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have a very limited knowledge about those products and they expect assistance from their supplier’s competent personnel who should be armed with the correct information.
Order of UNITI “Lubricant and Mineral Oil ABC”: Beside the standard UNITI design, this booklet can be used as a valuable attractive give-away by using an individual company design for the front and back cover, or by just putting your company imprint or logo on the front cover.
Examples from the Lubricant and Mineral Oil ABC:
SAE Abbreviation for Society of Automotive Engineers Inc., New York, USA. Standards organisation for engineering professionals; publishes technical regulations or standardisations; often associated with SAE-grade viscosity of engine oils and gear oils, as well as in the field of brake fluids.
SAE-Grades Grouping of viscosity grades for engine oils SAE J 300 and gear Oils SAE J 306. Engine oils which meet the viscosity requirements of different grades at high and low temperatures, are classified as multi-grade engine oils. An engine oil with viscosity at -15°C below 3500 mPas and viscosity at 100°C between 12,5 and 16,3 mm²/s, is a SAE 15 W – 40 multi grade engine oil. Gear oils which meet the viscosity requirements of different grades at high and low temperatures, are classified as multi grade gear oils. A gear oil with viscosity at -40°C below 150.000 mPas and viscosity at + 100°C between 13,5 und 24 mm²/s is a SAE 75 W – 90 multi grade gear oil. With the latest revision of SAE J 306 new SAE grades SAE 110 and SAE 190 for automotive gear oils were introduced.
Viscosity Measure of the flow properties of a liquid or gas. Characterises the internal friction of a fluid. High viscosity means low fluidity and low viscosity high fluidity. Viscosity is related to the molecular structure of the fluid components. To overcome the resistance between the molecules due to the attractive forces, a certain force is required. Given the relation between the required force and induced velocity gradient, the dynamic viscosity is defined as a constant of proportionality.
40 LUBE MAGAZINE NO.145 JUNE 2018
Dynamic viscosity ɳ = shear stress τ / shear rate. The dynamic viscosity is measured in Pascal second (1 Pas = 1 Ns/m²).
1 m Pas = 10–3 Pas = 1 cP. Kinematic viscosity ν = ɳ/ᵨ The kinematic viscosity is measured in m²/s or mm²/s. 1 mm²/s = 10–6 m²/s = 1 cSt.
Under the influence of gravity the kinematic viscosity is the ratio of dynamic viscosity and density (i.e. in case of the free outflow of the fluid, measurement is determined by means of the capillary viscometer). An increase in temperature leads to a decrease of the inner friction of fluids and gases. Due to the viscosity/temperature dependency, the reference temperature must be quoted, e. g. 30mm²/s/40 °C, 68cSt/50 °C.
Noack-Test The Noack-Test determines the evaporating losses of lubrication oils at high temperatures (testing temperature: 250°C). The evaporating loss of oils, determined according CEC L-040-93, depends on the base oil and is impacting the oil consumption. The Noack value is an important parameter for engine oils and therefore part of many specifications.
EMAIL LINK
kubatzki@uniti.de
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