SECTOR FOCUS: TESTING
Testing the Lubricating Oil Viscosity for Utility Vehicle Engines
Jelena Fischer, Anton Paar GmbH and Andrea Dawidczak, MAN Truck & Bus AG
In a motor vehicle, the term “powertrain” describes the main components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, drive shafts, differentials, and the final drive (drive wheels, continuous track as in military tanks or caterpillar vehicles, etc.). In this context, the term “operating fluids” refers to fluids that comprise products designed to aid the operation of a vehicle, such as engine oil, gearbox oil, transmission fluids, etc. This article focuses in particular on lubricating oils for heavy-duty vehicles.
are based on a rotational measuring principle and have an integrated density measuring cell. The small viscosity measuring cell contains a tube which rotates at a constant speed and is filled with sample fluid. A measuring rotor with a built-in magnet floats freely in the sample. The sample’s shear forces drive the rotor while magnetic effects retard its rotation. Shortly after the measurement starts, the rotor reaches equilibrium speed. This speed is a measure of the fluid‘s viscosity (Fig 1).
Fig 1. SVM™ measuring principle
The most important requirement of a lubricant is to form a film between the moving parts to keep the surfaces separate under all loads and temperatures. The viscosity of the oil can be influenced with additives to have a viscosity that is high enough to form the protective film but low enough not to cause excessive energy losses within the film.
Nowadays, fuel economy is becoming more and more important and the viscosity of the oils is getting lower and lower. It is of great importance that the viscosity remains stable during the whole oil drain interval.
Innovation in Viscosity Determination: SVM™ Stabinger Viscometer™ Series The highly precise viscometers of the SVM™ series
40 LUBE MAGAZINE NO.144 APRIL 2018
As the density cell of SVM™ is integrated, the density measurement does not have to be carried out separately. In fact, one combined measuring cell covers the entire measuring range for viscosity, density, and temperature and is filled in one go. A minimum sample amount of only 1.5 mL is sufficient for multiparameter results in one fast measurement.
Top Benefits for Lubricating Oil Testing Measuring Range In virtually every lab, from time to time a sample outside the “usual” viscosity range needs to be measured. This often poses a problem with traditional measuring methods and is time-consuming to perform. With SVM™ 3001, one combined measuring cell covers the entire measuring range for viscosity,
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
