The number of oemspecific viscometrics and performance requirements are growing. Motor oil, or engine oil, is an oil used for lubrica. Understanding the sae motor oil viscosity standard what is motor oil viscosity. This is important, as engine oils naturally thicken as they cool and thin as they are heated. The second number is defined by how an oil flows when at higher temperatures normal engine operating temperatures. The aim of this work is to evaluate changes due to temperature and.
When comparing engine oils for your ride, the most important thing to keep in mind is the oils viscosity rating. This is the basic challenge engineers face when designing engine lubrication. Simply put viscosity is a physical property of a fluid or gas that reflects its tendency to flow. How lubricant viscosity reacts to changes in temperature, pressure or speed determines how well the oil protects your vehicle. The tested materials included mineral engine oils, semisynthetic and synthetic ones that belong to different viscosity classes. But under certain circumstances, they will combine to form an emulsion which looks like coffee with cream, and this will actually increase the kinematic viscosity of oil. Pdf temperature dependent kinematic viscosity of different types. We commonly refer to high viscosity fluids as being thick and low viscosity fluids as being thin.
For instance, an sae 90 gear lube is comparable in viscosity to an sae 50 or sae 40 engine oil. It should be noticed that there is no relationship between the sae engine oil and gear oil classifications. Appendix fapi guidelines for sae viscositygrade engine testing. Although gear oil viscosity is not the same as that of engine oil, it is rated in centistokes. Oil and additive industry value chain integrated petroleum companies additive component suppliers additive companies lubricant companies lubricant sale channels vehicle owners government legislators engine builders industry committees product flow new additives new oil specifications new environmental legislation new hardware requires higher.
Shell mysella s5 n 40 the highest performance natural gas engine oil for use in highly rated sparkignition 4stroke engines requiring low ash oil. These designations apply to oils intended for gasolineengine cars. Oil must reduce friction and wear engine friction and wear are caused by interference contact of moving parts. Water contamination oil and free water dont mix, not chemically anyway. Extensional viscosity can be measured with various rheometers that apply extensional stress.
T he viscosity of an oil changes dependant on the temperature, the pressure, and the actual shear stress on the oil as a result of flowing between moving components. Concern with engine oil quality continues to remain an important topic. Viscosity is an important aspect for oil used in machines and transportation vehicles. Viscosity arising due to internal molecular friction produces the frictional drag effect.
It is rare that an oil will fall into one viscosity range, so centistokes cst are taken into account, which more accurately show oil viscosity. In this paper has been evaluated temperature dependence kinematic viscosity of engine oils in the low temperatures. This measurement is related to how an oil flows when it is cold, such as at engine startup. Sae viscosity grades viscosity table and viscosity chart. Trends in shear stability of automotive engine oils. Pdf excessive additive effect on engine oil viscosity. Dec 17, 2019 the w in the gear oil viscosity grade is for winter grade, like in engine oil viscosity. Whats really important is that you use the oil viscosity your cars owners manual recommends. Look for the viscosity grades recommended by the original equipment manufacturer oem, which you can locate in your owners manual. This page gives an overview of the oil specifications, see also the measurement data of engine oils and gear oils over a wide temperature range.
The type of equipment you use, the engine within, and the temperature outside determines what type of oil to use, how much you need and the cost of the oil. A highperformance natural gas engine oil for leanburn, sparkignition 4stroke engines requiring lowash oil. For this reason the society of automotive engineers sae, in cooperation with engine manufacturers, developed a classification system for motor oils based on viscosity measurements. Viscosity index vi improver has found its largest commercial applications as additives to engine oils. The goal of this paper describes kinematic viscosity and shear stress of two used engine oils, which have been taken from two different passenger cars. A viscometer is used to determine the viscosity of engine oil. Various types of engine oil on the market are created for various purposes. Grade 10w40 from the top half of the chart grade 10w this oil will have a cranking viscosity no greater than 7,000 mpas in a cold engine crankcase even if its temperature should drop to 25 c on a cold winter night and a maximum pumping viscosity of 60,000 mpas. There are two numbers that define the viscosity of an oil. A gear lubricant and an engine oil having the same viscosity will have widely.
Oil viscosity and weight explained with chart to pick the. Demulsibility engine life extension prevents the formation of water in oil emulsion which enters the system through leakage or condensation. Adjusting the oil and oil filters is very important so that the vehicles engine is functioning properly. In this paper has been evaluated temperature dependence kinematic viscosity of engine oils in the. Apparent viscosity is a calculation derived from tests performed on drilling fluid used in oil or gas well development. Selected sae j300 engine oil viscosity classification specifications.
Viscosity of engine oil viscosity table and viscosity chart anton. Viscous fluids help lubricate machines as their internal parts move. What does viscosity mean and how does it affect your engine. The j300 viscosity grades and their requirements are summarized in table 1, while those for j306 are shown in table 2. They consist of mineral, semi or fully synthetic base oil base stocks plus a varying number and amount of additives. Viscosity is defined as how the oil flows as a result of gravity. A complete simulation of engine oil according to its viscosity is done in this study, through the experiment data a mathematical formulas for different engine oils.
