this optimisation.
The techniques described above can be categorised as representative examples of precise and automated viscometers. All principles lead to specific pros and cons.
The new kinematic viscometer ERAVISC X, is the first device on the market based on this novel differential pressure capillary method.
Typical requirements by professionals are highest measurement precision, but also flexibility when it comes to measurement temperature and suitability for different products. The following table summarises the most important properties in a simplified manner:
is clearly given with a maximum statistical difference of 1.2 %, whereas the average absolute difference is only 0.4 %. If you compare these figures with typical reproducibility according to current standards, there is certainly positive confirmation.
Conclusion
In the field of lubricant viscometry there are various measurement technologies available. Most of them deliver highly precise results but are inflexible when it comes to measurements at changing measurement temperatures. The ERAVISC X viscometer uses a new technical approach, the “differential pressure capillary method”, to combine the advantages of established methods for direct and highly accurate measurement of kinematic viscosity. Laboratories now have a modern alternative for flexible viscosity and density analysis for base oils and lubricants.
eralytics.com
Comparison study shows excellent correlation When new measurement methods are offered, questions understandably arise regarding measurement precision and comparability with existing methods. For this reason, a comparability study was carried out together with an independent research institute and an industry partner. In this study a total of 42 representative oil samples were compared. There was a mix of gear oils, engine oils and hydraulic fluids both mineral oil and ester based with a maximum kinematic viscosity at 40°C up to 500 mm²/s. The sample matrix was built up of fresh oil samples, in-service oils and artificially aged oil samples.
The following chart shows the correlation between kinematic viscosities at 40°C measured with the ERAVISC X versus results measured according to ASTM D7042. The comparability of the measurement results
LUBE MAGAZINE NO.181 JUNE 2024 19
Thomas Feischl, based in Graz, Styria, AT, is currently a Director of Business Development at eralytics GmbH. Thomas Feischl holds a Master of Engineering in Geoscience - Applied Geophysics from Montan University Leoben. With a robust skill set that includes Key Account Management, Technical Product Marketing, Product Management, Sales Management, Project Management and more.
Thomas’ current focus is on measurement technology for oil condition monitoring in combination with promising software solutions.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68