Viscosity is resistance to shear or flow in a fluid and a measure of the adhesivecohesive or frictional property. Find viscosity tables and charts for engine oil at multiple temperatures viscosity and density values with their source. The first number ends with the letter w, which stands for winter. Even at this early stage, viscosity was recognized as one of the most important characteristics of an oil. The viscosity of the engine oil will depend on whether the oil is, for example, in the sump, the pump, the cooler, between the cam and followers, or in the crankshaft bearings. In the case of motor vehicle engines, viscous oil helps lubricate engine parts from overheating. Research is focused to commercially distribute automotive engine oil with viscosity. The main goal of this paper is excessive additive for oil filling effect on engine oil dynamic viscosity. The fluids therefore maintain their lubricating power and anticorrosion performance even under these circumstances. Lubrication performance of engine commercial oils with different.
What happens to motor oil as the engine temperature goes up. Therefore the w in an oil viscosity grade is commonly understood to mean that the. While the two numbers specify the sae viscosity grade, the viscosity index shows the temperature related change of viscosity. What is engine oil viscosity firestone complete auto care.
The society of automotive engineers sae publishes the viscosity specifications for automotive engine oils. The viscosity of an oil is measured by its resistance to flow. The insides of a car engine get very hot when the engine is running. Feb 14, 2019 how to pick the right motor oil for your car. Motor oil is used for lubrication of internal combustion engines. There are two related measures of fluid viscosity known as dynamic or absolute and kinematic viscosity. The objective of this project is to measure how the viscosity of motor oil changes with temperature. So a 5w30 will flow easier than a 10w30 at startup temperatures and a 10w30 will flow easier than a 10w40 at normal engine operating temperatures. The w in the gear oil viscosity grade is for winter grade, like in engine oil viscosity.
So what does this all mean to protecting your engine. Low viscosity lubricants are increasingly becoming an important part of the product landscape for the major oems. Engine oils are widely used for lubrication purposes in automobile and related industries. Model codeengine size engine designation fuel type capacity l oil grade oil viscosity column1 engine oil grades and capacities soul 2009 2011 am 1. Pdf lowerature behaviour of the engine oil researchgate. Motor oil, engine oil, or engine lubricant is any of various substances comprising base oils enhanced with various additives, particularly antiwear additive in addition to detergents, dispersants and, for multigrade oils, viscosity index improvers. Viscosity grade the measure of an oils ability to flow at certain temperatures. Examples are power steering fluid, aircraft piston. The lower the viscosity, the less energy it takes to shear the oil and the cooler the oil, but conversely, the lower the viscosity, the thinner the oil film. Volume viscosity can be measured with an acoustic rheometer. Therefore, when considering the physiochemical reasons why polymers alter the viscosity temperature relationships of fluids it is more appropriate to consider the effect of the polymer compared to the viscous beha.
In other words, the oils viscosity has been tested to verify the oils flow under specified low temperatures. Thin, low viscosity oils flow easier to protect engine parts. How polymers behave as viscosity index improvers in. Viscosity is simply the resistance of a fluid to flow. Viscosity of engine oil viscosity table and viscosity. Combustion byproducts and other contaminants carried in the oil also add to. The quality of an engine oil depends on the base stock and its properties as well as on the additives. It is specially developed to provide extended drain oil intervals. Resource conserving or energy conserving these designations apply to oils intended for gasolineengine cars, vans, and light trucks. Viscosity of engine oil viscosity table and viscosity chart. Because it is important to lubricate the engine, it is necessary to start working quickly and low viscosity helps to do it when it is cold. Motor oil lubricates the moving parts, to keep the engine operating smoothly. Understanding the sae motor oil viscosity standard jc motors. Higher viscosity numbers indicate thicker oils because they take longer to flow through the viscometer when tested.
Viscosity has a very important role it effects the heat generation in engine, bearing, brakes and gears,it governs the sealing effect and oil consuption and determines the ease with which the engine can start with varying temperature specially in. Types of motor oil how to pick the right engine oil. If an oil is eligible for sae viscositygrade engine test guidelines for passenger car motor oils or diesel engine oils and the sponsoring. Temperature impacts the flow properties of engine oil. Dynamic or absolute viscosity converting chart dynamic viscosity converting chart with. Follow your vehicle manufacturers recommendations on sae oil viscosity. The main requirements for an engine oil are defined temperature viscosity properties, protection against wear and corrosion, keeping the engine clean, holding particles like soot or abrasives in suspension, yield strength under compression and many more. Lowtemperature behaviour of the engine oil 1765 the sample oil was measured with use of standard spindle of r3 type, which is the most suitable spindle for this kind of test speci. Put simply, viscosity is the most important property of a lubricant. Additionally, 100c reduces the rise of measurement interference for engine oil soot contamination.
If an oil is eligible for sae viscosity grade engine test guidelines for passenger car motor oils or diesel engine oils and the sponsoring company desires to waive testing, the sponsoring company shall conform to the registration process, the acc code, and the multiple test evaluation procedure for the required engine tests. Multigrade oil satisfies the viscosity requirements of one of the w grades at low temperatures and one of the nonw grades at high temperature. Likewise, most engine oils are typically measured at 100c because the sae engine oil classification system sae j300 is referenced to the kinematic viscosity at 100c table 1. The aging of engine oil causes changes to its dynamic viscosity value. Pdf kinematic viscosity and shear stress of used engine oil. Puma motor oil sae 40 meets the requirements of the following. Optimization of different grades engine oil viscosity american. California has now put legislation in place to ban obsolete oils.